Torque - Science topic

A 10 X 10 three-story precast building with a floor area of 100 m2 with 30 cm thick concrete walls in a large earthquake with an acceleration of 1.5g has some overturning moment tendency.

Wanted 1. how much does the precast weigh

2.the inertia and shear base created at the 1.5g acceleration

3. plus the magnitude of the overturning moment of the entire building.

The building weighs 340 tons

Payload is 80kg/m2 = 24 tons

The floors another 24 tons

The building finally weighs 340+24+24= 388 tons without the base.

Inertia and base intercept = mass X acceleration = 388 ton X 1.5g = 582 tons

Overturning moment = height X inertia = the first floor is 3 m high the second 6 and the third 9 total 3+6+9 = 18m

Each of the three floors has an inertia of 582/3 = 194 tons

18mX194ton = 3492 ton overturning moment

But the precast as a rigid structure has a double lever arm, that of the height and that of the width.

So we divide the torque of 3492 tons by the width of the building which is 10 meters 3492/10 = 349 tons.

Every single anchor I have can withstand 100 tons of torque at two meters depth.

If we place 8 anchors around the perimeter, we will not have any loss of support from the ground due to the total withdrawal of the area of the base of the building, so no damage in the earthquake of 1.5g acceleration.

A 300 sq.m pre-fab house costs 310,000 euros finished today + 30,000 the eight anchors = 340,000 euros and you have the most earthquake-proof house in the world.

A conventional house today costs 2,000 euros per sq.m when finished, 300 sq.m costs 600,000 euros.

Choose.

https://www.youtube.com/watch?v=XsHC9WJwgyU

My proposal for anti-seismic constructions is to prestress the sides of the reinforced concrete walls as well as to compact them with the foundation soil at the same time.

Prestressing + compaction on the sides of the walls Prestressing (generally compression) on the sidewalls has very positive effects, as it improves the oblique tensile trajectories. On the other hand you also have the other good thing... the non-shear failure of the cover concrete due to the high tensile strength of the steel, the reduced cracking and the increase in the elastic and dynamic displacement area due to compression, which increases the effective cross-section and stiffness of the structure, and most importantly increases the response of the cross-section to the intersecting base. If prestressing is combined with compaction in the soil then we divert the seismic loads into the soil, prevent the moments at the nodes, control the eigenperiod and ensure soil samples and a strong foundation.

I am looking to design and further running simulations and analyse a low speed shaft of a typical wind turbine. What should be the optimal shaft diameter and length for a given torque and rotational speed requirement in a transmission system of a wind turbine. Do you recommend any good software to run FEA simulations for validation analysis purposes.

Any suggestion, I will much appreciate.

I am looking to design and further running simulations and analyse a low speed shaft of a typical wind turbine. In particular I am looking to design the shaft diameter and length and any other connection components such bearings, keys and so on, for a given torque and rotational speed requirement in a transmission system of a wind turbine. Do you recommend any good software to run FEA simulations for validation analysis purposes.

Any suggestions or comments, I will much appreciate.

I am looking to design and further running simulations and analyse a low speed shaft of a typical wind turbine. In particular I am looking to design the shaft diameter and length and any other connection components such bearings, keys and so on, for a given torque and rotational speed requirement in a transmission system of a wind turbine. Do you recommend any good software to run FEA simulations for validation analysis purposes.

Any suggestions or comments, I will much appreciate.

Interpreting the FMR data for SOT

I want to prepare data sets to train neural network to estimate 3 phase induction motor speed. I am using Denfoss make FC-302 AC drive to run 3 HP IM at different speed. I can export rms value of AC drive terminal voltage and phase current ,power,torque. etc to excel sheet.

From excel data (RMS voltage and current) i can implement abc-Alpha beta transformation in simulink. This alpha beta componentes of voltage and current can be used to obtain rotor flux . But i am feeling i am missing the phase relation when recording RMS voltages and currents.This may result in incorrect rotor flux value.

And also i am unable find Induction motor resistance ,mutual inductance and leakage inductance value in technical specification provided by the manufacturers.

What are the methods for estimating the engine torque other than the above

I was trying to solve a single particle sedientation problem where the particle rotates and the magnitude of the angular velocity is significant. I have correctly solved the linear velocity calculation from the force. However I am having trouble calculating the angular velocity from the calculated torque. I am sure that the torque calculation is correct because I have solved a different problem to assure that. Also the linear force and updating the linear velocity from the force is also correct, as I have solved various problems to ake it sure. But I am having trouble in calculating the angular velocity from the calculated torque. Can anyone help me? refer me some papers please? thanks in advance

Hello. I am working on a project that investigates the stresses in severe scoliosis. Unfortunately, severe scoliosis has not been studied much using FEM. Can you help me to find the suitable Loading and Torque for the situation when the cobb angle is greater than 40 degrees? Or to Recommend me an article that has good information in this field.

Thank you so much for your attention and participation.

Based on the acoustic-elastic effect, the ultrasonic method can measure the axial force of the bolt. Can it measure the torque of the bolt?

There is so much confusing content about torque calculations of single screw extruder system. I am unable to figure out which is right or wrong. I need a little bit help regarding torque calculations for single screw extruder system for PLA.

Has anyone known papers on torque estimation control using motors without torque sensors, or related to robot applications? thank you!

Currently, I am using the motor without torque sensors to control the torque output at the joint of the robot, and I have achieved good results. However, I am distressed that there is no theory to support further and improve my idea. I was frustrated in searching for papers. I would like to ask, does anyone know of a similar article using motors without torque sensors for torque control?

I need to know the motor torque that can provide me a clamp force of 98N using a cable pulley mechanism as shown below in the figure. Any suggestion on how should I should approach to tackle this problem?

Regards,

Sameed.

Hello. Does anyone know why the torque of bipale wind turbine optimized with the gradient method doesn't start from zero. Thank you for your answers.

There are different frictions in the ball valve aganist openning torque which are packing friction, seat friction and unballanced forces. I am looking for a sample of torque calculations for a ball valve showing the amount of torque for overcoming these frictions.

Hello, I'm a beginner at matlab/simulink and EV.

