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autt
29-11-2008, 02:29 PM
Hello everybody,

I have finished the refrigeration system optimization calculation before, then the static refrigeration system simulation with TXV last year, the static refrigeration system simulation with capillary was finished several days ago.

I can't understand how the system equilibrium is reached for a long time. I had searched many articles about static refrigeration system simulation in china but have no answer, some of the articles give the iteration logic but don't tell why, the logic can not be used in my assembled network structure as well.

But finally I have my theory: The key point lies in the refrigerant charging amount. If it is increased, the extra refrigerant will be mainly stored in condenser as liquid, because the gas region holds less weight, the super heat region of evaporator is controlled by TXV, so it's liquid region changes little. If extra refrigerant stays in evaporator the TXV will be closed a little to maintain the evaporator state, then the accumulated refrigerant in condenser cause condense temperature rising to contain more super cooled liquid. The system conditions are different for different charging weight.

System sample with TXV:
http://www.flycarpet.net/en/Ref/images/RefSimLogic_TXV.jpg
parameters change when charging weight changes:
http://www.flycarpet.net/en/Ref/images/RefSim_TXV.jpg

System sample with capillary:
http://www.flycarpet.net/en/Ref/images/RefSimLogic_Cap.jpg

parameters change when charging weight changes:
http://www.flycarpet.net/en/Ref/images/RefSim_cap.jpg

The images are of jpg format, chage the extension name of URL to emf to get the emf format image.

I had thought to give some long term licenses of my software to this forum for everybody for I think it is very useful, now it is possible, the simulation is more understandable so it is easy to use and to check how accurate it is.

Also my software may have many bugs, I have no enough time on it, people here can help me a lot.

So I need to consult how to organize this, moderator please reply.

Thanks and Regards,
Yang

frank
02-12-2008, 09:03 PM
Can't say that I saw the original post, but...... reading on, it would appear that this guy is trying to write some software programme to do with charging refrigerant.

he goes on to say that it contains some bugs.....
enough said.

I get the feeling that he is asking for help with his Beta programme.

autt
03-12-2008, 03:16 PM
Can't say that I saw the original post, but...... reading on, it would appear that this guy is trying to write some software programme to do with charging refrigerant.

he goes on to say that it contains some bugs.....
enough said.

I get the feeling that he is asking for help with his Beta programme.


Can you help to tell what's wrong with this post?

autt
03-12-2008, 04:17 PM
Is that clear about these images?

Explanation:

SCHEME:
Data group on top of lines in sequence:
Refrigerant flow, kg/s
Refrigerant pressure, Pa
Refrigerant temperatuer, deg
Refrigerant pressure for purpose of iteration, Pa

Data into RefrigerantBalancer:
Refrigerant capacity of each accessories, kg

Data out of RefrigerantBalancer:
Iteration coefficient to adjust compressor output pressure, relative to extra total charging quantity, this is the key algorithm about the system balance. Anybody wants to simulate/model the refrigeration system can try this method.

CURVE:
RefrigerantBalancer_MC: Charging Quantity, kg
Compressor_W2: Compressor output refrigerant flow, kg/s
Condenser_TK: Condense temperature, deg
Evaporator_TE: Evaporate temperatuer, deg
Evaporator_HT: System cooling capacity, W
Condenser_TSC: Condenser super cooling temperature at outlet, deg
Evaporator_TSH: Evaporator super heating temperature at outlet, deg

From these calculation results, when charging quantity increase:
Compressor output refrigerant flow may decrease slightly for TXV system;
Compressor output refrigerant flow may increase slightly for Capillary system;
Condense temperature will increase;
Evaporate temperatuer may decrease slightly for TXV system;
Evaporate temperatuer may increase slightly for Capillary system;
System cooling capacity may increasae for TXV system;
System cooling capacity has maximam point for capillary system;

Sorry for my chaos brain, is that clear enough? Anyone who has different results/ideas please talk about.

Regards,
autt

Brian_UK
03-12-2008, 07:34 PM
What is it that you want from us?

You don't seem to have asked a question yet.

It seems that you want somebody to Beta test your software, is that correct?

autt
04-12-2008, 07:39 AM
What is it that you want from us?

You don't seem to have asked a question yet.

It seems that you want somebody to Beta test your software, is that correct?

I want to contribute some license of my software for this forum, anybody here can use, test, remark it, discuss the algorithm of refrigeration system simulation and optimization, and so on.

I had thought about this before but seems hard to operate for the site, so I want to ask if this can be adopted here? I am not clear about the organization of this site, I don't know whom I need to ask, I have contacted the webmster and is waiting for reply.

If not, I will find someone to help test.

Still, any discuss such as about the algorithm and results would be appreciated.

Thanks

Brian_UK
05-12-2008, 12:07 AM
Why do you want to use this forum to beta test your commercial software?

Why not employ beta testers yourself.

autt
05-12-2008, 02:59 PM
Hi Brian_UK,

I prepare to make it to be a commercial software for several years, but I haven't found any cooperator who has interest to invest it, I myself do't have enough money for complete test as robot and accurate, and running cost of a company. I had sent tens of keys but no any message returns.

Now I am still in work, time for the program is not enough, it is still stay in my personal disk. Our department was moved to a institute owned company without our consent, new policy is strict and income is much reduced, the future may or must be worse because of passive resistance. Some people in our company and some others in the institute applied for resign to change to another institute without permitted, this may put in suits but few chance to win, now it was said the government has taken this matter. With gray future I am struggled to find a way out.

No matter if my idea looks stupid here, I can find other way.

Thank you for reply.
autt