Combustion Analysis - Science method

Ya I went through several texts but couldn't find anything concrete for 0d while things are more sorted out when considering 2d or similar systems. As mentioned, for 0D as there is no fuel and oxidizer stream as such, defining mixture fraction doesn't seem to be clearer

I am interesting

full paper

Dear Francesco

Thank you very much.

Regards

Hi,

We're in the process of validating a new method for simulating reacting flows, and have been taking it step by step, starting from scratch only recently. The model may not be of interest to you, but the test cases should :

- [1] > 1D premixed flame, 1 step, constant Cp

- [1] > 2D counterflow diffusion flame, 1 step, constant Cp

- [2] > 1D premixed flame, NASA Cp, detailed chemistry

- [2] > flame vortex interaction, 1 step

- more complex cases in subsequent publications

Refs (on RG)

[1] Y. Feng, M. Tayyab, and P. Boivin, “A lattice-boltzmann model for low-mach reactive flows,” Combustion and Flame, vol. 196, pp. 249 – 254, 2018.

[2] M. Tayyab, S. Zhao, Y. Feng, and P. Boivin, “Hybrid regularized lattice-boltzmann modelling of premixed and non-premixed combustion processes,” Combustion and Flame, vol. 211, pp. 173–184, 2020.

Essayer de faire le bilan

Dear Sven Eckart ,

You can get the data asked in the below publication. Check the section radiation model Table 4

I appreciate for interest. You better come to developing countries like Ethiopia. You will get a chance to compare such problems with developed one.

@Henanth,

The short answer to your question (if read strictly and literally) «Is there any mathematical equations (…) (for computing) the relationship among exhaust temperature (…) (and) the rate of heat release and heat lost to the surroundings?» is: no.

However, there is an obvious direct correlation between the amount of heat (i.e., thermal energy) released and the EGT:

(H_combustion – Q_loss) = m_gases x (cp_exhaust x EGT – cp_mixture x T_intake).

But not the rate (power).

I.e., if you mean to ask if there is a simple analytical relationship between the heat release rate (HRR) of a combustion reaction inside the combustion chamber of an ICE and the exhaust gas temperature (EGT) (before the turbocharger turbine is irrelevant for the current purpose), the answer is clearly no. You see: since exhaust happens after combustion is complete (not strictly true in every case, but… let’s simplify), the HRR (or the “quickness” that heat is released with) has no direct relation with EGT (which doesn’t mean that there is no correlation; there is a correlation, but it’s minimal and more complicated).

The HRR surely influences the amount of heat dissipated through the combustion chamber walls, since this depends on time (of exposure). But this is not easy to model at all. The highly dynamic and non-adiabatic internal environment of an ICE combustion chamber is still very difficult to model with precision. Also, the number of variables that might influence EGT in an non-adiabatic chamber is massive, e.g.: area, volume, geometry, temperature, thermal conductivity and heat capacity of the chamber boundaries (which are not uniform, btw), rate of expansion (directly from the RPM and engine geometry)… etc… not to speak of combustion dynamics and fluid dynamics, which are another “can of worms” altogether…

Adiabatic models are much simpler and can, frequently, give us adequate results, within their clear limitations. However, if we ignore the heat dissipated through the combustion chamber boundaries, then the EGT has nothing to do with the combustion HRR, whatsoever…

Concluding, there’s no quick and straightforward way to compute/calculate the HRR solely on the EGT or vice-versa. Even if that is virtually possible, you would have to build a rather complex model, based on several differential equations only solvable by numeric (iterative) methods. Quite a mess…

Nevertheless, it would be virtually possible to fit an empirical mathematical model to a *specific* engine, once it is sufficiently tested and measured, and the relevant covariates are identified. But I have serious doubts about the feasibility of such endeavor…

I may, however, have misunderstood you. I’m still not 100% sure I got you right. If that’s the case, please let me know.

Dear Loke,

AVL boost, DIESEL-RK, GT power, converge are more common.

Simplest is LabView software package, significantly less expensive than state-of-the-art commercial programs. this can be used.

