I am studying in a direct expasnion system in pneumatic library. It's a simaple system but I still got some problems in that.
First, I used a single srcoll turbine as the expander but I can't understand the parameters in that unit.
Second, I can't make the rotation speed started from 0 to a curtain RPM so that it can't be a dynamic system.
Cqn you guys please give me some idea of that? Thank you very much!
I'm afraid I don't know much about turbines/compressors but I think that the turbine maps should drive most of the model's behaviour. If there is a doubt about the parameters, the help of the component is here to provide some information.
With your model, I noticed that if the inertia of the turbine shaft is initialized with a high enough negative rotary speed (-2000 rpm for example), it will then start to react to pressure changes. The default map has a restricted operation range and it will often get off the map. Below the corrected mass flow rate map is loaded from a blank plot and the current turbine operation point (speed, mass flow, pressure ratio) is overlayed to see where we are compared to that map.
Ideally the maps used in the turbine should correspond to your use case. In the model above, I changed the pipe diameter to 50 mm to allow for more mass flow and inlet pressure is 10 barA.
Thank you for your reply.
I actually checked the data file for this turbine's characteristics. I noticed that the corrected mass flow rate matched with Pressure Ratio and rotation speed is in the range of 1-10kg/s. It's much higher than my design. If I only aim to control the mass flow in a small valve like 20g/s, in which way I can realize that?