The aim of this paper is to analyse the fracture behaviour of energy materials for application in electrical engineering, and also to determine the relevant parameters that contribute to higher critical values of fracture toughness. The quality assessment of high temperature resistance steel used for pressure vessels of innovative construction of a linear oscillatory synchronous generator designed to be used in a freepiston Stirling engine was determined. For all testing of pressure vessel and the steel specimens the standard test procedures were used.
Słowa kluczowe: fracture test, energy materials, Stirling engine, synchronous machine, electrical engineering
Celem artykułu jest analiza zachowań niszczących materiały energetyczne w elektrotechnice, jak również określenie istotnych parametrów, mających wkład w wyższe wartości krytyczne wytrzymałości na złamania. Przeprowadzono ocenę jakości stali odpornej na wysokie temperatury używanej w naczyniach ciśnieniowych innowacyjnych konstrukcji generatorów synchronicznych do beztłokowego silnika Stirlinga. W celu wykonania testów naczyń ciśnieniowych oraz próbek stali użyto standardowych procedur badawczych.
Keywords: test wytrzymałościowy, materiały energetyczne, silnik Stirlinga, maszyna synchroniczna, elektrotechnika
The basic operation topology of Stirling engine is implemented when the engine receives thermal energy and converts it into mechanical movement. Conversion is possible with three different types of Stirling engine, alpha, beta or gamma type. All three types need an external source of thermal energy. It can be provided by different conventional energy sources or renewable energy sources in applications with external combustion. Stirling engine is most often used in micro Combined Heat and Power (μCHP) applications, which are mostly based on renewable energy sources. Versions with mirrors, using solar energy, and versions with external combustion of e.g. biomass, are used. A pressure vessel is a component of Stirling engine as container designed to hold gases or liquids at a pressure substantially different from the ambient pressure. Pressure vessels can be dangerous, and fatal accidents have occurred in the history of their development and operation, thus in present research determination of quality assessment of high strength steel used for pressure vessel design is necessary [1-4]. Pressure vessel of prototype Stirling engine operated under 210 OC as a hot cylinder and it is made by high temperature resistance steel 10CrMo10V5 and welded together with two undermached welds (Fig. 1). In the assessment of pressure vessels as a welded structures the consideration of both strength mismatching and transferability cannot be avoided. In this paper we first review the effects of the mismatch observed in pressure vessel with two welded joints on strength and fracture, and show that the plastic constraint due to strength mismatching plays an important role in fractureinitiation behavior for ductile and brittle cracks which appeared in the pressure vessels . Finally, for all testing of pressure vessel and the steel specimens the standard test procedures were used for determining the weldability and quality assessment of hig [...]
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