With the specified level of detail it is absolutely impossible to answer this question or to give any advice.

If you should expect, that some CFD expert is spending the time to read your question, think about it and to finally provide some advice, then you should be so kind as well, to spend the affordable time to describe your issue to an extend, that it is understandable to others - what domain, which boundary conditions applied, which equations solved and last but not least what the hell of a solver system (out of the 100+ different possibilities of existing CFD solvers worldwide) are you trying to use?

Science is to a substantial extent depending on proper communication. Now it is your turn to communicate your issue properly, comprehensively and to a more substantial degree of completeness.

Regards,

Dr. Th. Frank.

My sincere apologise Sir,

I am actually new to this. So i don't know what to mention and all. Hope you will understand

Density based solver with fluid as air (ideal gas density and sutherland function for viscosity)

Turbulence model - SST K-omega

Pressure farfield as freestream with mach 6 and pressure 1064 pa and temperature 234 K

I have used the same as reference values too.

Flux type - ROE FDS

Green gauss node based discretisation scheme

CFL number 0.5

Please let me know if anyelse information is needed.

Still not knowing, which solver you are trying to use. From mentioning the density-based solver, I can only guess it's ANSYS Fluent.

The question is: heat transfer rate to WHAT? Energy equation is getting solved? What are the defined and applied thermal boundary conditions (to a solid boundary of a bluffed body or something, where you are curious about the heat transfer rate)? Or is this flow simulation setup to be isothermal?

Regards,

Dr. Th. Frank.

Solver - 2Ddp implicit density based solver

RANS equations are solved

I am doing this analysis over Orion based CEV(bluff body)

Actually i need to get the heat flux over the surface of the vehicle inorder to estimate the aerodynamic heating over it

So could you suggest me what might be the thermal boundary conditions i need to provide inorder to obtain this heatflux over the surface.

You need to activate in Fluent (!) the energy equation.

Further you can specify different alternative kinds of thermal boundary conditions, depending on your physics:

1) fixed (known) surface temperature

2) fixed (known) heat flux

3) fixed (known) heat transfer coefficient

4) A prescribed heat source or heat sink inside the solid body. This would require to mesh the interior of the solid body and to solve an energy equation in the solid. This is also known as a conjugate heat transfer (CHT) problem. Same would apply, if you would be interested in the transient heating of the solid material over time due to the aerodynamic heating and starting with a prescribed initial body temperature.

But essentially I cannot know, what kind of physical conditions you intend to simulate.

Regards,

Dr. Th. Frank.

Thanks a lot Dr. Th. Frank

But I am doing 2d axissymetric analysis.

As I need to calculate the heat flux variation over the surface i can't give a fixed value for it.

So then, do i have to give heat transfer coefficient?

Also if possible could you please tell me what could be the reference area for calculation of Cd incase of 2d axissymetric solving