Recently, I studied EV fuel efficiency simulation using matlab and simulink, but there is something I don't understand. The MCT method (measured by dividing into UDDS, HWFET, and constant-speed sections) was used to measure fuel efficiency, and simulation output data (Time, Distance, Battery SOC, motor RPM, motor Torque, SOC voltage, Electric consumption current, Electric power) were obtained.

Based on these data, I would like to calculate the total amount of battery discharge energy and charge energy for this vehicle. When measured using an actual car rather than a simulation, the discharge energy amount was 37kWh and the charge amount was 42kWh. The actual battery specifications were 120Ah, 319.4V. I used a machine for actual measurement, but I wonder which data I should use to calculate the simulation using the output data above. And I also want to know how to calculate it.

I've actually tried it

1. integrate Electric power

2. To multiply the motor current and SOC voltage and integrate the results

But I can't judge whether these two methods are correct or not. I need your help. Thank you.

This is a boundary control problem of a hybrid ODE-PDE system. The system consists of an actuator, a flexible link fixed to the actuator, and a tip mass at the free end of the link. In most literature, two control inputs are used for the simultaneous position and vibration control of the said system: One is the actuator's torque and the other is a force at the tip mass. The application of a control force at the tip mass of a manipulator does not seem to be a practical solution. Can we use only the actuator's torque to simultaneously control the position and vibration of the beam and the tip mass?

I would be grateful to anyone for sharing any theorem or paper addressing this issue (in support or against).

Thank you!

Hello everyone

Is the maximum torque per ampere (MPTA) method only applicable in case of synchronous motors or can it be used in the control of generators?

Hello,

I've successfully simulated the closure of a flapper non-return valve as illustrated.

The inlet velocity increases gradually with a specific acceleration.

The following UDF is used to specify the motion of the flapper:

#include "udf.h"

DEFINE_SDOF_PROPERTIES(flappers_motion, sdof_prop, dt, time, dtime)

{

Six_DOF_Object *sdof_obj = NULL;

sdof_prop[SDOF_MASS] = 2.73e-3; /* flapper's submerged weight */

sdof_prop[SDOF_IXX] = 2161.86e-9; /* around the hinge */

sdof_prop[SDOF_IYY] = 367.96e-9;

sdof_prop[SDOF_IZZ] = 2471.27e-9;

real m= sdof_prop[SDOF_MASS];

real L= 0.024479 ;

sdof_prop[SDOF_LOAD_M_X] = 0 ;

sdof_prop[SDOF_LOAD_M_Y] = 0.0;

sdof_prop[SDOF_LOAD_M_Z] = 0.0;

real th_deg = theta * 180 * 7 / 22 ; /* valve opening angle, in degree */

sdof_obj = Get_SDOF_Object(DT_PU_NAME(dt));

if (NULLP(sdof_obj))

{

/* Allocate_SDOF_Object must be called with the same name as the udf */

sdof_obj = Allocate_SDOF_Object(DT_PU_NAME(dt));

SDOFO_1DOF_R_P(sdof_obj) = TRUE; /*1DOF rotation*/

SDOFO_DIR(sdof_obj)[0] = 1.0;

SDOFO_DIR(sdof_obj)[1] = 0.0;

SDOFO_DIR(sdof_obj)[2] = 0.0;

SDOFO_CENTER_ROT(sdof_obj)[0] = 0.0;

SDOFO_CENTER_ROT(sdof_obj)[1] = 0.0;

SDOFO_CENTER_ROT(sdof_obj)[2] = 0.0;

SDOFO_CONS_P(sdof_obj) = TRUE; /* constrained motion */

if (SDOFO_CONS_P(sdof_obj))

{

SDOFO_LOC(sdof_obj) = 0.0;

SDOFO_MIN(sdof_obj) = -0.0349 ; /* min allowable angle */

SDOFO_MAX(sdof_obj) = 1.0471 ; /* max allowable angle */

SDOFO_INIT(sdof_obj) = SDOFO_LOC(sdof_obj);

SDOFO_LOC_N(sdof_obj) = SDOFO_LOC(sdof_obj);

}

}

}

But now I want to simulate the closure of the flapper, taking into account the friction at the flapper's hinge.

I tried to just assign the friction value to "sdof_prop[SDOF_LOAD_M_X]" ,but the flapper started to move backwards (opening) until the flow increases, which is not correct.

So I want to get the value of the hydrodynamic torque of the flapper, and compare it to the friction with some kind of "if statement" that may look like this:

real static_friction= 50;

real kinetic_friction=40;

real hydraulic_torque =??? ;

If (hydraulic_torque<static_friction)

{

sdof_prop[SDOF_LOAD_M_X]=0

}

else

{

sdof_prop[SDOF_LOAD_M_X]=-1*kinetic_friction;

}

BUT THE PROBLEM IS :

I don't know the udf code that can get the actual value of the hydraulic_torque on the flapper to compare it to the friction value.

Your help is highly appreciated.

Thanks a lot in advance.

Hello,

I am hoping that someone who is well versed in statistics can help me with my analysis and design. I am investigating the torque produced via stimulation from different quadriceps muscles. I have two groups (INJ & CON), three muscles (VM, RF, VL), three timepoints (Pre, Post, 48H) in which torque is measured at two different frequencies (20 & 80 Hz). In addition to the torque, we also want to look at the relative change from baseline for immediately Post and 48H in order to remove some of the baseline variability between muscles or subjects. A ratio of 1.0 indicates same torque values post and Pre. This is a complex design so I have a few questions.

If I wanted to use repeated measures ANOVA, I have to first for normality. When I run the normality test on the raw data in SPSS, I have one condition that fails and others that are close (p < 0.1). When I run the ratios I also have a condition that fails normality. Does this mean now that I have to do a non-parametric test for each? If so, which one? I am having a difficult time finding a non-parametric test that can account for all my independent variables. Friedman's is repeated measures but it is not going to be able to account for group/frequency/muscle differences like an ANOVA would.

Is repeated measures ANOVA robust enough to account for this? If so, should I set this up as a four-way repeated measures ANOVA? It seems like I am really increasing my risk of type I error. It could be separated it by frequency (20 and 80 Hz) because it's established a higher frequency produces higher torque but as you can tell I have a lot of uncertainties in the design. I apologize if I am leaving out vital information in order to get answers. Please let me know and I can elaborate further.