Ashish

Hi,

Getting a research position in IC engine or in any specific field is completely dependent on the hiring professor at a particular institute. If he is having funding and project, then he would probably hire a candidate at any level (graduate or postgraduate). However, there are still lots of scope in engine and fuel research and it is not possible for the electric vehicle to replace it completely considering the economy, reliability and other factors. In India, almost all old IITs and IISc are having very good engine research labs. You can contact individual faculty through email. I hope this will help you.

Thanks!

-Arnab

IIT Madras.

Hi

It depends on different factors. you can compare the actual cycle with the Carnot cycle efficiency. You can write a suitable code in EES software to this purpose.

Knock obviously is abnormal combustion may occurs in spark ignition due to several causes ( high compression ratio; air_fuel mixture low octane number of fuel flame speed

You can use the equations mentioned in the attached paper. Even you can calculate it as a function of temperature.

Deflagration and detonation refer to combustion. In the nuclear explosion, the energy is not released due to combustion, therefore neither of the two terms is appropriate to describe it.

Hi Ahmed, renewable energy is a type of energy which is inexhaustible, while energy efficiency deals with utilising the existing energy irrespective of renewable or non renewable, judiciously. that is, getting the work done with less expenditure of energy without the loss of quality. For example a bulb that draws 3W of power to light a room compared to the similar bulb that draws 5W power to light the same room, is considered to be energy efficient. further if the same bulb utilises electricity obtained from fossil fuel, it is considered to be energy from non renewable source. If the same power is obtained from water or wind energy thn it is energy from renewable source.

hope it helps!! :/

I am happy I could help. Best of luck for your research

heyy

did u find file for diesel in chemkin

C-J is the simplest theory to deal with it - more advanced theories are ZND and Wood-Kirkwood.

The Chapman-Jougeut equations or, more precisely, the ZND models describe both detonation and deflagration events and provide quantitative estimates of how they are distinguished. These equations are widely published. These include the following conditions, which can be experimentally or numerically explored

1. A detonation proceeds at sonic velocity or higher relative to the unburned gases. A deflagration proceeds slower than this, generally much slower.

2. Detonations produce much higher peak pressures.

3. Detonations generally proceed through pressure-driven decomposition of the reacting gases whereas deflagrations proceed via chemical reaction.

4. Detonations release the same amount of energy as deflagrations of the same material, but the energy release is much faster.

Colloquially, any explosion is generally called a detonation. However, most are actually deflagrations. Since both can be highly destructive and both generally lead to explosions of something, they are often equated or at least not distinguished. Deflagrations produce lower overpressures and therefore less dramatic changes in all gas properties and less overall chaos than detonations of the same material. Detonations and deflagrations commonly produce shock waves that propagate from their point of reaction, but these waves are, themselves, not detonations or deflagrations unless they are driving reactions in the materials in front of them. They may be generated by deflagrations and detonations, but the technical use of these terms supposes there is some sort of heat release occurring as the event proceeds. Therefore, a shock wave, regardless of strength, is not a detonation or a deflagration, though it may be caused by either one of these.

Deflagration-based explosions generally result from reaction in some sort of closed vessel, which overpressures the vessel to the point of physical and catastrophic failure. This failure produces a shock wave and is the explosion. A detonation can do this as well, but a detonation does not require any closed container. It propagates through the reactants with increasing Mach number without the need for a confining chamber to establish sonic or supersonic velocities or pressure ratios.

A good source to start will be: Bayvel L., Orzechowski Z., 1993. Liquid Atomization.

Also find these papers...

Recommend the answers if found helpful.

ic engine internal temperature vary from 1800 C to 2300 C and may reach up to 2700 C but it may be under overheat condition

Interesting question on combustion analysis

Hi Raj,

If you have access to a software HYSYS or AspenPlus, you can simply enter the chemical composition that you specified and the simulation software to calculate the enthalpy of the biochar. You can download at a no cost a trial version of HYSYS or AspenPlus from Aspen technologies at:

Best,

Prof. Khalil

We have used automotive high pressure gasoline direct injection fuel injectors to inject gases into pressure vessels.   If you are not using them continuously for many hours per day, over many weeks they will maintain their flow rate.   That is they do not seem to wear the pintle and seat of the injector rapidly, even though it is injecting a dry gas, instead of a liquid fuel.

