Includes Part 1, Number 1: Books and Pamphlets, Including Serials and Contributions to Periodicals (January - June)

Sect 2. 317 tinuity surfaces 1. This suggests that a wake pressure Pw be associated with each flow past a bluff body, and that a wake parameter (2. 4) which plays the same role as the cavitation parameter (2. 1), be defined for the flow. This idea has been made the basis of a modified wake theory (ef. Sect. 11) which proves to be in good qu- titative agreement with pressure and drag measurements. It should be emphasized, however, that un h like the cavitation number, the wake parameter is a quantity which is not known a priori, and must be empirically determined in each case. (3) Jet flows. The problem of jet efflux from an orifice is one of the oldest in hydrodynamics and the first to be treated by Fig. 3a. the HELMHOLTZ free streamline theory. Of particular importance for engineering applications is the discharge coefficient Cd' which is defined in terms of the discharge Q per unit time, the pressure P, and the cross-sectional area A of the orifice, by the formula, (2. 5) where e is the fluid density. Two methods of measuring Cd have been most fre quently adopted. In the first the liquid issues from an orifice in a large vessel under the influence of gravity _,-____________ . , (Fig. 3 a), while in the second it 1 L is forced out of a nozzle or pipe under high pressure (Fig. 3 b).

This volume contains the contributions of participants of the conference "Optimal Control of Partial Differential Equations" which, under the chairmanship of the editors, took place at the Mathematisches Forschungsinstitut Oberwolfach from May 18 to May 24, 1986. The great variety of topics covered by the contributions strongly indicates that also in the future it will be impossible to develop a unifying control theory of partial differential equations. On the other hand, there is a strong tendency to treat prob lems which are directly connected to practical applications. So this volume contains real-world applications like optimal cooling laws for the production of rolled steel or concrete solutions for the problem of optimal shape design in mechanics and hydrody namics. Another main topic is the construction of numerical methods. This includes applications of the finite element method as well as of Quasi-Newton-methods to con strained and unconstrained control problems. Also, very complex problems arising in the theory of free boundary value problems are treated. ]~inally, some contribu tions show how practical problems stimulate the further development of the theory; in particular, this is the case for fields like suboptimal control, necessary optimality conditions and sensitivity analysis. As usual, the lectures and stimulating discussions took place in the pleasant at mosphere of the Mathematisches Forschungsinstitut Oberwolfach. Special thanks of the participants are returned to the Director as well as to the staff of the institute.

Bent Sørensen's Renewable Energy: Physics, Engineering, Environmental Impacts, Economics and Planning, Fifth Edition, continues the tradition by providing a thorough and current overview of the entire renewable energy sphere. Since its first edition, this standard reference source helped put renewable energy on the map of scientific agendas. Several renewable energy solutions no longer form just a marginal addition to energy supply, but have become major players, with the promise to become the backbone of an energy system suitable for life in the sustainability lane. This volume is a problem-solving tool for engineers, researchers, students, consultants, and planners currently working in the field, as well as a detailed map of the renewables universe for those looking to expand into new technological specialties, offering the most comprehensive coverage of the subject available. The book has been structured around three parts in order to assist readers in focusing on the issues that impact them the most for a given project or question. PART I covers the basic scientific principles behind all major renewable energy resources, such as solar, wind, and biomass. PART II provides in-depth information about how these raw renewable sources can actually be converted into useful forms, transmitted into the grid, and stored for future utilization. Finally, PART III undertakes the aspects of energy planning, environmental impacts, and socio-economic issues on regional and global levels. In this new edition, Sørensen presents his audience with updated data about renewables market penetration, current insights on climate change, the most recent available technology for renewable energy conversion, transmission and storage, and revised planning scenarios and the future outlook. - Covers the underlying physics and engineering of energy sources and conversion processes, including methodologies, models, and analysis - Provides a better understanding of the scientific basis and current progress in the field - Requires advanced knowledge of math and physics - Provides a unique three part organization covering energy sources, conversion processes, and the related planning, environmental impacts, and socio-economic issues on regional and global levels - New edition presents updated data about renewables market penetration, current insights on climate change, the most recent available technology for renewable energy conversion, transmission and storage, and revised planning scenarios and future outlook

Proceedings of the ICDE'96 held in Bandung, Indonesia

343 Whilst this may be so it is also true that this in itself is not sufficient to deter mine it completely. In fact the extent of the dead air region and the behaviour of the shear layer are also of prime importance and in short a unified treatment comprising external flow, boundary layer, shear layer and dead air region becomes necessary to complete the investigation. This would take us outside the scope of the present article and for the substantial progress that has been made towards such a treatment the reader is referred to a paper by HOLDER and GADD 1 and its comprehensive list of references. v. Heat transfer in incompressible boundary layers. 25. Introduction. The term fluid includes gases and liquids. Both gases and liquids are to some extent compressible but in many problems of fluid flow the density changes occurring are small. When they are small enough to be negligible we can regard the flow as incompressible. In Chap. IV we have established the equations for compressible flow of gases and these can of course be used to deter mine when density changes in a gas flow are in fact negligible. Broadly speaking this will be so when the temperature changes as determined by the energy equation are small enough.

This textbook gives an introduction to fluid dynamics based on flows for which analytical solutions exist, like individual vortices, vortex streets, vortex sheets, accretions disks, wakes, jets, cavities, shallow water waves, bores, tides, linear and non-linear free-surface waves, capillary waves, internal gravity waves and shocks. Advanced mathematical techniques ("calculus") are introduced and applied to obtain these solutions, mostly from complex function theory (Schwarz-Christoffel theorem and Wiener-Hopf technique), exterior calculus, singularity theory, asymptotic analysis, the theory of linear and nonlinear integral equations and the theory of characteristics. Many of the derivations, so far contained only in research journals, are made available here to a wider public.