Thank you,

Chris

Hi there,

I am looking at the technical reasons why torque control is better then position control for biped, quadruped...

If the research gate community can provide insights I iwll greatly appreciate

thank you very much

The individual foundations of the structures have been completely removed

The walls must be connected with foot girders which, mainly, try to receive the overturning torque.

That is, we do not rely on individual foundations to receive torque.

Much more ... when there are multi-storey constructions, there are always the corresponding floors of the Underground, which "anchor" the reinforcement of the wall.

It has been proven that buildings with Underground floors are much stronger in the earthquake because there is better anchoring of the superstructure reinforcement inside the basement walls, and because the walls of the Underground floors are strong in torques.

Foot girders in large earthquakes, try unsuccessfully to pick up these huge torques that lower the walls of smaller buildings, and are usually unable to pick them up.

But as much as it seems that the anchoring of the wall reinforcement inside the Underground floors is the same with my own design proposal, they are different.

I do not suggest just a simple anchoring to the ground.

I suggest compression on the sides of the walls combined with anchoring in the ground.

Where are the differences between the anchoring inside the walls of the Underground floors, and the pre-tensioning + anchoring to the ground.

1) We insulate the Underground floors externally, then we rub them around the perimeter.

Due to the looseness of the rubble, their reaction to the torque of the whole structure is small.

But they resist with their own weight and this is a positive reaction to the moments.

If the Underground floors have the same mass as the mass of the upper structure, then yes we have anchoring.

But this is not possible.

Usually the floors are much more than the Underground floors and this means that the Underground floors in large earthquakes have a tendency to overturn, but small.

Beware .. I'm not talking about a complete overturning of the building, but a small overturn of the total area of ​​the base of the Underground floors.

This means that the building loses some ground support.

This is equivalent to creating a corresponding torque from the unsupported static loads, which contrasts with the torque of the building.

These two opposing torques create cross-sectional failures.

This does not happen with the full anchor with my mechanism

2) The prestressing that I propose on the sides of the walls ensures less deformation by bending, zeroes the tensile strength in the cross section, at which point the shear failure of the coating concrete due to the high tensile strength of the steel and its low tensile strength. It ensures that after leaks the construction will return to its original position, so the pre-tension is considered elastic functionality.

It also provides resistance to the shear of the base. Anchoring + prestressing ensures the neutralization of moments (M), upright forces (N) (compressive and tensile), and shear (Q) and deflects inertia tensions into the ground by preventing displacements that deform and break cross-sections around them. nodes.

Preliminary simulation and numerical investigation was carried out at the National Technical University of Athens in order to draw useful conclusions regarding the usefulness of the new seismic technology. The results were encouraging, as it significantly increased the load-bearing capacity and the shear strength of the cross section near the base by 31%, although the simulation was not performed correctly, resulting in insufficient calculation of the actual benefits. The method applies compression to the cross-section of the wall or shaft using tensioned tendons on all their sides, which are firmly anchored to the ground with expanding pile and anchor mechanisms. The method of compressing the sides of the cross-sections and the mechanism of the anchoring have the following purpose. The prestressing plus the anchoring of the wall sides from their highest level with the foundation ground ensures slight deformation and eliminates the right forces (N), torques (M) and shear (Q). It deflects the inertia intensities in the ground, increases the active cross-section of the wall, ensures a strong foundation ground, corrects the oblique tensile arrows, restores the construction to its original position even after inelastic leakage. Provides less ground displacement, at which point less acceleration. What they did not do in the attachment simulation and the results were altered are the following.

1) The title of the simulation states that it will be placed in a bearing of the carrier while in the simulation it was placed in all 9 pillars of the three-storey construction. The method is effective when you place on all sides of the wells or in elongated walls due to the double lever they have, that of the height and width which helps to reduce the moments of overturning of the walls.

2) In the simulation the anchoring to the ground was not applied because what they did was to apply only loads to the nodes of the highest level. This increases the stiffness of the columns as well as increases the strength of the cross-sections towards the intersection of the base, but it does not deflect the forces in the ground, since there is no anchoring, with the result that the torques inevitably lead to the cross-sections of the joints and break them.

3) The walls, because they are anchored from all their sides to the ground, have more anchoring mechanisms than the columns, which have a small square cross-section and accept only one tendon in the center of their cross-section, so they do not have the required performance in simulation, due to the reduced number of anchorages. On the other hand the walls are more rigid by nature so the deformation is less than with the columns. Also the resistance of the walls to the shear force of the base is by nature greater than that of the small cross section of the column. All of these coefficients that are absent from the simulation distort the results. Another serious comparison factor between my method and the trampled method which was ignored in the simulation, is the high tensile strength of the steel and the low shear strength of the concrete which contribute to the premature rupture of the concrete overlap and the , which destroys the cooperation of concrete and steel in the mechanism of relevance. In the pre-tensioning of my method there is no relevance so neither is this problem. Of course, the increase in the capacity of the foundation soil was completely ignored.

My research is multidimensional. It consists of three different fields of research. For this reason you need a lot of money, time, knowledge of science and above all a lot of patience. Nobody finances my research because they can not assess the risk of investing without having this knowledge that I have gained from my 14 years of research and of course they must be rich. Many times money and knowledge do not go together, although in research it is a necessary condition to have both in order to have results. Conduct.. 1) Research on the response of the structure to seismic shifts with and without my method. 2) I investigate..The response of the foundation ground to static and seismic loads, with and without the anchoring mechanism. 3) I investigate The design of the appropriate anchoring mechanism so that it can withstand the calculated traction loads, and has the ability to improve by compacting different quality soils They are three different researches ... (Civil engineering research, Geological engineering research, Mechanical engineering research) ... with one purpose. To make the constructions in the earthquake cheaper and stronger.

Created a single stage speed reducer in Adams view. Applied a constant torque on input gear. After simulation, plotted the torque vs time for output shaft. But torque curve is fluctuating not a constant one. As per theory the output torque must be gear ratio times the input torque. I'm not getting it in adams view

What is the best speed/torque from quality/price point of view?

We are going to establish a new test rig for motors with power up to 500 W.