Thanks a lot for your contributions and advice references 

The data obtained from the experiments conducted were collected from relevant sensing setup using the instrumentation automation software package (LabView). Data batches collected were migrated to (Matlab) in order to process the data to obtain related values for peak pressure and the accompanying angle at which peak pressure occurred, the angle between start of combustion (SOC) and peak pressure, and to estimate the amount of apparent heat release rate (AHRR). The mathematical processing was carried out using an elementary methodology using the conventional first law heat release model assuming a constant specific heat ratio of 1.35 without any accompanying modeling of heat transfer or crevice effects. While this method was very elementary but was found to be adequate for conducting comparisons.  For the purpose of ensuring that a constant value cp/cv could represent both fuels satisfactorily, an approximation of the cp/cv values made from the charts of logarithm of pressure / logarithm of volume were used in the conducted calculations.

Figure (2) demonstrates the definitions upon which the AHHR parameters calculations were based. For the purpose of reducing noise effect on the obtained results and maintaining the crucial characteristics of combustion, each pressure point on the trace was calculated from averaging every 100 cycle pressure data. The data acquisition system logged pressure data once for every degree of crank angle, but these data were interpolated to one decimal place by a program written to run under (Matlab) .The combustion criteria parameters listed in the points after the following paragraph were calculated using the AHRR curve of figure (2) without any filtering or averaging except for the end of combustion value and the end of premixed burn. The end of combustion value was outlined using the moving average of the AHRR for the purpose of improving its consistency. The end of premixed burn was calculated from the second derivative of the AHRR. The following points list the combustion criteria calculated from the AHRR curve:

1. Start of injection (SOI): this factor was defined from the instructed SOI set within the engine management software. Any impending difference between the instructed and actual SOI is possible due to solenoid delay and should be uniform in conducted measurements as the engine speed was maintained constant.

2. Ignition delay (ID): the value of ID is defined as the difference between the instructed SOI and calculated SOC.

3. Start of combustion (SOC): the start of combustion is defined as the point at which the heat release rate becomes positive. On the AHRR curve, it is defined as the point where the curve crosses the x-axis.

4. Premixed burn Fraction (PMBF): the value for this factor is calculated from dividing the Integral of the AHRR curve between SOC and EOPMB by the Integral of the AHRR curve between SOC and EOC.

5. End of premix burn (EOPMB): the end of premix burn is defined as the first point at which the second derivative of the AHRR reaches a local maximum following a global minimum. In most conditions, the value of this factor approximates the one that corresponds to the position at which the AHRR curve reaches its first local minimum after a global maximum. But in this study, the second differential was used instead due to the reason of unclear local minimum in the AHRR curve under low load conditions which can be observed in figure ( ).

6. End of combustion (EOC): this point can be defined as the first point at which the moving average of heat release rate drops below zero. The moving average was used to minimize the noise impact on the results accuracy while keeping its representative consistency with the general tendencies of collected data. Additional characteristic values can be calculated from the in-cylinder pressure data, these include: the total

apparent heat release, peak AHRR, angle of peak AHRR, angle between SOC and peak AHRR, PMBF, 10 – 90% burn fraction intervals, duration of partial burn fraction intervals, and average burn rates through partial intervals. Emissions data averaged over 180 s durations were recorded.

you can see my paper

An Investigation of the Relation Between Combustion Phase and Emissions of ULSD & RME Biodiesel with a Common-Rail HSDI Diesel Engine

Hi!

see the following reference. it may help you

Regards

Ridha

Hi,

   Thanks for your reply. But how can i get U' in the passage from the U' in the combustor?

Many thanks for your answer, even without the detailed you required, and that I missed to write.

I am studying lean combustion of methane (equivalence ratio 0.65-0.85). The operating pressure might reach 4 or 5 bars, depending on the operation point we decide to carry out, in the end. The maximum temperature measured in the combustor for a global equivalence ratio of 0.65 is 2000 K.

The idea of using a dye might result in less fouling of the optical windows, but I am not sure whether a dye can survive the flame front. I'll investigate futher.

Best regards

The efficiency of any heat engine is maximized by raising the inlet temperature Thot and lowering the outlet temperature Tcold. For example the Carnot efficiency is 1 - Tcold/Thot and for the Curzon-Ahlborn efficiency is 1 - (Tcold/Thot)^1/2.

