ABSTRACT
This chapter presents the basic aspects that are important in the design of thermal systems. The formulation of the problem is the first step in design and involves determining the requirements that must be met by the system, parameters that are given, design variables that may be changed in order to obtain an acceptable design, constraints that must be satisfied, and additional aspects arising from safety, environmental, financial, and other concerns. Conceptual design is the next step in the design of a thermal system. Originality and creativity are expressed in the form of the basic concept or idea for the design. The selected conceptual design leads to an initial physical system that is subjected to the detailed design process, starting with the modeling and simulation of the system. The model must be an accurate and valid representation of the physical system so that the behavior of the system may be investigated under a variety of conditions by using the model. Experimental results, material property data, and information on the characteristics of various devices are also incorporated in the overall model to obtain realistic and practical results from the simulation. The outputs from the simulation are used to determine whether the design satisfies the requirements and constraints of the given problem. If it does, an acceptable or workable design is obtained. Though several designs may be acceptable, the best design, optimized with respect to a chosen criterion, is essentially unique or may be selected from a narrow region of design variables. For a chosen system hardware, the operating conditions may also be optimized to obtain the best outcome.
