In analyzing the performance of a thermal system, the engineer must be able to identify the relevant heat transfer processes. Only then can the systems behavior be properly quantified. For the following systems, identify the pertinent processes, designating them by appropriately labeling arrows on a sketch of the system.

a) System 1: Identify the heat transfer processes that determine the temperature of an asphalt pavement on a summer day. Write an energy balance equation for the surface of pavement.

b) System 2: A honeycomb-like insulation material is used in buildings as shown below, where the solid part is a plastic and space between is air. Use qcond, qconv, qrad and an arrow to show the direction and type of heat transfer for conduction, convection, and radiation. Assume we have reached steady-state such that all heat that is coming in is going out.

Cold Side Hot Side