Dear Pranav Kherdekar

This information is possible important for you.

A system for estimating engine exhaust pressure includes a pressure sensor fluidly coupled to an intake manifold of the engine, a turbocharger having a turbine fluidly coupled to an exhaust manifold of the engine, a control actuator responsive to a control command to control either of a swallowing capacity and a swallowing efficiency of the turbine, and a control computer estimating engine exhaust pressure as a function of the pressure signal and the control command. In an alternate embodiment, the system includes an engine speed sensor, an EGR valve fluidly connected between the intake manifold and the exhaust manifold, and an EGR valve position sensor. The control computer is operable in this embodiment to estimate engine exhaust pressure as a function of the pressure signal, the control command, the engine speed signal and the EGR valve position signal.

Sincerely,

Luis Tipanluisa

You can perform the heat balance test on the engine. Though its not a 100% accurate, but it does give you an idea about the heat lost to coolant and heat lost in exhaust gasses. You would still end up majority of the portion in unaccounted loss. 

Dear Rupam,

a realistic result implies the use of 3-D models and as mentioned previously a finite volume approach (using a software) is appropriate. however, if you want to consider simple case of homogeneous surface temperature at steady state you can apply the energy balance at the inner surface and use an energy balance at the outer surface in order to determine the temperature of the inner surface. in your case, once can assume that the temperature (in cylindrical coordinates) doesn't depend on teta (angle) nor the radius because normally you have a thin wall. the only variable is z ( the vertical distance). thus if the cookstove height isn't much, you can look then for a (one) temperature of the interior wall. I repeat, this is only due to previous assumptions and to simplify the equations.

next step would be to determine the flame temperature (assumed adiabatic flame temperature) by using the chemical reaction between the fuel and air and determining the combustion products compositions. then the flame temperature will be used for the radiation part in the energy balance at the interface where you need to add the convection part. the convection part is determined based on Nusselt correlations for internal convection, you have the mass flow rate and the cross-section of the cylindrical combustion chamber, thus you can calculate Re and based the thermo-physical properties of the exhaust gas (for simplicity, it might be assumed as air), you can deduce the average heat transfer coefficient.

It is interesting to compare the results of 1-D simple model with the finite volume (3D-model). Good luck.

Kind regards,

Kfiah SARRAF

For calculating compression ratio you should know the swept volume and clearance volume of the engine cylinder. Then you can use the relation,   r= 1+(Vs/Vc). Where, r- compression ratio, Vs- Swept Volume and Vc- Clearance Volume.

maybe these links are useful to you:

As Prof Khalil points out the reverse water gas shift reaction is a good way to produce CO from CO2 and H2 given a high enough residence time it will go to equilibrium at temperatures of 400 F or higher over Cu, Ni or Fe catalyst.  If you need to product CO2 ffree was you will need to scrub out the CO2(an acid)  with an amine or other appropriate (eg Carbonate) material

I have no problem solving the problem. From the error message of the original, it might be out of memory, which implies you need to have more memory size.

You can detect the effect of flame thickness using pyrosym software ..and Ansys combustion package software

Sokolik, A S Self-ignition, Flame and Detonation in Gases. Here short description of cool flame, blue flame and hot ignition.

You need to see something like this: "low temperature ignition"

for example: http://frolovs.ru/pdf/2016-25-eng.pdf.

The mean effective pressure(mep) is a usefull relative engine performance measure and is obtained by dividing the work done per cycle by the cylinder(s) total displaced volume per cycle.

Hi Rajesh,

I am using the NASA/CEA code to calculate equilibrium states of a premixed flame propagation. I can say to you that is a good choice.

It is not clear to me if you're intending to use the on-line version or the code version in FORTRAN, JAVA, etc. I recommend to work with the code version, that will provide higher versatility to your projects.

As you are dealing with a free flame I suggest two steps:

1 - calculate a "tp" problem, using the fuel, phi, initial pressure and temperatures as input;

2 - calculate a "hp" problem, that means a constant pressure and enthalpy combustion. The inputs are the initial pressure and the enthalpy (normalized by the universal gas constant) obtained in the step 1.

