Aerospike flow 3rd order

dim_slo · April 5, 2011, 22:22

I have a few questions concerning a 1st and 3rd order 'solution'. Below is a pic of my grid (~2.2 million):

I first wanted to solve for a 1st order solution with a pressure inlet and pressure outlet and laminar turb as a simple starting point. My question about the 1st order solution is about the convergence. Is is typical for the 'other' velocities to not converge to a low value like shown in the pic below? Even the other values converge to only ~10-2:

Here is a pic of the mach contour:

The residuals didn't converge to a low number but the flow looks right and the mass flux balances correctly.

dim_slo · April 5, 2011, 22:25

When I use the first order case to start the 3rd order solution (3rd order MUSCL), the flow becomes unstable at the outlet boundary, is this typical of a higher order solution (problems near the boundary)?

Can anyone help me out with what I'm doing wrong?

April 5, 2011, 22:22	Aerospike flow 3rd order	#1
dim_slo New Member Join Date: Apr 2011 Posts: 5 Rep Power: 15	I have a few questions concerning a 1st and 3rd order 'solution'. Below is a pic of my grid (~2.2 million): I first wanted to solve for a 1st order solution with a pressure inlet and pressure outlet and laminar turb as a simple starting point. My question about the 1st order solution is about the convergence. Is is typical for the 'other' velocities to not converge to a low value like shown in the pic below? Even the other values converge to only ~10-2: Here is a pic of the mach contour: The residuals didn't converge to a low number but the flow looks right and the mass flux balances correctly.

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April 5, 2011, 22:25		#2
dim_slo New Member Join Date: Apr 2011 Posts: 5 Rep Power: 15	When I use the first order case to start the 3rd order solution (3rd order MUSCL), the flow becomes unstable at the outlet boundary, is this typical of a higher order solution (problems near the boundary)? Can anyone help me out with what I'm doing wrong?