http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
냉동시스템의 압축기 신뢰성 시험 기간 단축을 위한 가속계수 설정
변종영(J. Y. Byun),이화(H. Li),정태영(T. Y. Jeong),정석권(S. K. Jeong) 한국동력기계공학회 2008 한국동력기계공학회 학술대회 논문집 Vol.2008 No.11
Compressor is a major component of a refrigeration system. Therefore many attempts to progress performances of the compressor have been conducted. The reliability qualification test is essential when a new product of a compressor is developed to guarantee life of the product under normal operation conditions. If the number of test sample is limited, the test period will be increase inevitably. In order to reduce the test period, we have to obtain an acceleration factor as some value through an acceleration life test. The process and methodology to establish the acceleration factor are investigated in this paper. The Weibull distribution and the Arrhenius relationship are adopted to estimate the acceleration factor under given assumptive temperature data. Finally a stress condition to satisfy the acceleration factor was formulated.
냉장고용 압축기의 무고장시험시간 주요 변수들의 영향 분석
변종영 (J. Y. Byun ),주우진 (W. J. Joo ),정태영 (T. Y. Jeong ),정영미 (Y. M. Jeong ),정석권 (S. K. Jeong ) 한국동력기계공학회 2009 한국동력기계공학회 학술대회 논문집 Vol.2009 No.6
This paper evaluates the influences of variables related to accelerated life test time for a compressor in a refrigerator to guarantee qualification life of it. At first, some equations applied to real industrial field for evaluating accelerated life test time are introduced. Then we investigate influences of the variables of the equations effected on the test time. Finally, we analyze the times obtained from each equation which is necessary for testing the compressor. It will be expected that relations between each equation can be cleared. Therefore, we can conduct accelerated life test of a refrigerator"s compressor within optimized minimum test time.
핫가스 바이패스방식에 의한 공작기계용 오일쿨러의 정밀 온도제어
변종영 (J. Y. Byun ),최준혁 (J. H. Choi ),문춘근 (C. G. Moon ),윤정인 (J. I. Yoon ),정석권 (S. K. Jeong ) 한국동력기계공학회 2009 한국동력기계공학회 학술대회 논문집 Vol.2009 No.6
Recently, technical trend in machine tools is focused on enhancing of speed and accuracy. The high speed usually causes thermal displacement and structural deformation of objects of the machine tool. To minimize thermal effect, machine tools adopt oil coolers with precise temperature control function. This study aims at precise control of oil outlet temperature in the oil coolers with hot-gas bypass based on PI control logic. The control system was designed for obtaining steady state error within ±0.2°C even though abrupt disturbances are added. We showed that the gain of PI could be easily determined by using gain-tuning method without any numerical model. Through some experiments, excellent control performance was established by a simple PI controller.
주우진(W. J. Joo),변종영(J. Y. Byun ),정태영 (T. Y. Jeong ),정석권 (S. K. Jeong ) 한국동력기계공학회 2009 한국동력기계공학회 학술대회 논문집 Vol.2009 No.6
This paper investigates optimum operating conditions to develop automatic system with high energy efficiency of a seawater ice machine which has rotating drum installed an evaporator inside it. The coefficient of performance(COP) was used as an index to evaluate energy efficiency of the machine and it was calculated by two different manners. The opening angle(OA) of electronic expansion valve(EEV)/controlvariable,wasadjustedwithin 50-100% range to estimate the energy efficiency of the machine. At first, we checked COP and superheat according to the variation of OA of the EEV and rpm of the drum. Then we analyzed that how the variation of OA and rpm of the drum have influence on the COP and superheat. Finally, we confirmed that optimum OA of EEV was 85~90% range and the rpm variation of the drum did not have influence on the COP and superheat.