I have seen that almost all four-wheeler commercial vehicles or power requirements over 10 kW, PMSM or Induction motors are used. Is the reason behind this is more torque ripple and lower speed range of BLDC motors? What are the other reasons?

But if I want to use a BLDC motor for a power requirement of around 40 kW in an EV, considering better power density, what are the disadvantages that can be faced. What are the other advantages of BLDC that can support its application in this case?

Is there any commercial EV that is using a BLDC motor for the power requirement range of 30-50 kW?

Hi ,

I have transient CFD of a rotating Vertical Axis Wind Turbine. The torque changes with the rotation angle theta, I wish to obtain a plot of torque against azimuth angle as attached below and other properties as well. I am currently unsure how to do this as I can only do a standard XY plot on Ansys.

I got my viscosity study data which includes shear stress, shear rate, viscosity, and torque and now I want to find out how to calculate shear train, storage modulus, and loss modulus from these data?

I am doing a project on power generation using multiple humps. Force is known. All the respective gear and shaft radii are known. y using this, this I can found torque using the relation T=F*l ...

I have a relation P=2 pi NT.. but in this relation power and rpm are unknown...

Is there anyway to find the power or rpm? Any other formula to find power with respect to rpm if available then please share.

Thanks

while observing graph between flow coefficient and torque coefficient why torque coefficient suddenly drops?

Considering a four wheel skid steering heavy robot of one ton, I need to know the minimum torque needed to rotate itself from standstill.

Are the calculous very easy or there is a paper that is exhaustively focused on this issue?

In my opinion, the wheels torque should be greater than (i.e. win) the static friction considering that all four wheels are not rotating. Indeed the robot should move normal to its longitudinal axe which in our case coincides with the longitudinal axes of the wheels.

Other than the impact of an agricultural environment on the static friction, what is the impact of the wheel orientation?

What is the impact of the center of gravity in case it does not coincide with the center of area?

Thank you very much

Stefano

Hi, I am simulating a horizontal axis wind turbine using Ansys Fluent. I want to validate the model by calculating the turbine power at different wind speed. Using Fluent, I calculate the torque and moment coefficient. But I don't know which equation must I use to calculate the power. Could you tell me which of these equation is the correct one

1- Power=Torque*angular velocity;

2- Power=Torque*angular velocity*Betz limit;

3- Power=Torque*angular velocity*Cp(=Ct*TSR);

4- Power=Cp*wind power;

5- Power=Cp*wind power* Betz limit ?

Thank you.

The tipping torque is balanced by one or more stability torques.

The tensile force in the cross section is neutralized by a compressive force.

A cutting force cuts the cross section but is neutralized when the cross section is under compression.

A small square cross section located on a high trunk bends easily.

A large cross-shaped cross section bends slightly.

A large cross-shaped cross section becomes almost completely rigid when we apply pressure to the cross section.

These are given laws of engineering.

The walls of the construction in the big earthquake, receive torques which often exceed three times the weight of the construction.

The walls and beams that are joined together at the nodes, receive torques (M), upright forces (N) (compressive and tensile) which cause bending, and shear (Q)

Civil engineers studying the response of the structure to seismic shifts had to apply compression to the wall cross-sections to increase their ability to withstand shear forces, bending forces, tensile forces, and prevent shear forces. failure of the coating concrete, which occurs due to the ultra-tensile strength of the steel.

I do not understand why civil engineers do not include in the study the imposition of compressive loads on the cross sections of the walls.

The high walls are high-lever arms that would tip over if they did not have the beams (with which they are attached to the joints) to hold them, and connect them to the other elements of the structure.

The beams have a resistance to bending which, if overcome, will break.

The lateral force of inertia creates the moment of inversion on the walls, while the beams react with opposite direction of momentum, in order to achieve balance.

If the overturning torque of the wall is greater than the reverse torque applied by the beam, then the beam will break.

1 + 1 = 2 If the opposite moments of the beams are not sufficient in large earthquakes, we can reinforce them with additional opposite moments, (derived from external factors) so that the sum of the opposite moments of the beam and the external factor is greater than torque of the wall, in order to achieve the desired balance of forces.

The second opposite moment of stability to the moment of inversion of the wall could come if we pressed the sides of the walls from their highest level with the ground.

I do not understand why civil engineers do not include the anchoring of the walls with the foundation soil in their studies.

Hello all, I modeled a simple torque on a shaft. The results should be linear but my contour plot shows the change to have only occurred through the first element of the shaft and not the entire shaft. The values of the output (UR, UR3) are correct, but the contour plot of the whole shaft should reflect the linear change seen in the legend not just the first element. I plotted the angle of twist along a path of nodes which confirms the increasing angle of twist is linear. Is there a way to get the contour plot to reflect this more accurately? The contour plot of the shaft should show the green color around the middle of the shaft, where the angle of twist is half the value of the max. Any thoughts? Kind regards,

RP

Hi everyone, I simulate a three bladed wind turbine using Ansys Fluent. The variation of wind turbine torque with tip speed ratio must have a peak. But in my case, as tip speed ratio increases , torque also increases.

How can I solve this problem ?

The relation between the number of the pole to stator slots its effect on the torque ripple.

Hello Everyone, I am simulating a small wind turbine using Ansys Fluent 19.0. Because of problem periodicity only one third of the fluid domain is simulated. The generated power is calculated using this equation: P=T*omega, with T is the rotor torque. My question is: the torque in this equation, is-it the calculated torque found by Ansys multiplied by 3 or only the calculated value ?.

Thank you.

I have hereby attached the excel file. Any suggestions or help are appreciated. Thank you in advance

The current electromagnetic torque of the synchronous generator is a consequence of its current magnetic circuit, totally dependent on the mutual rotor-stator inductance and therefore it is possible to minimize it, thus improving the input power.

Hello Community,

Do you have any idea or suggestion about, how to create Slip and Slide at Motor Shaft on No load Standalone setup for Induction motor ?

Shall i connect another Controlled motor at Test Motor Shaft with different torque (i fear of breaking shaft)

Or some else suggestion ??

