# Approximated Compressor Map by empirical Coefficients - basic compressor in a moist air network (Aircraft Environmental Crontol System)

조회 수: 3(최근 30일)
David Reimert 2021년 5월 4일
댓글: David Reimert 2021년 6월 15일
In order to simulate a compressor in a moist air network I found the custom component of a basic compressor in the Aircraft Environmental Crontol System - Example provided by MathWorks.
You can open ssc_aircraft_ecs to see the compressor block with the parameters.
I have a compressor map of the compressor I want to simulate in the model. In the basic compressor block the compressor map is approximated by empirical coefficients that control the shape of the speed lines and scaled based on a known nominal operating condition.
The parameters are
• Coefficient for curve through the bend of the speed lines (default 1.5)
• Coefficient for spacing of speed lines (default 0.7)
• Coefficient for sharpness of the bend of the speed lines (default 0.08)
My question is: How to determine the 3 coefficients with the compressor map?
I couldn't find an answer to my probem. I hope you can help me.
Best regards
David
##### 댓글 수: 1표시숨기기 없음
Yifeng Tang 2021년 5월 6일
Couple things to try:
1. Item 4 in this example allows you to plot the compressor map for the given coefficients. In the actual code, you can see the equations that are using these coefficients. This may allow you to use tools like curve fitting toolboxes to get these coefficients from your map.
2. set up a testing harness around the compressor, using controlled reservoirs. Perform a parameter estimation exercise (Documentation: https://www.mathworks.com/help/sldo/parameter-estimation.html). This requires Simulink Design Optimization. More general info on this topic: https://www.mathworks.com/discovery/parameter-estimation.html
If you don't have access to the toolboxes mentioned, you can always use the sample code from the demo and compare the compressor map manually (ouch)

댓글을 달려면 로그인하십시오.

### 채택된 답변

Yifeng Tang 2021년 6월 14일
Couple things to try:
1. Item 4 in this example allows you to plot the compressor map for the given coefficients. In the actual code, you can see the equations that are using these coefficients. This may allow you to use tools like curve fitting toolboxes to get these coefficients from your map.
2. set up a testing harness around the compressor, using controlled reservoirs. Perform a parameter estimation exercise (Documentation: https://www.mathworks.com/help/sldo/parameter-estimation.html). This requires Simulink Design Optimization. More general info on this topic: https://www.mathworks.com/discovery/parameter-estimation.html
If you don't have access to the toolboxes mentioned, you can always use the sample code from the demo and compare the compressor map manually (ouch)
##### 댓글 수: 1표시숨기기 없음
David Reimert 2021년 6월 15일
Than you!! I've chosen the Parameter Estimation. Powerful tool and easy to use.

댓글을 달려면 로그인하십시오.

R2020b

### Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by