I have one chamber model. There are two objects inside that chamber in which one object which acts as a heat source is maintained at higher temperature than other object. These two objects are placed very close to each other  due to which there is rise in temperature of second object. I want to calculate what flow rate of air should I need to maintain so that there is no change in temperature of second object. So for this how should I setup ( means boundary conditions or any other specific parameters ) means whether I have to take it as internal or external analysis ??