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U-slip is used to calculate the drag coefficient in EMMS/bubbling model. But there are three different slip velocities in the model. I do not know which one should be chosen here. And my calculation results are a little bit different from the references.
The references I used are as follow:
[1]HONG K, SHI Z, WANG W, et al. A structure-dependent multi-fluid model (SFM) for heterogeneous gas–solid flow [J]. Chemical Engineering Science, 2013, 99: 191-202.
[2]SHI Z, WANG W, LI J. A bubble-based EMMS model for gas–solid bubbling fluidization [J]. Chemical Engineering Science, 2011, 66(22): 5541-55.
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According to one of the authors of this model, the U-slip used in this model equals the superficial gas velocity at the gas inlet of the fluidized bed.
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I am a Professor of a university which is having its campuses in different parts of the globe and there are many professors in different fields. We are all taking various faculty development programmes across different domains of Engineering, science. Most of this technical certifications are of very high order. However with research and teaching being part of our curriculum I would like to ask you to suggest a few online course which can be done for ABET and other accreditation and useful for the education industry point of work since I have to continue my work as a professor and it will involve gradation also.
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From what I understand you need suggestions on short training courses, I think if what matters is building a global academic view, you should aim at training in public policies and delve into educational ones.
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Dear all,
I have submitted the manuscript in Journal of Engineering Science and Technology Review (JESTR) since 10 months ago.
I have tried to send email to the editor many times, but there is no any responses.
Therefore, I would like to withdraw my manuscript since I am not sure whether the journal is still active or not.
The submission system is a bit poor, there is no option to withdraw the manuscript .
Could any one give please me an advise about this situation?
Thank you,
KM
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I submitted a paper to the same journal in June 2020. Till now there is no response from the journal. I emailed the editor several times and there is no response.
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In Engineering, Science, and Fluid Dynamics, there are many unitless numbers very useful for effective simulation. However, is there any parameter you analyze recently and you just appreciate your observation?
Which dimensionless parameter have you analyzed and deeply appreciate it's significance?
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The Reynolds number (Re) helps predict flow patterns in different fluid flow situations.
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Hi Everyone. Please suggest me the SCI journals list which don't contains article processing charges.
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Dear Srinivas Talasila, you can check here to find out your desired SCI Journal without APC: https://www.letpub.com/index.php?page=journalapp
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Greeting to all.
Drear researcher,
I am working with the conference organizing committee as publication head. It is a multidisciplinary conference on Engineering, Science, and Humanity. How and what is the best way to collaborate with Scopus indexed journals in different areas. I need your assistance.
Thanks in Advance
Best Regards.
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European countries produce frequently research based PhDs, in Germany they call it Dr-Ing. for example. I am looking for Universities in US who are doing similar in STEM area, i.e. capable to produce Doctor of Engineering, it's DEng, or DSc (Engineering or Science) or similar. MIT has prestigious DSc for example.
Thanks, Teddy Ivanitzki
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I'm sorry I can not answer this question
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A lot people in
Computer Science
Management Science
Engineering Sciences
are leaving Pakistan and moving abroad?
What are main reasons and is the same happening in INDIA, BANGLADESH etc
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Why science, technology, and engineering? Because those are the fields in which there is demand, ease of access, and mobility, unlike the situation for people with softer skills or for professionals in certain fields (e.g. medicine) in which their credentials aren't accepted at face value and they must go through longish retraining/recertification periods. The folks I know who left from Pakistan and the Middle East were more concerned about stability and freedom and a better life for their children than excessive materialism; they lead modest lifestyles and their desires for comfort and a material safety net are quite middling.
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Our journal (International Journal of BIM and Engineering Science) publish by BIMarabia. Just have one volume and one issue. We want to rapidly get top ranked and high impact factor. Kindly please, your advice to achieve this goal.
Someone advised me that we should have much indexing. Kindly please, can you advise us how can we get index in the most important sites to achieve our goal as soon as possible.
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It is not so easy as you think. Citation impact is one of the defining characteristics of journals to be awarded with Journal Impact Factor. Similar yardstick is followed for CiteScore too. In any case, a minimum there years is necessary to calculate Impact Factor ( for CiteScore, four years). If you want high rank or high impact for your journal, from the beginning itself concentrate to maintain quality. If you publish original papers with novel ideas, other researchers will cite your findings. Please read journal selection process for awarding Impact Factor from the link: https://clarivate.com/essays/journal-selection-process/
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Hello,
I am looking for suggestions how to improve and better evaluate a nonlinear regression model for the differential equation of the reaction rates of DME Synthesis. This are the main results ( more information on the set-up below):
The results indicate that all kinetik Arrhenius factors kTr tend towards zero, as well as the Adsorption constants K_tr,CO2 and H2 and deltaH_ads,CO.