Hello,

I am working on a project and we need to use an DC to AC inverter for the battery power supply. I am searching for devices that conver the current and also are capable of controlling the motor. I know that this kind of inverters can regulate the speed. But what about the torque? Does it need to be regulated with a variable resistor? How does it normally work?

Thank you a lot

Hello,

I am looking for a battery for a 70 kW BLDC motor. I want to be able to change the torque and speed of it. I understand that it is possible to vary the speed with the current frequency and the torque with the current amount. Does that mean that if I operate this motor manipulating the voltage but not the frequency am I going to be able to change the torque but not the speed? I want to know it because we don't need the full nominal performance of the engine at 70kW. Its nominal magnitudes are 420Vdc, 240A, 850Nm torque and 786 rpm speed. What should I do if I want to drive it at 425 Nm and same speed?

Best regards,

Jorge

Mass (kg) X acceleration = Inertia which is the same as the intersection of the base. The product of inertia if we multiply it by the height we find the overturning moment of the column. If we have a wall that has a double lever arm (except for the lever arm of height and that of width) then the product of the tipping moment is divided by the width of the wall and this will be the tipping moment of the wall. If the wall is anchored at its base, a reaction will be created to the overturning torque of the lever, which multiplies (as we have seen) the overturning forces, since, as the height increases, its overturning force also multiplies. If the anchor is at the bottom of the wall, the critical failure area will also appear there and the anchor point is also the lever of the wall. Question If the anchoring of the wall is not at its lower ends, but is at its upper ends. That is, if we place this wall on a machine - press and apply pressure to it, it will remain a lever arm or its mechanical condition will change; 1) Will we have a multiplication of the tipping forces as it happens when the anchor is applied to its lower extremities? 2) Will a critical area of ​​failure of right forces N (compression and tension) be created as it happens when the anchorage is applied to its lower extremities? In short, we know that the walls drop high torques at the base since that is where the reaction of any substandard anchorage is. If the anchoring is done on the roof (ie if pre-tensioning is applied between the upper ends of the sides of the wall and the foundation ground) it will lower torques at the base and will create or not a critical failure area;

I have a question on Cp in the wind turbine. I have calculated the moment in the z-axis as my rotor also rotors along the z-axis. I got the moment values from my simulation. I applied the procedure which ansys recommended formula (P= torque x rotational velocity) for extracting power from the turbine. I got huge discrepancies between actual and theoretical. After calculating power, I have calculated Cp it comes around 0.8 to 1, but the Betz limit is 0.59. plz help me to calculate the Cp.

Conditions :

Turbine Aera =17.5 m2

R=3.5m

V=3

omega=2.14 rad/s

TSR=2

Fluid water (990 is the density)

 

Hi everyone,

I created a 2-bladed VAWT model. The dimension is the same as the turbine used in the experiment.

I have run a 3D transient simulation via sliding mesh. The calculated torque from the simulation is close to the experimental data.

Now, I want to repeat it with the MRF approach. All the settings are the same (mesh, rotational speed, boundary conditions, turbulence model, solver). However, I couldn`t get a good result from the MRF approach. It has far deviated (negative value).

I read from literature, there are only small differences between the torque calculated from MRF and sliding mesh.

I`m just wondering did I miss out on some important steps?

I am looking for a software designer for my thesis. It looks like I will get a research grant to build the traction Simulator. I need a software designer to write the software for four inverters that will drive each wheel of a locomotive. The digital speed of each wheel must be compared with the master wheel and corrected immediately if there is a difference. Each gearbox will be fitted with a digital encoder output. The inverters must be Direct Torque Controller type. (DTC) and the motors must be 3-phase permanent magnet motors.

If you are interested then please email me at bschaffler@schafflerconsulting.com and i will send you detailed information. This system will not accept a drawing from me.

Hi,

I wonder how torque changes with different angles of the torsion axis. Please find the attached figure. I can see how to find out T1 (Blue colour) but not T2. Do I have to compare cross-sectional areas? It would be great if someone can share your thought on this or any formula on this.

Regards

Dear researchers,

while replacing fuzzy with speed PI control for PMSM drive, speed is tracking fine but whenever the load is applied speed is drastically reducing.

If torque limits have of output membership function chosen as >1500 or above and (placed a limiter at output (+-20 because rated torque 20N-m)found no decrement in speed but torque ripple is there. What could be the possible reason.

How to select the range, we must select the range of output membership function between +-20 right?

7*7 base rule base only considered for error and change in error that usually all the people mention in paper.

does speed settles back in fuzzy even under load or it maintains steady state error?

Please share your experience.

Thank you.

Does the motor rating have effect on the performance of maximum torque per ampere strategy? Are there any references on this issue?

The inevitable inelastic behavior of structures under strong seismic excitation leads to flawed failures, because the existing anti-seismic design does not have the required technological knowledge and the mechanisms needed to be able to control inelastic deformation and adjust it so that it is always present. within the elastic displacement phase where no failures occur.

The magnitude of the seismic acceleration, which reaches under the construction, the duration of the earthquake, the unknown number of seismic excitation frequencies, the direction and the magnitude of the oscillation amplitude of the seismic waves, are some of the factors that determine the behavior of structures, and shape the size of the disasters.

A building withstands high ground acceleration for a short seismic duration, or low seismic acceleration for a long duration. However, it does not withstand large seismic acceleration of the ground for a long time.

The seismic technology of the constructions has advanced technologically in the management of the inevitable inelastic behavior of the constructions, by solving the correct design of the cross-sections around the nodes and the planned plasticity.

However, leaks - failures that occur during the inevitable inelastic deformation, are fragile reference points and indelible imprints of damage, which help the next earthquake to complete the catastrophic work of the previous one.

If we can control the displacement of the structures dynamically and force them to deform only elastically, (without allowing them to deform, inelasticly) then there will be no failures and collapses of buildings.

Unbalanced seismic factors are rare, likely to occur, and reassure us, but they do exist and can hang even the most modern seismic structures.

ON THE SUBJECT

The applied research I conduct is based on finding these appropriate design methods and the appropriate mechanisms by which it will be possible to control the deformation - displacement of buildings under strong seismic excitation.

During rocking, the structures can be deformed in the elastic area where there are no failures, but we will have the control so that they never pass in inelastic brittle displacements.

