11R46. Fundamentals of Thermal-Fluid Sciences. - YA Cengel and RH Turner (Dept of Mech Eng, Univ of Nevada, Reno NV). McGraw-Hill, New York. 2001. 1047 pp. CD-ROM included. ISBN 0-07-239054-9. $93.95.
Reviewed by R Smith (Dept of Mech Eng, Rensselaer Polytech Inst, Troy NY 12180).
The authors have prepared an undergraduate textbook that is directed at a rapidly evolving educational niche market. On the one hand, curricula such as electrical engineering or materials engineering, which previously had students take a nominal thermodynamics course to help round out their backgrounds, are now seeking an integration of fluid mechanics and heat transfer into that slot. In addition, some mechanical engineering programs are replacing the separate thermodynamics, fluid mechanics, and heat transfer courses with an integrated 2- or 3-term sequence.
The present text is one of the few available that may be suitable for each of these goals. It is essentially a major revision of a previous thermodynamics/heat transfer combination by the first author, to include several chapters in fluid mechanics fundamentals. In addition, the thermodynamics and heat transfer sections have been substantially reworked, with a previous awkward chapter on electronics cooling omitted. There is limited competition for this type of text at present. Both Introduction to Thermal Sciences, Second Edition, by Schmidt, Henderson, and Wolgemuth (Wiley, 1993) and Thermofluids, by Sherwin and Horsley (Chapman and Hall, 1996) are reasonable offerings, but in this reviewer’s opinion, do not match up in terms of production quality, number of examples, scope, and readability. Earlier classical texts in transport phenomena (eg, Bird, Stewart, and Lightfoot or Rohsenow and Choi) are written at too high a level for most introductory courses.
This text is organized so that after a coverage of the first five or six chapters in thermodynamics, an instructor can mix and match additional sections. For instance, all of fluid mechanics could be skipped in lieu of additional coverage of entropy and power and refrigeration systems in addition to some heat transfer topics. Alternatively, the heat transfer could be de-emphasized for civil engineering students needing more exposure to fluid mechanics. Electrical engineers might skip second law and entropy usage all together and spend more time on heat transfer. Mechanical engineering students could cover the entire text in a two-semester course, possibly with some augmentation to add a bit of depth. A real strength is the readability of the book and the extensive use of clever illustrations. There are numerous end-of-chapter problems organized into categories, including “concept” questions. The publisher maintains a useful website with instructional materials, and the popular EES™ software can be bundled with it. (However, nothing in the text itself refers directly to EES™, and its use is not required.)
Space does not permit a detailed subject-by-subject review of this book. However, here are a few of the highlights. The authors have attempted to by-pass the sign convention problem associated with work and heat in the first law, opting for an and approach. However, they do return to the mechanical engineering notation later in terms of Energy and specific heat are presented as properties before heat and work are discussed, in hopes that the confusion over and might be avoided. All forms of mechanical work are discussed together, including flow work. Open and closed systems are given a uniform treatment to emphasize the commonality of energy balances for both types of systems.
The five chapters on fluid mechanics focus on macroscopic mass, momentum, and energy balances on control volumes. They are simple and practical. Neither the Navier-Stokes equations nor the Euler equations are to be found, and discussion of the behavior of flow fields is strictly qualitative and conceptual. However, this section offers the tools that most students can apply in the field for pipe flows and flows around objects where simple lift, drag, and pressure drop are desired. A flaw is the derivation of a Bernoulli equation by making a force balance on a streamline with no friction, but then applying it to control volumes as an energy equation with friction (head loss). Clearer to this reviewer (at this level) would be a control volume energy balance with internal energy changes lumped into the head loss term. When the control volume momentum balance is derived, the authors resort to the greatest mathematical detail of the text, in terms of the general Reynolds transport theorem. However, they fail to note that when force balances are made on macroscopic systems such as pipe flows, the pressures must be gauge pressures, not absolute. (For all their examples, one inlet or outlet is at atmosphere pressure, so the error doesn’t enter; however, it would for some problems.)
The remaining chapters on heat transfer are quite similar to those of most heat transfer textbooks, albeit with simplified presentations and limited analysis. The general conduction and convection equations are omitted; however, there is strong emphasis on thermal resistance concepts and on applications of correlations for heat transfer coefficients in forced and free convection. Radiation and heat exchangers are also given reasonable, but limited coverage.
Overall, the text accomplishes most of what the authors desired. It is simple and practical and can be applied to a variety of instructional environments. It is not a unified treatment of thermal-fluid sciences, however. Fundamentals of Thermal-Fluid Sciences is a useful combined thermodynamics, fluid mechanics, and heat transfer textbook for courses where the purchase of three different books might be awkward and expensive.