Page 34 - Introduction to Computational Fluid Dynamics
P. 34

P2: IWV
            P1: JYD/GKJ
                                        0 521 85326 5
                           CB908/Date
                                                                                   May 20, 2005
            0521853265c01
                        EXERCISES
                           Chapter 5 deals with solution of complete transport equations on Cartesian grids. 12:20  13
                        Only 2D flow situations that may involve regions of fluid recirculation are consid-
                        ered. The transport equations now take the elliptic form. In essence, this chapter
                        introduces all ingredients required to understand CFD practice. In this sense, the
                        chapter provides a firm foundation for development of solution procedures employ-
                        ing curvilinear and unstructured grids. The latter developments are described in
                        Chapter 6.
                           Chapters 7–9 deal with special topics in CFD. In Chapter 7, the reader is in-
                        troduced to the topic of phase change. In engineering practice, heat and mass
                        transfer are often accompanied by solid-to-liquid, liquid-to-vapour, and/or solid-to-
                        vapour (and vice versa) transformations. This chapter, however, deals only with
                        solidification/melting phenomena in one dimension to develop understanding of
                        the main difficulties associated with obtaining numerical solutions. Chapter 8 deals
                        with the topic of numerical grid generation andmethods for curvilinear and unstruc-
                        tured grid generation are introduced. Finally, in Chapter 9, methods for enhancing
                        the rate of convergence of iterative numerical procedures are introduced.
                           There are three appendices. Appendix A provides the derivation of the transport
                        equations. In Appendix B, a computer code for solving 1D conduction problems is
                        given. This code is based on material of Chapter 2. Appendix C provides a computer
                        code for 2D conduction–convection problems in Cartesian coordinates. This code
                        is based on material of Chapter 5. Familiarity with the use of these codes, it is
                        hoped, will provide readers with sufficient exposure to enable development of their
                        own codes for boundary layer flows (Chapter 4) , for employing curvilinear and
                        unstructured grids (Chapter 6), for phase change (Chapter 7), and for numerical
                        grid generation (Chapter 8).
                           At the end of each chapter, exercise problems are given to enhance learning.
                        Also, in each chapter, sample problems are solved and results are presented to aid
                        their interpretation.





                        EXERCISES
                                                      terms in Equation 1.3 for i = 1, 2, and 3. Show
                         1. Express full forms of the S u i
                                                                                     = 0.
                            that if µ and ρ are constant then, for an incompressible fluid, S u i
                         2. Consider Equations 1.1–1.5. Assuming SI units, verify that units of each term
                            in a given equation are identical.
                         3. Show that summing of each term in Equation 1.2 over all species of the mixture
                            results in the mass conservation equation (1.1) for the mixture.
                         4. Consider the plug-flow thermo-chemical reactor (PFTCR) shown in Figure 1.4.
                            To analyse such a reactor, the following assumptions are made: (a) All  s vary
                            only along the length (say, x) of the reactor. (b) Axial diffusion and conduction
   29   30   31   32   33   34   35   36   37   38   39