Effacer les filtres
Effacer les filtres

Why the volumic flow rate sensor (motion air) is registering a negative value?

3 vues (au cours des 30 derniers jours)
Karl Schaan
Karl Schaan le 3 Sep 2021
I'm trying to modeling a Environmental Control System (ECS), where a DC Motor drive a Turbine (HVAC library). To do so I am using a 2-Port Constant Volume Chamber (MA). However, the Volumic Flow Rate Sensor (MA) is registering a negative value. The Pressure is 1.103 atm and the Temparture is 20 °C in the moist air network.
Is there a better way to model an ECS with the available Simscape resources? I have also tried to use the Rotational Mechanical Converter (MA) but it's the same problem.
I have attached the model.
Thanks in advance for any help.

Réponses (1)

Yifeng Tang
Yifeng Tang le 29 Juil 2022
As @VBBV mentioned in the comment, switching the A/B port is likely the solution.
Is this turbine block the same one as in theAircraft Environment Control System demo? If so, the flow is expect to flow into the A port when the R port has a positive rotation. I'm a bit confused by the A port of the turbine connected to "Out air" though. When air flows into the A port of the turbine, it's flow from the B port of the flow sensor to the A port. By the definition of the sign in this sensor, it's negative flow. In the documentation, it states: The relative orientation of ports A and B establishes the measurement sign. The sign is positive if flow occurs from port A to port B. Switching port connections reverses the measurement sign.


En savoir plus sur Foundation and Custom Domains dans Help Center et File Exchange




Community Treasure Hunt

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

Start Hunting!

Translated by