The confidence intervals for the Adsorption coefficients and enthalpy of CO2 and H2 are extremely large and include zero, leading to a lack of statistical significance. T
he Parameter Covariance Matrix suggests correalation between kMeOH and K_trCO, kMeOH and K_trH2, k3 and activation Energy E_an_WGS, E_anMeOH and H_adsCO and -CO2, as well as between the Adsorption constants K_trCO and K_trH2 and ads. enthalpies H_adsCO and H2.
I therefore wanted to ask:
  • Is there any statistical interference /hypothesis tests, similar to the F-test for a complete linear regression model, which I could use for reparametrization?
  • How would you check for colinearity between the parameters?
  • You know of any methods for detecting outliers in the data-set for non-linear regression?
  • Is there any toolbox / open-source code or literature in Matlab for implementing bayesian regression techniques for ODE models?
  • You think the matlab function nlparci is a good tool for calculating confidence intervals for such a model?
  • Any other suggestions for improving / testing the model
  • I was thinking therefore of somehow replacing the adsorption constants by one general term for all three, but I dont have a concrete idea yet. I was also surprisded that the Arrhenius factors tend towards zero.
  • Perhaps I should also remodel the Temperature dependency of the Arrhenius factor
  • Would you consider trying a Bayesian regression approach in order to reduce the number of parameters?
Setup:
I am considering experimental data a collegue has made based on the following DME network:
CO2 + 3H2 <-->CH3OH + H2O MeOH
2CH3OH <--> CH3OCH3 + H2O DME
CO + H2O <--> CO2 + H2 WGS
She has fitted parameters for the results of catalyzed fulid bed reactor with the reaction rate model of Lu (Simulation and experiment study of dimethyl ether synthesis from syngas in a
uidized-bed reactor. Chemical Engineering Science) 59(22-23):5455{5464, 2004).
The reaction rates contain an Arrhenius factor ki, Fugacities, Equilibrium Constant Kfi in terms of pressure and the Adsorption constant Ksubstance. The equations are are in the appendix.
She had approximately 240 experiments varying in inlet concentration, Temperature and volume flow. The estimation was done with matlab lsqnonlin, solving a basic PFR Model with the Ordinary Differential equation
dy/dz = RTZ / (up) * (-y sum_komponent_reaction(stochiometric koef.*r_reaction) + sum_reaction(stochiometric koef*r_reaction).
Best,
Dennis
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I suspect the rate limiting step is not really a 4 molecule collision between CO2 and 3 H2 molecules like the rate expression implies. and the water gas shift reaction (CO + H2O <=> H2+ CO2) probably also should be included in the mechanism (most likely goes to equilibrium).
Since the reaction is usually equilibrium limited I would suggest a rate equation numerator with the form K(PH2-H2eq)^a(PCO-COeq)^b. 1 (or 0) is probably a good starting value for a and/or b.
2/3 power Langmuir inhibition by adsorption of H2 also seems a bit unusual. I also prefer partial pressures instead of fugacity in rate constants expressions but it probably doesn't make much difference.
I would try a very simple fit without the denominator for the first pass R = K(PCO-PCOeq) then R = K (PH2 - PH2eq) as a first pass then step by step include both CO and H2 in the numerator then add the denominator to see if it improves the fit. There will probably be a trade off between lowering numerator exponents and raising denominator Ks that will give approximately equivalent data fits.
Don't expect that regression to fit every constant all at once and repeat the regression from very different starting points to see if you can converge to the same answer.
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There are many types of chaotic maps and we want to study relationship between them. Our aim is to find which type implies the other or in other word, which one is stronger than the other.For hint: see New Concepts of Alpha-Chaotic Maps - Journal of Multidisciplinary Engineering Science and Technology (JMEST)
ISSN: 3159-0040 - Vol. 2 Issue 2, February - 2015 
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I'm trying to validate the method of calculation of exergy. I would like to compare the results of my calculations with example from Hinderink, A. P., F. P. J. M. Kerkhof, A. B. K. Lie, J. De Swaan Arons, and H. J. Van Der Kooi. “Exergy Analysis with a Flowsheeting simulator—I. Theory; Calculating Exergies of Material Streams.” Chemical Engineering Science 51, no. 20 (October 1996): 4693–4700. doi:10.1016/0009-2509(96)00220-5.
Which is  interesting because the stream is gaseous in actual and mixed phase in reference conditions.
