Changing flow Mach No. by changing Pressure Outlet in Pressure driven supersonic flow

Goel · June 20, 2021, 18:09

I am simulating the supersonic flow inside a wind tunnel section with top and bottom as walls (Boundary condition). In this, the flow is pressure-driven with high inlet pressure to low pressure at outlet.
I use pressure inlet BC at inlet and pressure outlet with 0 static pressure at outlet. Then after 1st result I raised the outlet temperature but there is no change in flow noticed.

LuckyTran · June 21, 2021, 17:53

The outlet temperature is not invoked unless there is reversed flow, and there shouldn't be any reversed flow in a wind tunnel. That's why changing the outlet temperature does nothing.

Goel · June 22, 2021, 05:48

So how can I vary the flow Mach No. from the initial 2.5 to ultimately stopping the flow?

June 20, 2021, 18:09	Changing flow Mach No. by changing Pressure Outlet in Pressure driven supersonic flow	#1
Goel New Member Priyank Goel Join Date: Jun 2021 Posts: 3 Rep Power: 5	I am simulating the supersonic flow inside a wind tunnel section with top and bottom as walls (Boundary condition). In this, the flow is pressure-driven with high inlet pressure to low pressure at outlet. I use pressure inlet BC at inlet and pressure outlet with 0 static pressure at outlet. Then after 1st result I raised the outlet temperature but there is no change in flow noticed.

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June 21, 2021, 17:53		#2
LuckyTran Senior Member Lucky Join Date: Apr 2011 Location: Orlando, FL USA Posts: 5,754 Rep Power: 66	The outlet temperature is not invoked unless there is reversed flow, and there shouldn't be any reversed flow in a wind tunnel. That's why changing the outlet temperature does nothing.

June 22, 2021, 05:48		#3
Goel New Member Priyank Goel Join Date: Jun 2021 Posts: 3 Rep Power: 5	So how can I vary the flow Mach No. from the initial 2.5 to ultimately stopping the flow?