You can set the number of species of interest for the "hp" problem, considering dissociation of the burned gases. In my case, I considered 9 species that we elected as more likely to be present in the burned gases.

I've attached two examples of input and output files for the "tp" and "hp".

I hope it will help you.

Best wishes,

Ricardo.

Human temperature perception is a difficult thing: as the body interacts with the environment (per sweating), even a change in air flow results in a change of temperature perception. (search for "chill factor")

So a change in air flow will immediately result in a change of temperature perception. Regarding the stop of AC, this may or may not be overlayed by effects of direct radiation absorption, which could easily dominate any change in 'objective' air temperature.

Hi Carlos

Ridha's answer is interesting but to calculate the burning velocity in a large burner you need a good software and a good computer.

The relations between turbulent flame velocity an kinetic reactions rates are not simple.

You can build a burner without kinetics.

Best regards

Mr Jeryrajkumar

The standard values depend on the standard with which they are compared. There is the European and American standards. In addition to the properties that you measure is cloud point, water and sediments, ash sulfates, sulfur, residual coal, acidity index, free glycerin and total glycerin. Regards

I generally agree with the previous comments. However I want to add some clarifications.

You can inject some water in the intake pipe like is done on race cars, the main effect here is to cool down the charge with the goal to increase air density and thus mass flow. You use the latent heat of vaporization instead or in combination with a charge air cooler. The added moisture is fairly low, knocking is reduced mainly by the lower air temperature.

You can also introduce moisture at the engine inlet to the point of saturation. The point here is to use the water's high heat-capacity to lower the combustion temperature, and possibly over-expand the exhaust or recover additional heat. Then one would talk of a Humid Air cycle or Humid Air Motor. I believe this is also practiced in Otto cycle engines (I'd be looking at very large displacement engines), it would also be very knock resistant.

My point being: be sure of what exactly you are asking for.

This can help u

There clearly are harmonic distortions in internal combustion engines - whether diesel or gasoline driven. But the amount of distortions depends on many parameters (eg. number of cylinders, total rotating masses, power request from auxiliary devices (eg. injection pump) and so on).

Thus a generally valid answer about the amount of distortion is impossible. You could start with measuring the 'evenness' of the rotary motion with a high-resolution angular measurement device.

Wish you success

Hi Stephen.

I'l see it. Thank you for the contributio.

Best regards.

I can see here different equations for the laminar and turbulent species module: https://www.sharcnet.ca/Software/Fluent6/html/ug/node602.htm based on this I see no reason not to use it

Nicely explained by prof. Baxter. However,  please see cances et al 2008  fuel 87 (3):274-289 to see mass partitioning of fuel during devolatilization , fate of N and S elements during devolatilization  and char oxidation, fate of C,H and O elements during devolatilization (fig1.8 to 1.11).

I think I have seen BMW's system. Bosch, I believe, is the msnufacturer. In this system the water is sprayed together inside the cylinder with the air and burned fuel at the expulsion cycle. The idea is tompre cool the nect cycle and having a lower temperature one should be able to achieve higher compression ratio  and thus higher efficiency. This system does not mix water with the air- fuel mixture before ignition.

You generally cannot determine the CO/CO2 split from a balanced chemical reaction alone since there will be other fuel-rich species whenever there is CO, and the elemental balances of C H and O are insufficient to determine the amounts of CO, CO2, H2, H2O, O2, N2 and possibly CH4. There are too many unknowns for the number of equations.You probably realize that at peak combustion temperatures, CO2 and H2O decompose to form some CO and H2, even in the presence of O2. Therefore, a simple element balance under fuel-lean conditions (assuming there is no CO or H2 or other fuel-rich species) is not accurate. Furthermore, if you are interested in chemical details, the major radical species O, H, OH, N and CH or soot precursors, such as C2Hx, or pollutants, such as NO, NO2 etc. you are in worse shape still. A chemical equilibrium calculation, which supplements the element balances with thermodynamic equilibrium calculations, is generally sufficient to estimate the major stable species. If you also need radicals, you will need to use a chemical kinetics. 