I used simulator to calculate enthalpy and exergy in actual and reference conditions. Below are the values from simulator. Actual conditions are 150degC, 101325Pa and composition as below. Reference conditions 25degC, 101325 Pa 
Stream Actual conditions Reference conditions
kmol/s Mol Frac kmol/s Mol Frac
Water 0,22 0,22 0,22 0,22
Carbon Dioxide 0,02 0,02 0,02 0,02
Carbon Monoxide 0,01 0,01 0,01 0,01
Nitrogen 0,75 0,75 0,75 0,75
Nitric Oxide 0,01 0,01 0,01 0,01
** Total Flow 1,00 1,00
Frac Vapor 1,00 0,81
Molec Wt 26,14 26,14
Temperature Kelvin 423,15 298,15
Pressure Pa 101325,00 101325,00
Mass Flow kg/s 26,14 26,14
Enthalpy J/kmol 3801830,20 -8568429,40
Entropy J/kmol-K 16301,26 -26524,05
So first column are actual conditions of gas, and second column are reference conditions:
I calculate: 
Ex_ph = h-h0 - T0*(s-s0) and i get the result Ex_ph = -398kW
which is completely different than mentioned source, which claims the Ex_ph to be 2532kW.
What is wrong with my calculation? Or maybe something is wrong with enthalpy or entropy of the stream?
Regards,
Marcin
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Perhaps because of this mistake is the neglect of the enthalpy or entropy
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Hi Im trying to combine Actuator disk theory with CFD.
I found two options
Either to add source term to momentum equation or use pressure jump boundary condition. (fan boundary).
Can anyone explain me of this
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Fan boudary is simple to use, and you can describe the pressure jump distribution using a polynomial. Remember that for a wind turbine the pressure jump is negative.
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Literatures suggest that positive polarity is commonly used for Macro level EDM process and negative polarity for micro EDM.
What is the basic reason behind this?
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My first problem is the term positive polarity, because it does nit indicate which electrode is positive or anodic. Examinating the removals of he anode and the cathode, then we find that the anodic removal for time ranges up to about 1 µs is substantially larger than the cathodic removal. For most metals this turning point (anodic and cathodic removal is equal) between 0.8 and 2 µs. For WC-Co-alloys at this point is 20 µs and higher. WC-Co alloys are therefore machined with anodic workpiece polarity reversal.
The differences between EDM and Micro-EDM are the micromachining is performed exclusively with needle pulses under 2 µs. The same statement applies to the Wire-EDM to.
Therefore, it is incomprehensible to me when working in Papers in Wire-EDM with pulse duration greather than 100 µs. (????)
In the final analysis thus depends on the chosen polarity of processing of the used process energy source (generator).
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when I clicked the run button, the system shows
The matrix is not strictly diagonally dominant at row 1
The matrix is not strictly diagonally dominant at row 2
The matrix is not strictly diagonally dominant at row 3
The matrix is not strictly diagonally dominant at row 4
What dose this mean?? what's the matter with my input??
clear;clc
format compact
%% Read or Input any square Matrix
A = [-8.7673 9.4736 0 0 0;
4.7368 -8.4736 4.7368 0 0;
0 4.7368 -8.4736 4.7368 0;
0 0 4.7368 -8.4736 4.7368;
0 0 0 -9.4736 10.4736];% coefficients matrix
C = [20;20;20;20;20];% constants vector
n = length(C);
X = zeros(n,1);
Error_eval = ones(n,1);
%% Check if the matrix A is diagonally dominant
for i = 1:n
j = 1:n;
j(i) = [];
B = abs(A(i,j));
Check(i) = abs(A(i,i)) - sum(B); % Is the diagonal value greater than the remaining row values combined?
if Check(i) < 0
fprintf('The matrix is not strictly diagonally dominant at row %2i\n\n',i)
end
end
%% Start the Iterative method
iteration = 0;
while max(Error_eval) > 0.001
iteration = iteration + 1;
Z = X; % save current values to calculate error later
for i = 1:n
j = 1:n; % define an array of the coefficients' elements
j(i) = []; % eliminate the unknow's coefficient from the remaining coefficients
Xtemp = X; % copy the unknows to a new variable
Xtemp(i) = []; % eliminate the unknown under question from the set of values
X(i) = (C(i) - sum(A(i,j) * Xtemp)) / A(i,i);
end
Xsolution(:,iteration) = X;
Error_eval = sqrt((X - Z).^2);
end
%% Display Results
GaussSeidelTable = [1:iteration;Xsolution]'
MaTrIx = [A X C]
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Hi Maria. As far as I got it without running the code, there is one error at
Check(i) = abs(A(i,i)) - sum(B);
which should rather read
for i=1:n
Check(i) = abs(A(i,i)) - sum(abs(A(i,:)));
if Check(i) < 0
fprintf('The matrix is not strictly diagonally dominant at row %2i\n\n',i)
end
or something like that, since diagonal dominance states that absolute values of diagonal elements are always greater or equal to the absolute values of the other remaining (absolute) row elements.
Moreover, it seems to me that the input matrix A in your example is not diagonal dominant, as e.g. |A(1,1)|<|A(2,1)|.