통합 검색 | Korea Science

김진수;조수만;김윤재;김영진
- 대한기계학회논문집A
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- 제27권9호
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- pp.1531-1538
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- 2003
This paper compiles solutions of plastic $\eta$ factors and crack tip stress triaxialites for standard and nonstandard fracture toughness testing specimens, via detailed three-dimensional (3-D) finite element (FE) analyses. Fracture toughness testing specimens include a middle cracked tension (M(T)) specimen, SE(B), single-edge cracked bar in tension (SE(T)) and C(T) specimen. The ligament-to-thickness ratio of the specimen is systematically varied. It is found that the use of the CMOD overall provides more robust experimental J estimation than that of the LLD, for all cases considered in the present work. Moreover, the J estimation based on the load-CMOD record is shown to be insensitive to the specimen thickness, and thus can be used for testing specimen with any thickness. The effects of in-plane and out-of-plane constraint on the crack tip stress triaxiality are also quantified, so that when experimental J value is estimated according to the procedure recommended in this paper, the corresponding crack tip stress triaxiality can be estimated. Moreover, it is found that the out-of-plane constraint effect is related to the in-plane constraint effect.
https://doi.org/10.3795/KSME-A.2003.27.9.1531 인용 PDF KSCI

이춘태;박태근;정걸;헨리 팡가니반;정태진;백태현
- 한국정밀공학회:학술대회논문집
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- 한국정밀공학회 2006년도 춘계학술대회 논문집
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- pp.49-50
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- 2006
Photoelasticity is widely and conveniently used methods for whole field stress analysis. In this paper, 8-step photoelastic phase shifting method was performed by using a multi-purpose polariscope to measure the fringe orders along a specified line on the specimen containing a square hole. The material of the specimen is made of Polycarbonate. The measurement results by 8-step phase shifting method were compared with the those calculated by ABAQUS.
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송태원;손정락;김재환;김동섭;노승탁
- 대한기계학회:학술대회논문집
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- 대한기계학회 2001년도 춘계학술대회논문집D
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- pp.751-758
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- 2001
Exergy concept is applied to the analysis of part-load performance of gas turbine engine. Exergy is a useful tool to find the source of irreversibility in thermal system. In this study, details of the performance characteristics of a heavy-duty gas turbine, l50MW-class GE 7FA model, are described by theoretical investigations with exergy analysis. Result shows that exergy destruction rate of gas turbine increases with decreased load, which means increase of irreversibility. Also, it is found that variations of IGV angle and amount of cooling air for turbine blades are closely related to the inefficiencies of compressor and turbine, respectively.
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