# CFD code for supersonic flows

 User Name Remember Me Password
 Register Blogs Members List Search Today's Posts Mark Forums Read

 March 23, 2007, 03:22 CFD code for supersonic flows #1 hedy Guest   Posts: n/a I am working in the field of supersonic fluid dynamics. The main topics contain: 1. the supersonic nozzle design 2. supersonic flows simulation (The important parameters are pressure, velocity, density and so on.) 3. supersonic nozzle optimization Can anybody give me the idea about which code can work well with these topics?

 March 23, 2007, 05:52 Re: CFD code for supersonic flows #2 A.S. Guest   Posts: n/a StarCCM+

 March 29, 2007, 15:44 Re: CFD code for supersonic flows #3 Andy R Guest   Posts: n/a Try Gasp from Aerosft. Note no O in soft! Came out of NASA/Vulcan heritage. Question for A.S - what mach number have you pushed Star-CCC to? My experience with star predates CCM and going much past transonic in V3.X was not too easy. Currently using GASP and FLUENT. We push FLUENT upto about mach 3-4 . GASP we can go as high as 20, but it isn't alll that robust with subsonic flows. My2cents - Andy

 March 30, 2007, 06:22 Re: CFD code for supersonic flows #4 A.S. Guest   Posts: n/a Mach 20 Nozzle

 April 2, 2007, 10:05 Re: CFD code for supersonic flows #5 Bart Prast Guest   Posts: n/a Compressible flow -> use CFX with coupled solver. Will give you an answer in no time. But for for flows beyond Mach 3-4 I would not use the major commercial codes. Use density based codes instead with proper shock handling. You might want to write your own Euler solver (with boundary layer displacement thickness correction). It's fast, cheap and may help you to design your particular nozzle fast. Do this only for relatively simple geometries. Bart

 April 3, 2007, 13:37 Nice site #6 Valintino Guest   Posts: n/a Hello, Your site is great. Regards, Valintino Guxxi

 April 5, 2007, 06:34 Re: Nice site #7 Bart Prast Guest   Posts: n/a Which site? CFD-online?

 April 9, 2007, 11:45 Re: CFD code for supersonic flows #8 Andy R Guest   Posts: n/a AS, Did your Mach20 Nozzle include any chemistry? Temperature dependent properties? What total temp/pressure did you have upstream of the nozzle? Is this a solution you could share? We would be very interested to see a high end commercial code (as opposed to a NASA derivitive product) that can operate in that flow regime. Thanks - Andy R

 April 10, 2007, 15:19 Re: CFD code for supersonic flows #9 EJAZ Guest   Posts: n/a Question: How to choose a time step? Answer: An optimal time step depends on the used mathematical model. General recommendations are as follows: Solid Material: take the time step as one tenth of the body heating time: , where l is the characteristic size of the body, is the coefficient of thermal diffusivity. Laminar Fluid, k-e turbulence model, Weak Compressible Fluid, Combustion Model: take the time step as one tenth of the ratio of the characteristic length of the domain in the steramwise direction to the characteristic flow speed. Free Surface: the time step is determined by the condition that the Courant number equals 1. Full compressible: the time step must provide fast convergence of the pressure calculations. The initial step is specified similarly to Laminar Fluid, k-e turbulence model etc. If the pressure calculations diverge, decrease the time step. If conjugate heat transfer is concerned and a steady solution is sought, different time steps can be defined in the fluid and solid body in order to accelerate convergence to the solution. Select the Use Own Time Step and Step check boxes on the Enthalpy tab in the Method parameters window of the solid sub-region. Enter the CFL number or the global time step in the Step dialog box. Normally, the time step in solid body is higher than that in fluid.

 April 16, 2007, 10:56 CFD code for supersonic nozzle design #10 sandeep Guest   Posts: n/a Can anybody send code for supersonic nozzle design using moc for M 3.5?

 Thread Tools Display Modes Linear Mode

 Posting Rules You may not post new threads You may not post replies You may not post attachments You may not edit your posts BB code is On Smilies are On [IMG] code is On HTML code is OffTrackbacks are On Pingbacks are On Refbacks are On Forum Rules

 Similar Threads Thread Thread Starter Forum Replies Last Post Chris Kleijn Main CFD Forum 0 September 25, 2001 10:17 Chris R. Kleijn Main CFD Forum 16 October 2, 2000 09:15 Patrick Godon Main CFD Forum 32 August 23, 1999 06:55 John C. Chien Main CFD Forum 3 July 12, 1999 09:38 Tareq Al-shaalan Main CFD Forum 10 June 12, 1999 23:27

All times are GMT -4. The time now is 04:15.

 Contact Us - CFD Online - Top