How ANSYS treats thermal modelling

October 9, 2018 learnwordx33

Only the ANSYS/multiphysic, ANSYS/Mechanical, ANSYS / Thermal and ANSYS / FLOTRAN programs support thermal analysis. The basis for thermal analysis in ANSYS is a heat balance equation you perform via ANSYS calculates nodal temperatures and then uses the nodal temperatures to obtain other thermal quantities. The ANSYS program handles all three primary modes of heat transfer: Conduction, Convection, and radiation.

Convection

You specify convection as a surface load on conducting solid elements or shell elements. You specify the convection film coefficient and the bulk fluid temperature at a surface; ANSYS the calculates the appropriate heat transfer across that surface. If the film coefficient depends upon temperature, you specify a table of temperatures along with the corresponding values of film coefficient at each temperature.

For use in finite element models with conducting bar elements (which do not allow a convection surface load), or in cases where the bulk fluid temperature is not known in advance, ANSYS offers a convection elements named LINK 34.In addition, you can use the FLOTRAN CFD elements to simulate details of the convection process, such as fluid velocities, local values of film coefficient and heat flux, and temperature distributions in both fluid, and temperature distributions in both fluid and solid regions.

Radiation

ANSYS can solve radiation problems, which are nonlinear, in four ways:

By using the radiation link element, LINK 31

By using surface effect elements with the radiation option (SURF 151 in 2-D modelling of SURF 152 in 3-D modelling)

By generating a radiation matrix in AUX 12 and using it as super element in a thermal analysis.

By using the raisosity solver method,.