Strength Analysis of Structural Elements of Hydrogen Power-Generating Equipment
- PDF / 96,500 Bytes
- 8 Pages / 612 x 792 pts (letter) Page_size
- 117 Downloads / 186 Views
SCIENCE FOR PRODUCTION STRENGTH ANALYSIS OF STRUCTURAL ELEMENTS OF HYDROGEN POWER-GENERATING EQUIPMENT A. I. Belogurov, V. S. Rachuk, M. A. Rudis, A. M. Sushkov, and V. I. Kholodnyi The strength of materials and structural elements operating in contact with high-pressure gaseous hydrogen is studied as applied to the problems of hydrogen power-generating industry. The requirements to the design of structural elements operating in hydrogen are formulated. We propose a model of influence of high-pressure gaseous hydrogen on the strength and plasticity characteristics of structural materials and apply this model to the development of the corresponding procedures of strength analysis and evaluation of the cyclic fatigue life and durability of structural elements of hydrogen power-generating equipment taking into account the dislocation and diffusion mechanisms of hydrogen transport in the metal. The data on the properties of materials in hydrogen, the choice of the proper safety and durability margins, and the evaluation of admissible stresses in the structures are presented. The analysis of strength, cyclic fatigue life, and the number of cycles to failure are illustrated by special examples.
In the course of tensile testing of specimens in gaseous hydrogen in the temperature ranges 173–473°K and, especially, 273 – 293°K, their ultimate strength decreases by 10–40%, percentage elongation by 10–40%, and the true tensile strength (and, especially, relative narrowing) by a factor of three or even more [1–5, et al.]. Assume that the yield strength of materials in hydrogen remains practically constant and, in the elastic region, hydrogen does not affect their their mechanical behavior. This enables us to formulate some general approaches to the analysis of the influence of hydrogen in the design, strength analysis, and evaluation of the service life of structural elements of hydrogen power-generating equipment. The requirements to the service life of structures can be satisfied mainly by the maximum possible use of the desired properties of materials and contemporary technologies. As promising directions in the solution of problems of this sort, one can mention the attainment of high and stable structural strength of elements in the stage of design, the numerical–experimental evaluation of their strength, the number of cycles to failure, and durability, as well as the solution of related problems of materials science, technology, and operation, including full-scale tests. We studied the serviceability of structural materials in gaseous hydrogen at cryogenic, room, and elevated temperatures. The investigations were carried by numerous institutions but the leading role was played by the Karpenko Physicomechanical Institute of the Ukrainian Academy of Sciences and its “Proton” Center (V. I. Tkachev and his colleagues) [5]. The mechanical characteristics of materials in vacuum and in hydrogen at room temperature under a pressure of 30 MPa are presented in Table 1. In the course of the tests, the following major regularities of
Data Loading...
