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REVIEWED BY FRANK M. WHITE These two volumes mark the beginning of a new clothbound series of review articles on fluid dynamics and other aspects of transport processes. The articles are wide-ranging, with a diverse international authorship. The books are printed in India with excellent type composition and clear, sharp figures. However, the paper is of rather poor quality-thin, rough, and porous-the benefit to the reader being a considerably lower price than comparable review series. Volume I presents five reviews of about 50 pages each: Blood Flow, by V. L. Shah; Two-Phase Gas Non-Newtonian Flow, by R. Mahalingam; Mass Transport in Electrochemical Systems, by T. Z. Fahidy and S. Mohanta; Numerical Methods for Viscous Flow Problems, by M. M. Gupta; and Mixing of Viscous Newtonian and Non-Newtonian Fluids, by V. V. Chavan and R. A. Mashelkar. In general, the articles are less general than they sound. For example, Shah's blood flow review is primarily concerned with entrance and diffusion effects in straight tube flow. Similarly, Gupta's numerical methods review concentrates on the traditional stream function/vorticity technique plus a brief discussion of the MAC method. One senses that these articles, though very interesting to the nonexpert such as this reviewer, are not presenting the state of the art as described, say, in the program of the last ASME Winter Annual Meeting. They do serve the goal expressed by the editors that engineer readers learn about scientific advances in transport processes while scientists learn about the practical problems to be faced. Volume II contains six reviews: Modelling of Aquatic Systems, by L. T. Fan et al.; Non-Newtonian Circular Entry Flows, by D. V. Boger; Electrohydrodynamic Enhancement of Convective Transfer, by F. A. Kulacki; Dust Removal from Gas Streams by Filters, by S. C. Saxena and W. M. Swift; Multiphase Flow Models, by R. W. Lyczkowski et al.; and Movement of Particles in Flow Fields, by H. Brauer. Again the work may be somewhat dated and not too general. Brauer's review of particle motion, for example, leans heavily on simple drag correlations and flow field descriptions and is much less general than a gas-particle textbook we reviewed here in December 1981. The review of multiphase flow models does seek generality at the expense of being utterly uncritical: model after model is thrown at us without recommendations or judgments. Kulacki's review of electrohydrodynamic enhancement was especially interesting and educational. This new review series serves a good purpose of educating engineers to new fields of fluids engineering. They are recommended especially for library acquisition.

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Experiments were conducted to study transition to turbulence in pipe flows started from rest with a linear increase in mean velocity. The data were taken at the Unsteady Flow Loop Facility at the Naval Underwater System Center, using a 5-cm diameter pipe 30 meters long. Instrumentation included static pressure, wall pressure, and wall shear stress sensors, as well as a laser Doppler velocimeter and a transient flowmeter. A downstream control valve was programmed to produce nearly constant mean flow accelerations, a, from 2 to 12 m/s2. In each of 37 runs, the time of transition to turbulence was the same throughout the pipe to within ± 30 ms, indicating a global instability. As acceleration increased, the transition Reynolds number ReD increased monotonically from 2 × 105 to 5 × 105. Other dimensionless transition parameters are also presented, the simplest and most effective of which is T* ≈ 400 ± 10 percent for the present experiments, where T* = ttr(a2/ν)1/3 and ν is kinematic viscosity.

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