Dear 

I have the same problem but in a spherical domain (D=25 cm) and in experimental not a modeling 

I am using the fuel LPG-H₂ blend  and this take place only in lean mixture below (Phi=0.6) 

I have already ask a question here in Researchgate.com you can find it and have an answer that the cause in Lewis no. and diffusion issue 

please contact me for vedio or any more details

regards,

 The motored pressure is the pressure cylinder in the absence of combustion. To get it you have to stop the injection and record the cylinder pressure. This pressure is an experimental data.

Estimating the flash point of mixtures is discussed in a NIST paper at http://nist.gov/data/PDFfiles/jpcrd695.pdf. The procedure given here is relatively easy to implement and depends on the components and especially their relative vapor pressures.

You should use the mole fractions that exist at each stage of the reaction. That is, the O2 mole fraction should start at 0.19 and decrease as you step through the reaction. 

If you are trying to use these results in some sort of NOx prediction scheme, you should be aware that the NOx concentration is very sensitive to details of the mixing and turbulent chemical kinetics and very difficult to predict accurately. 

Thank you sir for your response and paper links. 

Yes, you are right. CFD simulations might help to improve the problems associated with the rotary type IC engines. As it is little complicated as compared to reciprocating engine to simulate in CFD, but it is possible with few simplifications.

Thanks,

Parth

it may be increase at high load for following reasons

Air standard efficiency of diesel cycle decreases as the load is increased.

There is simple is that as with increase of load, cut off ratio also increases.

With increase of load more fuel will be injected in combustion chamber.Hence ratio of volume before combustion to volume after combustion will also increase.

i agree.

A bit more details :

Naturally aspirated gasoline engine : between 2 bar (low load)  to 10 bar (full load)

Turbocharged gasoline engine : up to 26 bar (Peugeot EP6 1.6L THP 270ch)

Turbocharged Diesel engine : up to 30 bar (Renault R9M engine 1.6L)

You can calculate it from the torque (T) and the engine displacement (D) by the following formula : BMEP (Pa) = 4*pi*T / D (m3)

DearNahla Afndi,

By understanding the delicate balance of excess air-and-fuel usage,  measure both the concentrations of oxygen and combustibles in the exhaust gas to generate air-to-fuel control strategy. The measurement of both O2 and CO is critical measurements. To maintain the highest combustion efficiency continuously, measurements of both flue gas oxygen and combustibles are required.

When determining the carbon monoxide content from the flue gas we are able to make adjustments to the operation because the CO content represents the unburnt fuel which is wasted because of insufficient air. Alternatively, by measuring the O2 in the stack gas we are able to monitor the loss of energy from too much excess air.

Oxygen and combustible analyzers can provide continuous sampling and analysis of flue gases, making analyzing oxygen and combustibles in the stack gases a way to maximize combustion efficiency. Optimum combustion can be achieved at various air-to-fuel ratios, to correspond with different operating loads. This makes it challenging to use oxygen analyzers alone to control excess air. Additionally, an uneven supply of oxygen in the flue gas could result in oxygen level variations.

What Flue Gas Temperature Tells Us

    Flue gas temperature is an indication of how effectively combustion heat is being transferred to the boiler water.  In general, lower flue gas temperature indicates better heat transfer and higher overall efficiency.  It means that less energy is going up the stack and, everything else being equal, more is going into the water.  If you find flue gas temperature gradually increasing over time, this indicates gradually deteriorating heat transfer within the boiler.  This could be caused by soot buildup on the fire side of the heat transfer surfaces, or scale buildup on the water side.  A flue gas temperature increase of 100°C indicates a boiler efficiency decrease of 4 to 5 per cent.

RECOVER LOSSES WHERE POSSIBLE

    When you are trying to save energy dollars, the first order of business is to reduce energy losses as much as possible.  Sometimes, however, there are unavoidable losses that have some potential for energy recovery.  This makes the second order of business an investigation of energy recovery possibilities.

To Improve Boiler efficiency

1.       To preheat BFW

2.       To Preheat Combustion air

 Flue gas analysis on small combustion systems

 2 gas sensors, which measure oxygen (O2) and carbon monoxide (CO) gases directly, form the basis of the flue gas analysis on small combustion systems such as small furnaces or boilers. flue gas analysers for exhaust gas measurement and flue gas analysis also enable you to measure flue gas loss and CO2concentration on small combustion systems, as well as flue gas temperature, supply air and combustion air temperature, dewpoint temperature, excess air rate and the chimney draught being measured.