The new method of seismic design that I present, controls the deformation of the structure, regardless of the magnitude of the acceleration, its duration, and the unknown number of frequencies of seismic excitation.

The mentioned seismic system stops the eigenfrequency - tuning

By the method of designing the application of compressive stresses on all sides of the wall cross-section, (using for this achievement unrelated prestressed tendons and hydraulic traction systems) as well as by joining the same tendons to the foundation ground, (using for this achievement strong expanding piles placed and firmly anchored in the ground,) I hope to deflect the lateral inertial stresses (causing overturning and bending and receiving the walls,) to stronger areas than those currently driven.

These strong areas have the ability to absorb these stresses, preventing relative inelastic displacements and wall overturning,

(causing brittle deformations at the junctions,) with the result that the intensity that develops throughout the structure of the building is limited.

The unrelated tendon of the mechanism, in cooperation with the cross section of the wall, receive the tensile and compressive forces (coming from the overturning moment of the wall and the bending of their trunk) and deflect them into the ground from where they came from, removing thus great tensions and failures over the load-bearing structure of the building.

It is an expanding stake mechanism, which primarily pushes strongly into the ground, to draw force from it, which it transfers with the help of tendons to the upper ends of the sides of the wall, in order to create a moment of stability, equalizing and balancing the overturning moment of the wall.

This moment of stability applied by the mechanism has no mass, because it is a force coming from the ground, so it does not create additional tensions of inertia.

Adds dynamics to the construction without increasing the intensities.

At the same time, it provides a stronger bearing capacity of the foundation soil, due to the strong anchoring of the mechanism, which is an expanding foundation pile.

With the proper dimensioning of the floor plan of the walls and their placement in appropriate places, we also prevent the torsional buckling that occurs in asymmetric and metal high-rise structures.

The application of compressive forces to the cross section of the wall using the tendon mechanism, has the effect of reducing the bending of the trunk, and increasing the ability to receive the shear.

These are two other factors that contribute to the deformation on the one hand and to the failure that the design method prevents on the other.

The bilateral connection of the sides of the walls from their upper end to the ground helps to prevent the overturning torque, which in combination with the bending results in the creation of torques at the nodes which cause the shear failure of the cross-sections.

The result of the prestressing applied to the cross section of the wall is the result of the percentage improvement of the shear as well as the reduction of the tensile stresses in the cross section to a point that does not exceed the cracking tendency.

Therefore the concrete does not crack, nor does it bend inelasticly, it simply shifts elastically.

Pulsars are subject to a systematic secular spin-down. It is well-known that the electromagnetic torque is responsible for the rate of change of the rotational frequency. The braking index is obtained in terms of the second time derivative of the rotational frequency. Any deviation from the canonical value of 3 is given in terms of the SECOND time derivative of the moment of inertia.

Alternatively, the rate of energy loss can be expressed as a secular variation in the moment of inertia. The rate of energy loss is the square of the second time derivative of the moment of inertia, making it a 4th power of the rotational frequency, again resulting a breaking index of 3.

Now, for gravitational radiation it has been claimed that the rate of energy loss yields a value of 5, the rate of energy loss is portional to the 6th power of the rotational frequency. If it could be expressed in terms of a "gravitational" torque, that would mean a torque proportional to the cube of the frequency, and not a squared as in the expression for the centripetal acceleration in the electromagnetic case.

How can this be accounted for by a breaking index whose deviations from the canonical value of 3 is only a function of the SECOND time derivative of the moment of inertia and not the third? It would therefore appear that electromagnetic and gravitational radiations cannot be interpreted by the same breaking index yet both should apply to pulsar spin-down.

.

Dear all,

I want to clean cylindrical pipe with a steel brush that I have attached in the picture. Now I want to calculate the torque required to rotate the brush inside the cylinder. Can anyone let me know the procedure or suggest me some literature on same.

All civil engineers know that inertial stresses create deformations that cause failures and collapse of structures. Deformation can be caused by three different factors 1) The greatest deformation is created by the overturning moment of the wall and by the bending of its trunk 2) The second deformation is created by the torsional buckling that is observed in asymmetric, in high-rise constructions and in metal constructions. 3) The third deformation is created by the inhomogeneous subsidence of the ground (with or without earthquake), which deforms the nodes of the structure. THE SOLUTION 1) The walls under the imposition of compressive stresses on their cross sections through prestressing, do not create a bending deformation capable of creating shear failures. Conclusion Pre-tensioning must be applied to the walls. However, the prestressing increases the already great rigidity of the wall, and this has the effect of lowering (like a strong lever that it is) large torques at the base and at the nodes where it is connected to the beams, causing them to break. That is, as rigid, the wall is easily overturned and creates large moments at the base and at the nodes where it is connected to the beams, resulting in their breaking. Conclusion In order not to overturn the wall, we must connect it with the ground 2) Proper dimensioning of wall sections as well as the imposition of compression on their sections reduce torsional buckling 3) We must improve the quality of the soil by compacting its material, if we do not want subsidence The patent applies anchoring to the ground, compacts it, applies compression to the wall cross-sections and stops wall overturning, wall bending, torsional buckling and ground subsidence. What else do you want the patent to do, other than control the deformation that causes failures?

I have torques and angular positions data (p) to model a second-order linear model T=Is2p+Bsp+kp(s=j*2*pi*f). So first I converted my data( torque, angular position ) from the time domain into the frequency domain. next, frequency domain derivative is done from angular positions to obtain velocity and acceleration data. finally, a least square command lsqminnorm(MATLAB) used to predict its coefficients, I expect to have a linear relation but the results showed very low R2 (<30%), and my coefficient not positive always!

filtering data :

angular displacements: moving average

torques: low pass Butterworth cutoff frequency(4 HZ) sampling (130 Hz )

velocities and accelerations: only pass frequency between [-5 5] to decrease noise

Could anyone help me out with this?

what Can I do to get a better estimation?

here is part of my codes

%%

angle_Data_p = movmean(angle_Data,5);

%% derivative

N=2^nextpow2(length(angle_Data_p ));

df = 1/(N*dt); %Fs/K

Nyq = 1/(2*dt); %Fs/2

A = fft(angle_Data_p );

A = fftshift(A);

f=-Nyq : df : Nyq-df;

