[kimie]

Originally Posted by ghorrocks

I do not understand your graph. Please label the axes and label the curves. Is it the load or the turbine?

The load curve should increase with speed and the turbine curve should decrease with speed.

hye ghorrocks!

this is my latest update for my chart.

torque rpm.png


seem like both of the curve is accending but i need to run more point to see what happen at a little higher rpm.

all of this happen because of your help.i really want to thanks you alot.

[ghorrocks]

It is unusual for a turbine to be operating in a regime where its torque increases with speed. This suggests it is operating a long way from its design condition, which probably means big separations and other nasty things.

This may be intentional - if so then please continue. But be aware that this system is not running at optimal conditions.

[kimie]

Originally Posted by ghorrocks

It is unusual for a turbine to be operating in a regime where its torque increases with speed. This suggests it is operating a long way from its design condition, which probably means big separations and other nasty things.

This may be intentional - if so then please continue. But be aware that this system is not running at optimal conditions.

I think I may get this kind of graph because I am using load by using direct formula which is 2*pai*torq*speed/60


Maybe I should using isentropic load ?

[kimie]

Ghorrocks I have just realize that my inlet pressure has drop too much with my added wastegate and my outlet pressure has become a negative value..I am so sad with my problem..thanks you for helping me so much..

[kimie]

Now i am trying to run the simulation with the outlet boundary instead of opening boundary. I try to set up my waste gate mass flow rate outlet to 1% of the inlet mass flow rate at 30000 rpm .maybe I can see something from there. The wastegate area also has been decrease to see whether it can influence the result.

[ghorrocks]

I think I may get this kind of graph because I am using load by using direct formula which is 2*pai*torq*speed/60

My post #22 says the TURBINE torque should decrease with increasing speed. Your reply is talking about the load.

[kimie]

I am so sorry for my reply ghorrocks.Maybe I should try my simulation with a smaller wastegate area. I guess my current area is too big for the turbine design condition.

Thanks ghorrocks for your reply. I really appreciate every knowledge you share .