UDF_unsteady
 

Dear Sir

I am doing unsteady analysis of nozzle, pressure at inlet is varying from 10 bar to 1 bar from 0 to 2 sec.

I wrote udf's for total pressure and supersonic/ initial gauge pressure at inlet. But fluent define only one udf at a time.

when i define second udf, firstly define udf was disappeare from the memory.

How can I define time verying profile of total pressure and supersonic/ initial gauge pressure at inlet?

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For an unsteady problem, at a point in flow domain, I am looking to draw plot of a property (mach number , velocity etc.) vs time.

Is it possible to draw plots of properties vs time? If possible, please guide me.

Thanks & Regards

Re: UDF_unsteady
 

hi,

Just create a point surface of the precise location you want to monitor by exploring surface/point. Once this surface is created, create a monitor of the quantity you wish to monitor under solve/monitors.

Unless you to monitor some special quantity not available in Fluent, you do not need a UDF for this.

Hope this helps David

Re: UDF_unsteady
 

You have to put all your UDFs into one file.

Re: UDF_unsteady
 

thanks its working

Re: UDF_unsteady
 

Its working, thanks.

I am doing analysis of a nozzle , solution is going to converge at inlet pressure 45 bar & outlet pressure 1 bar, but it is going to divarge when i am imposing inlet pressure around 5 bar.

for same geometry and same boundary condition why its happening? I think flow physics become so complex, so fluent diverge.

May yoy help that how can I get a converge solution at low pressure inlet?

Re: UDF_unsteady
 

Thanks its working.

I am doing analysis of a nozzle , solution is going to converge at inlet pressure 45 bar & outlet pressure 1 bar, but it is going to divarge when i am imposing inlet pressure around 5 bar.

for same geometry and same boundary condition why its happening? I think flow physics become so complex, so fluent diverge.

May you help that how can I get a converge solution at low pressure inlet?