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Supersonic flow

Posted 23.07.2012, 15:11 GMT-4 1 Reply

Jhon Freddy Alfonso Serrano
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I´ve a problem when I try to simulate a basic nozzle inducing supersonic flow in hmnf. I define a subsonic inlet (Mach number/ high pressure) and an outlet (pressure or supersonic condition). Trying to solve the model, i've encountered with a problem that I don´t understand; the message is:

Failed to find a solution.
Segregated group 1

Singular matrix.

There are 33 void equations (empty rows in matrix) for the variable mod1.hmnf.TWall.
at coordinates: (-32.0383,580.87), (-33.1644,583.411), (-34.5208,585.837), (-70,600), (-36.0958,588.127), ...
and similarly for the degrees of freedom (empty columns in matrix).
Returned solution is not converged.

My question is. ¿What´s the meaning of "mod1.hmnf.TWall?¿How I define it in High Mach Number Flow?

Thanks.
1 Reply Last Post 04.09.2012, 08:25 GMT-4
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Hello Jhon Freddy Alfonso Serrano

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Friedrich Baumann
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Posted: 1 decade ago 04.09.2012, 08:25 GMT-4
Hi,

you can't find "mod1.hmnf.TWall since you haven't a solution. I was wondering too. I think you have a problem with your initial values and boundary-conditions. Or there is a sharp edge or point in your geometry you should supress before meshing.

I suppose it stopped in iteration no 1?

Bye
Hi, you can't find "mod1.hmnf.TWall since you haven't a solution. I was wondering too. I think you have a problem with your initial values and boundary-conditions. Or there is a sharp edge or point in your geometry you should supress before meshing. I suppose it stopped in iteration no 1? Bye

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