A(f>5)=0+0i;

A(f<-5)=0+0i;

iomega_array = 1i*2*pi*(-Nyq : df : Nyq-df); %-FS/2:Fs/N:FS/2

iomega_exp =1 % 1 for velocity and 2 for acceleration

for j = 1 : N

if iomega_array(j) ~= 0

A(j) = A(j) * (iomega_array(j) ^ iomega_exp); % *iw or *-w2

else

A(j) = complex(0.0,0.0);

end

end

A = ifftshift(A);

velocity_freq_p=A; %% including both part (real + imaginary ) in least square

Velocity_time=real( ifft(A));

%%

[b2,a2] = butter(4,fc/(Fs/2));

torque=filter(b2,a2,S(5).data.torque);

T = fft(torque);

T = fftshift(T);

f=-Nyq : df : Nyq-df;

A(f>7)=0+0i;

A(f<-7)=0+0i;

torque_freq=ifftshift(T);

% same procedure for fft of angular frequency data --> angle_freqData_p

phi_P=[accele_freq_p(1:end) velocity_freq_p(1:end) angle_freqData_p(1:end)];

TorqueP_freqData=(torque_freq(1:end));

Theta = lsqminnorm((phi_P),(TorqueP_freqData))

stimatedT2=phi_P*Theta ;

Rsq2_S = 1 - sum((TorqueP_freqData - stimatedT2).^2)/sum((TorqueP_freqData - mean(TorqueP_freqData)).^2)

I am sure they have understood that I am trying to deflect and return the developing seismic forces into the ground from where they came from before they developed on the construction site.

I stop the torque - moment of inertia and the bending of the wall, just as you stop in the air, the cantilever of a prestressed valley bridge.

You send the torques to the pedestal and I send them to the ground.

I am still trying to create anchoring conditions with a deep anchoring mechanism that expands with a hydraulic jack and fill the hole after anchoring with concrete.

If the anchorage is not enough I go deeper into the ground.

Although this is not enough, then create a bundle of anchorages with a headband.

This is what the tree with the roots does in nature.

The forces of action and reaction are real but not visible.

The overturning momentum of the wall is real and is nothing more than a force that tends to rotate the wall around the hinge of its base, just as the car wheel rotates around the axle.

To achieve balance and stop the rotation of the wheel we use the brakes, that is, a force equal to and opposite to this force that causes the rotation of the wheel.

That's what I do too.

At the moment of inertia of the wall (the moment of inversion) I create a moment of stability coming from the ground.

You do the same.

In the moment of inertia - overturning of the wall, a moment of stability is opposed derived from the cross-sections of the load-bearing elements around the nodes (capable cross-sectional design)

Our difference is that the power of the invention comes from the ground, which is an external source, while the other from the reaction nodes.

The external torque transmitted to the carrier by the mechanism of the invention has the advantage that it has no mass and has unlimited strengths, while this cross-sectional reaction has its limits and multiplies the tipping moment since it has mass which creates the inertia force from where the tipping moment comes from. https://www.youtube.com/watch?v=zhkUlxC6IK4

Hi everyone,

I have a conceptual question related to reinforcement learning that might be of interest to many people. Suppose we are dealing with the driving problem. There are several ways to define the actions: a) we can define the actions based on the accelerator, steering wheel, and brake, that is, where your body meets the machine? b) or where the rubber meets the road, considering your actions to be tire torques. c) where to drive?

As summarized above, there are many ways to define the actions or, in other words, draw the lines between the agent and the environment! How can we choose proper action lists for a given agent? In other words, how can we draw a boundary between the agent and the environment?

Thanks in advance for your insightful comments.

I can see viscosity, torque, and speed values on the display but shear rate and stress are displayed as 0.00. can anyone help me to understand why this is happening?

To have a torque with reduced ripples is it better to have current signals with square shape or better to have it with sinusoidal shape?

Good day,

I doing research on electronic controlling a wind turbine. The generator used is a small permanent magnet synchronous generator. I have a question regarding the Torque Speed curve. I have taken an example figure for clarification [1] with a torque and speed curve. Suppose there is a wind speed of 12 m/s. The MPPT system of the inverter should ensure the operating point where power is at its maximum shown as a yellow dot. Now the generator has a torque limit that should not be exceeded. In the example shown as a red line. To protect the generator I should implement an electronic brake (brake chopper with a braking resistor). When the brake is activated some power is dissipated in the braking resistor.

My question is, what I do not understand is: will the operating point on the speed-torque curve do? Will it follow the 12m/s curve to the right, to the left, or could the operating point move off the line, downwards or somewhere else?

Thank you for your time.

[1]

The force of the earthquake shifts the construction back and forth creating torque on the walls.

The tipping torque is the opposite of the stability torque.

The tipping torque rotates the wall around the base joint.

In order to balance a wall from overturning, we must impose stability forces equal to or greater than the overturning torque.

A wall that extends in height from the base to the last slab on the roof, is a huge lever arm.

This wall has all the characteristics of a lever arm, such as multiplying and lowering high torques at the base, having a critical failure area, being subject to shear failure.

What I will tell you below is my research and is being applied for the first time worldwide.

1) I built a mechanism that joins all the ends, of the cross section of a wall, from the top level, together with the ground of the foundation, in order to create a moment of stability to balance the overturning torque of the wall.

The force that creates the moment of stability comes from an external factor, that of the foundation ground.

This means that this force does not come from the load-bearing structure of the building, so it does not have a mass that increases the inertia forces.

So we have the ability to increase the stability force indefinitely without increasing the inertia of the building.

The current state of science to balance the tipping moment of the wall uses the cross sections of the load-bearing elements which are joined together at nodes, to apply stability moments to the wall.

But when the earthquake is large and the acceleration of the ground is large, in conjunction with the height of the mass and the size of its weight, they increase the force of inertia and the moments of tipping, and the cross-sections break.

If we increase the cross sections to be stronger we increase at the same time the mass and then the inertia forces.

For this reason it is very important that I introduce for the first time worldwide on the construction, an unlimited power moment of stability without mass, to additionally help the moment of stability of the cross sections around the nodes.