Combustion analysis involves the measurement of gas concentrations, temperatures and pressure for boiler tune-ups, emissions checks and safety improvements. Parameters that are commonly examined include: • Oxygen (O2) • Carbon Monoxide (CO) • Carbon Dioxide (CO2) • Exhaust gas temperature • Supplied combustion air temperature • Draft • Nitric Oxide (NO) • Nitrogen Dioxide (NO2) • Sulfur Dioxide (SO2)

Thanks for taking time to answer. Conventionally, there are several systems such as  cyclone, venturi, ESP, bag filters and many other fly ash removal systems available.

However, there are some hot gas clean up systems such as ceramic candle filters, high temperature ESPs available which are expensive and hence not very commonly used. There is a need to find a simpler way to remove ash at the flame stage it self.

Thank you Shubham. 

I will try doing so. I was just wondering if you know any link where I can find the auto ignition temperature of C10H22 at 30 bar pressure ? Because I doubt that my pressure is high as 30bar and temperature is 800K. At this temperature with 30Bar pressure, C10H22 might not get its auto ignition. If you know something about this, please let me know.

Thank you,

Parth

It is my impression that Mr. Pichet is not aiming to measure heat flux at the combustor wall, rather he wants to measure it in the bed (as the combustor wall is most likely to be insulated). The bed has only a small fraction of combustible material, the rest being inert. As the combustion progresses, there is a steady transfer of heat towards the inert material. I presume that this heat flux is what is required to be measured.

In any case, there is serious risk of large errors in measuring heat flux as suggested by Professor Khalil. Unlike measurement of liquid temperature, measurement of surface temperature with thermocouples is always fraught with considerable uncertainties. It also may not be easy to know the composition of the alloy of wall material and the thermal conductivity at the operating temperature of the combustor!

I believe the increased air and fuel in the cylinders of the engine as the gas pedal is pressed results in an increase in engine speed. More air and fuel causes more energy to be released, and thus the engine provides more power to the vehicle, so if the engine has to overcome a similar amount of torque to operate, most of the increased power will go toward speeding up the egine.

We use for our additive mixing tank a pressure relief valve. You can also use a burst disk that is made to break once the inside pressure gets above a certain level.

Hope this helps!

Dear Pankaj Khirade:

SGCR based on the thermolysis of the stoichiometric mixture of metal salts with an organic a substance that acts as a complexing (chelating) agent in the sol-gel process and organic fuel in a combustion reaction. through allocating a large amount of gaseous products generated in conditions of low temperature combustion reaction between the metal nitrates, used as an oxidizing agent, and citric acid, used as a

a chelating agent, a reducing agent and fuel in the reaction system, It formed a very porous, like a sponge, connection

6M(NO3)3 + 5C6H8O7 = 3M2O3 + 30CO2 + 9N2 + 20H2O

chelating agent - organic fuel, reducing agent.

Best regards.

Dear Khaleel

I wish the following articles will be of great help to you.

- Chaichan M T, Combustion and Emissions Characteristics for DI Diesel Engine Run by Partially-Premixed (PPCI) Low Temperature Combustion (LTC) Mode, International Journal of Mechanical Engineering (IIJME), vol. 2, No. 10, pp: 7-16, 2014.

- Chaichan M T, Salam A Q & Abdul-Aziz S A, Impact of EGR on engine performance and emissions for CIE fueled with diesel-ethanol blends, Arabic universities Union Journal, vol. 27, No. 2, 2014.

-Chaichan M T, Abass Q A, Effect of cool and hot EGR on performance of multi-cylinder CIE fueled with blends of diesel and methanol, Al-Nahrain Collage of Engineering Journal, vol. 19, No. 1, pp: 76-85, 2016.

Yes, this works. Consider quasi-static conditions: the engine should run in constant operation for some seconds in every operating point.

kind regards,

Mario

If I remember correctly from courses I took nearly 50 year ago, Fisher's Equation governs both the propagation of a gene through a population and a flame through a combustible mixture.

What do you mean by thermal boundary condition? Actually I was looking for which parameter do I need to change?