This article presents an overview of the Blade Mechanics Seminar hosted annually in Winterthur by Zurich University of Applied Sciences. This seminar is co-organized by the Swiss Section of the ASME and focuses on the common need for knowledge base analyses. It offers a platform for know-how and experience exchange between engineers from various turbomachinery companies. The Blade Mechanics Seminar aims to answer the participants' needs that arise in their daily work regarding axial and radial bladed discs of aero-engines and industrial turbines. A one-hour keynote speech given by an expert from the industry opens the one-day seminar that also includes a few presentations followed by comprehensive discussions on the understanding of the presented problems and their solutions. As a discussion forum, this seminar highlights many dimensions of the state of the technology and methodology applied to blade analysis. In 2010, non-destructive testing of component properties was demonstrated at Alstom's booth, providing practical experience for finite element analysts.

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A rotating turbine or compressor blade is a piece of engineering art that brings various scientific disciplines together to convert as much thermodynamic energy into mechanical work as possible. This work drives the generator, producing electricity that has been an essential source of economic development and a better quality of life for over 100 years.11 Over 100 years of design experience have been incorporated in various design criteria to prevent blades from failing in service. From the mathematical point of view, the reliable operation of the rotating blade stands for meeting the aero-, thermo- and structural dynamics principals as an integrated solution explicitly given in the blade geometry and material.

Today's market requirements for higher engine performance drive the further development of the blade design towards 3D-blading technologies, sophisticated cooling schemes, new alloys and better thermal barrier coatings. These technical challenges do not conform with the conservative design criteria, which have to be elevated to a higher level of the engineering knowledge. Therefore, computational techniques are being employed to accelerate the research and development process. Modern clusters linking a hundred computers are able to simulate realistically the unsteady fluid-structure behaviour of the cooling process or of excitation, providing better understanding of the physics involved in the blade mechanics. New results and findings of these numerical and experimental studies are being published in hundreds of technical papers every year. The conference proceedings of international congresses, like the ASME Turbo Expo, become a huge database shared in many thousands of papers. A literature survey facilitates leveraging the individual knowledge, detailing what is most important for each company.

Indeed, the knowledge exists in both tacit and explicit form. Tacit technical knowledge is difficult to pin down because it is rooted in the expertise of individual engineers or researchers with many years of work experience. Different manners of sharing knowledge, such as design guidelines, lecture series, workshops, or · seminars help to identify the existence of tacit technical knowledge. This knowledge is routinely exploited in product development. The antipode is the explicit technical knowledge associated with comprehensible numerical analyses and experiments. Those investigations are triggered by the distinct needs of product development. Therefore, the explicit technical knowledge is easier to articulate than the tacit one. Or in other words, the tacit and explicit technical knowledge, respectively, correspond with the “personal” and “collective” knowledge of product. Both need to be managed in a way allowing the selection of the most competitive technologies to meet market and business requirements in the best way possible.

Focussing on the common need for knowledge base analyses, the Blade Mechanics Seminar, hosted annually in Winterthur by Zurich University of Applied Sciences (ZHA W) and co-organized by the Swiss Section of the ASME, offers a platform for know-how and experience exchange between engineers from various turbomachinery companies. The Blade Mechanics Seminar aims to answer the participants’ needs that arise in their daily work regarding axial and radial bladed discs of aero-engines and industrial turbines. A one-hour keynote speech given by an expert from the industry opens the one-day seminar that also includes a few presentations followed by comprehensive discussions on the understanding of the presented problems and their solutions. As a discussion forum, this seminar highlights many dimensions of the state of the technology and methodology applied to blade analysis. Long coffee breaks allow for various bilateral discussions or visits to the sponsors’ booths. In 2010, non-destructive testing of component properties was demonstrated at Alstom's booth (Fig. 1), providing practical experience for finite element analysts. Now, the Blade Mechanics Seminar is a local engineering event with a global footprint because in 2009 and 2010 one hundred engineers representing 21 companies and 5 universities from 12 countries took part in this event (Fig. 2).

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The seminar location in Winterthur, in the foothills of the beautiful Swiss Alps, is not incidental. This Swiss town is the cradle of turbocharger technology invented in 1905 by the Swiss engineer, Alfred Buechi. In 1908, the American Chadwick racing car was first equipped with ’Zoller rotary compressors’ (a centrifugal compressor) developed by the Swiss engineer, Arnold Zoller of Winterthur. 100 years ago in 1910,Joseph J. Murray constructed the first mechanically supercharged two-stroke aircraft engine for the Murray-Willat Company (see ’Early Flight exhibition’ in ’National Air and Space Museum’, Washington DC).The adjacent Swiss city of Zurich (30 km from Winterthur) became the cradle of the gas turbine technology engineered by Prof. Aurel Stodola. In 1939, the first gas turbine with a power output of 4 megawatt and an efficiency of 17.4 percent was installed in the municipal power station in Neuchatel, Switzerland. This oldest machine, which has been restored by Alstom in Birr (70 km from Winterthur), is recorded in the ASME historic landmarks.22 Participants of the 16th Blade Mechanics Seminar,33 to be held on 14th September 2011 , can also visit spectacular dammed lakes (e.g. Lake Grimsel) in the Swiss Alps that provide the water to drive 543 turbines of hydropower plants, generating 56% of the electricity in Switzerland.

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The 100 years are based on Parson's steam turbine innovation in 1884 and the first patent for a gas turbine by British inventor John Barber in 1791, but the idea of using water or steam kinetic energy dates back to the ancient times.