tailieunhanh - Design and Optimization of Thermal Systems Episode 1 Part 4

Tham khảo tài liệu 'design and optimization of thermal systems episode 1 part 4', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | 2 Basic Considerations in Design The important terms that arise in the design and optimization of thermal systems have been defined and discussed in the preceding chapter. We are concerned with thermal systems that are governed by considerations of fluid flow thermodynamics and heat and mass transfer. The interaction between the various components and subsystems that constitute a given system is an important element in the design because the emphasis is on the overall system. Additional considerations that may not have a thermal or even a technical basis also have to be included in most cases for a realistic and successful design. Though selection of components or devices may be employed as part of system design the focus is on design and not on selection. Similarly analysis is used only as a means for obtaining the inputs needed for design and for evaluating different designs not for providing detailed information and understanding of thermal processes and systems. The synthesis of information from a variety of sources plays an important part in the development of an acceptable design. With this background and understanding we can now proceed to the basic considerations that arise in the design process. FORMULATION OF THE DESIGN PROBLEM A very important aspect in design as in other engineering activities is the formulation of the problem. We must determine what is required of the system what is given or fixed and what may be varied to obtain a satisfactory design. The final design obtained must meet all the requirements while satisfying any constraints or limitations due to safety environmental economic material and other considerations. The design process depends on the problem statement as does the evaluation of the design. In addition the formulation of the problem allows us to focus our attention on the quantities and parameters that may be varied in the system. This gives the scope of the design problem ranging from relatively simple cases where only a .