2) The size of the tip torque of the wall lever depends ...

a) by the magnitude of the inertia force (resulting from the acceleration of the ground and the weight of the mass of the structure)

b) from the height where the mass is from the ground

c) From the dimensions of the wall in height and width.

Let's take an example.

A wall 10 m high and 3 m wide receives an inertia force at the top of 50 tons.

What will be the magnitude of its tipping torque?

Inertia force X height / width 50 X 10/3 = 166.7 tons.

That is, the mechanism of the invention together with the cross-sections of the nodes should together create a moment of stability greater than> 166.7 tons so as not to overturn the wall.

Here we see that the width of the wall works beneficially in reducing the force of the tipping torque.

If we had columns instead of a wall, the tipping moment would be three times greater!

Conclusion In large walls and buildings made entirely of reinforced concrete, the patent is more efficient than in columns.

Basically a large moment of stability is created by three contracting aggregates, such as that of the patent mechanism, that of the wall width and that of the cross-sections, around the nodes.

3) Another factor that causes deformations is the bending of the trunks of the bearing elements.

The bend is created by the elastic and inelastic deformation of the body of the elements during the displacement of the floors

There are two methods to stop the deformation caused by the bend.

a) Place large walls instead of columns that bend easily.

b) Apply a similar amount of compression to the cross sections of the walls to eliminate the tensile strength of the walls.

Without tension there is no bending.

The necessary strength of the sections so that they can absorb the additional compressive forces is ensured by the quality of the concrete,

from compacted concrete,

from the sufficient coating concrete, but mainly from the size of the cross-section which the wall has sufficiently.

The compression in the sections is applied by the mechanism of the invention, stopping any bending of the wall.

Without bending, there is no shear failure in the cross section or shear failure in the coating concrete, caused by the ultra-tensile strength of the steel.

Stress in the cross-sections also improves their resistance to the cutting base, improves the trajectories of the oblique tension and increases the active cross-section of the wall.

4) The soil compaction mechanism ensures a deep foundation (better than this base in width) by improving the bearing capacity of the soil.

The drillings that we have to do for the installation of the mechanism, reveal to us the quality of the soil, as well as the dangers that the soil hides, such as caves and running groundwater which can gradually remove the foundation soil causing landslides.

What am I trying to stop with the method of seismic planning that I propose?

I try to stop the distortion.

That is, the inelastic displacement.

I try to stop the moments at the nodes that break the cross sections that create the node.

I try to strengthen the loose foundation ground.

I achieve all this by pre-tensioning + anchoring all the sides of the walls with the foundation ground.

If the earthquake is large and lasts and coincides, the construction period and the ground and coordination occurs, then no regulation is sufficient to deal with it without at least serious damage to the construction.

Only the design method I suggest. It can even stop the coordination of the construction in each charging cycle.

Many times in my posts I refer to the overturning of the walls.

These walls are not independent to overturn.

They form a single framework with the other elements of the carrier organism.

They are not in danger of overturning.

Nevertheless.

Any change in the vertical axis of the walls, either by bending or by overturning, also affects the curvature of the beam logs since they are connected at the nodes.

The result of the prestressing on the sides of the walls, is the reduction of the tensile stresses in the cross section to a point that does not exceed the realization tendency.

Therefore, the trunk of the wall bends elastically but does not crack.

If by pre-stressing the sides of the walls, we increase their resistance to bending and reduce the curvature of their trunk and by anchoring them to the ground we prevent them from tipping over before the stresses go to the beams, the beams will take on less tension.

The walls are obviously not in danger of tipping over as they form a single frame with the other elements of the load-bearing structure.

But in order not to overturn the walls, the beams create opposite torques.

If the seismic energy (measured by ground acceleration) is too high, it will produce excessively large displacements in the walls, which will cause a very high curvature in their beams.

If the curvature is too high, this means that the rotation of the beam sections will be well above the elastic area (Concrete deformation over 0.35% and reinforcement fiber stresses over 0.2%) beyond of the leakage limit.

When the rotation exceeds this limit of elasticity, the beam begins to "dissolve the energy storage" through plastic displacement, which means that the parts will have a residual displacement that will not be able to be recovered (while in the elastic region all displacements are recovered).

The result is, if the beam passes the pt. break point to break and have a problem.

The issue is not whether there are moments in the wall, but where you direct those moments. With the method I tell you I direct the torques (correct compressive and tensile forces) into the ground while you direct them to the cross sections of the beams which after bending break. Directing most of the torque into the ground contributes to less stress on the beams.

Pre-tensioning the wall eliminates the bending moment and the anchoring of the construction to the ground with expansion piles transfers the torque into the ground. https://www.youtube.com/watch?v=IO6MxxH0lMU

The acceleration of the ground, the mass of the structure, and the height of the mass from the ground, are the three factors that create the magnitude of the lateral seismic force. This lateral seismic force tends to overturn the walls of the building. The walls of the high-rise floors are rigid, and drop heavy torques at the base. Question If, with unrelated tendons, we apply pre-tension to a wall between, the upper ends of its sides and the foundation ground, then, it will lower torques at the base;

Can MR brake or MR clutch can replace the conventional torque transmission system in automobile.

vertical axis wind turbine is rotating with a known RPM. Practically, how to measure the torque by utilizing the rotating shaft attached to the turbine?

The problem is this: there is model of robot, created in Simscape. And knee of this robot is made of "pin-slot-joint", which allows one transnational and one rotational degree of freedom. In transnational motion, it is imposed the stiffness and damping factor, which gives influence also to rotational torque. My aim is to write optimization or control algorithm in such a way that this algorithm should provide such stiffness(in linear direction), which will reduce the rotational torque. By the way, rotational reference motion of knee is provided in advance(as input), and appropriate torque is computed inside of the joint by inverse dynamics. But to create such algorithm, I have no deep information about block dynamics, because block is provided by simscape, and the source code and other information is hidden. By having signals of input stiffness, input motion, and output torque, I need to optimize the torque.  I will be truly grateful if you suggest me something. (I tried to obtain equation, by using my knowledge in mechanics, but there are lots of details are needed such as the mass of the joint actuator, it's radius, the length of the spring and etc. AND I HAVE NO THIS INFORMATION.) If you suggest me something, I will be truly grateful.