Zhengji Zhang – författare

This book concerns the theoretical foundations of hydro mechanics of Pelton turbines from a viewpoint of engineering. For reference purposes all relevant flow processes and hydraulic aspects in a Pelton turbine have been analyzed completely and systematically. The analyses especially include the quantification of all possible losses existing in the Pelton turbine and the indication of most available potential for further enhancing the system efficiency. As a guideline the book therefore supports further developments of Pelton turbines with regard to their hydraulic designs and optimizations. It is thus suitable for the development and design engineers as well as those working in the field of turbo machinery. Many laws described in the book can also be directly used to simplify aspects of computational fluid dynamics (CFD) or to develop new computational methods. The well-executed examples help better understanding the related flow mechanics.

This book concerns the theoretical foundations of hydro mechanics of Pelton turbines from a viewpoint of engineering. As a guideline the book therefore supports further developments of Pelton turbines with regard to their hydraulic designs and optimizations.

Dieses Fachbuch beinhaltet die wesentlichen Erkenntnisse der Hydromechanik von Freistrahlturbinen aus ingenieurwissenschaftlicher Sicht. Basierend auf theoretischen Grundlagen und im Sinne eines Nachschlagewerks werden die Strömungsprozesse und alle relevanten hydromechanischen Aspekte von Freistrahlturbinen möglichst vollständig und systematisch beschrieben. Sämtliche Verluste inklusive der hydraulischen Reibungseffekte werden behandelt und quantifiziert. Das Buch unterstützt somit die gezielte Weiterentwicklung von Freistrahlturbinen sowie deren hydraulische Optimierung und mechanische Dimensionierung. Es richtet sich an Entwicklungs- und Design-Ingenieure, an Turbinenhersteller, Kraftwerksbetreiber und Interessierte aus dem Bereich der Lehre und Forschung im Fachbereich „Strömungsmaschinen". Die zahlreichen angeführten Gesetzmäßigkeiten können zur Vereinfachung von numerischen Methoden in der Strömungssimulation (CFD) oder zur Entwicklung neuer Rechenmethoden verwendet werden. Ausgeführte Beispiele ergänzen einzelne Kapitel des Buches und tragen zum besseren Verständnis bei.

This technical book considers the application side of LDA techniques. Starting from the basic theories that are crucial for each LDA user, the main subject of the book is focused on diverse application methods. In details, it deals with universal methodical techniques that have been mostly developed in the last 15 years. The book thus gives for the first time an application reference for LDA users in improving the opticalconditions and enhancing the measurement accuracies. It also provides the guidelines for simplifying the measurements and correcting measurement errors as well as for clarifying the application limits and extending the application areas of LDA techniques. Beside the treatments of some traditional optical and flow mechanical features influencing the measurement accuracies, the book shows a broad spectrum of LDA application methods in the manner of measuring the flow turbulence, resolving the secondary flow structures, and quantifying the optical aberrations at measurements of internal flows etc.. Thus, it also supports the further developments of both the hard- and software of LDA instrumentations.