26.17.4 Checking Material Properties

Figure 26.17.6: The Materials Tab in the Case Check Dialog Box

The following recommendations appear under the Materials tab (Figure  26.17.6):

• Assign individual fluid Cps to polynomial functions of temperature.

  For cases with species transport and volumetric reactions, it is best practice to specify the specific heat capacity $C_p$ as a polynomial that is a function of temperature. See Sections  15.1.3 and 8.7.2 for information on defining material properties for the species in the mixture.

  Materials

• Assign a non-zero value for the density when selecting boussinesq.

  The Boussinesq model is used for natural convection problems involving small changes in temperature. To enable the Boussinesq approximation for density, choose boussinesq from the Density drop-down list in the Create/Edit Materials dialog box and specify a constant value for Density. See Section  8.3.3.

  Materials

• Review the absorption coefficient. Default value detected.

  If any of the radiation models are enabled. Enter an absorption coefficient for the material listed (Section  8.8).

  Materials

• Assign a non-zero thermal expansion coefficient when selecting the Boussinesq density model.

  When selecting boussinesq to describe the density of your material, be sure to enter a valid thermal expansion coefficient for your material. For detailed information on the Boussinesq model, see Section  13.2.4.

  Materials