Use the Heat Source feature to add a domain heat source that generates sound. If a fluid is heated and cooled rapidly thermal expansion and contraction will generate acoustic waves. This could be a source representing a pulsating laser beam or a flame source in a combustion simulation. The feature adds a monopole domain source to the right hand side defined as

where the (isobaric) coefficient of thermal expansion αp is defined in terms of the speed of sound c, heat capacity an constant pressure Cp, ambient temperature T (this value is taken from the model inputs and can be space dependent), and ratio of specific heats γ.

Specify the Heat source strength Qheat (SI unit: W/m3).

Enter the additional fluid properties necessary to define the heat source. Enter the Heat capacity at constant pressure Cp (SI unit: J/(kg·K)) and the Ratio of specific heats γ (dimensionless). The default for both is From material, select User defined to enter a value or expression directly.