Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

Acusolve transient Heat transfer

Altair Forum User

Hi everyone. I have a quick question regarding the boundary condition in acusolve heat transfer.

image.png.5109c8b64131e83d4ceadceca90adf6c.png

image.png.26c994358eadd36f2778d7c53b8ca1fc.png

This is a transient simulation. Attached is the boundary condition for heat transfer from acusolve

image.png.2410623da003df86bde3401b210000a1.png

I would like to see the efficiency of the cooling channels but when performing the simulation the temperature in the inlet wall is maintaining at 250 C. Is there some way in acusolve to provide that temperature as an initial condition, which means the temperature should not maintain at 250 C throughout the simulation.

As you can see in the below picture the temperature is maintained at 250 C throughout the simulation. I just want it to be an initial condition.

Thanks in advance

<?xml version="1.0" encoding="UTF-8"?>

Find more posts tagged with

AcuSolve

English

Accepted answers

All comments

ydigit

Is this a transient analysis?

you can use the Nodal Initial Conditions to provide this initial temperature. However not in Simple Boundary Conditions.

<?xml version="1.0" encoding="UTF-8"?>

Altair Forum User

Hi ydigit. Thanks for your response.

Yes it is a transient analysis.

As you can see in the below picture I have 2 different temperature profile 250 C and 60 C.

0 image.png.4e1bd221f83bf809876b8f71cb756ea2.png

I'm trying to write script as shown below to specify different temperature to different surface but it is throwing me error.

<?xml version="1.0" encoding="UTF-8"?>

Any help in writing the script is much appreciated .

Thanks

<?xml version="1.0" encoding="UTF-8"?>

acupro

Please describe exactly what you are trying to do with this simulation. Please describe the starting conditions of surfaces and/or volumes, along with what is happening on the outer surfaces of the model - and how things happen in time. Then we can help guide you how to achieve those conditions in AcuSolve.

Altair Forum User

Here is my model, with conformal cooling channels. The inner surface has a initial condition of 250 C and the outer wall has initial condition of 60 C. Need help in providing two different temperature boundary condition which should be zero convection (adiabatic).

Thanks

image.png.6939412a7ce472cc40ff7259896ee3ca.png image.png.2fd1be8bbd1cb23545b4f9539b4922a6.png

acupro

You'll also need to specify the initial temperatures of the volumes, not just the surfaces, in Nodal Initial Conditions. What do you know about the initial temperatures of the volumes - solid(s) and fluid? If you want to perform a time-accurate transient analysis, you need to specify appropriate initial temperatures for all the nodes - volumes/surfaces/etc.

If you want all the outer surfaces to be adiabatic, in Simple BC set temperature type to Flux, and leave all the values at 0.0. This means you're applying no additional heat flux - either specified or through convection coefficient/reference temperature - and since there are no elements on the other side, those surfaces will be adiabatic.

Ovando_RBB

Hi there,

It seems that you are defining the inner and outer temperatures as Dirichlet boundary conditions; that is the reason why those temperatures are never going to change during the transient analysis (they have been hardly imposed).

If you want to capture the temperature evolution starting from a hardly imposed temp. of 250 C in order to capture the cooling curve you will need to define the boundary at 250 C as a natural convection surface (if exposed to atmosphere).

Hope this comment helps!