The flow maldistribution and the effect of different inlet configuration on the flow distribution in platefin heat exchangers were studied experimentally. It is found that the flow maldistribution is serious because o...The flow maldistribution and the effect of different inlet configuration on the flow distribution in platefin heat exchangers were studied experimentally. It is found that the flow maldistribution is serious because of the defects of inlet configurations, while the inlet configuration and Reynolds number are the main factors affecting the flow distribution. The improved inlet configurations, which are the header with a two-stage distributing configuration and the guide vane with a fluid complementary cavity were proposed and tested in this paper. The experimental results show that the improved inlet configurations can effectively improve the performance of flow distribution in heat exchangers.展开更多
Using embedded thermal sensors, dynamic thermal management(DTM) techniques measure runtime thermal behavior of high-performance microprocessors so as to prevent thermal runaway situations. The number of placed sensors...Using embedded thermal sensors, dynamic thermal management(DTM) techniques measure runtime thermal behavior of high-performance microprocessors so as to prevent thermal runaway situations. The number of placed sensors should be minimized, while guaranteeing accurate tracking of hot spots and full thermal characterization. In this paper, we propose a rigid sensor allocation and placement technique for determining the minimal number of thermal sensors and the optimal locations while satisfying an expected accuracy of hot spot temperature error based on dual clustering. We analyze the false alarm rates of hot spots using the proposed methods in noise-free, with noise and sensor calibration scenarios, respectively. Experimental results confirm that our proposed methods are capable of accurately characterizing the temperatures of microprocessors.展开更多
基金Supported by the Doctoral Foundation of Xi'an Jiaotong University (No. DFXJTU2002-12) the Foundation for Excellent Doctoral Dissertation Author by Minister of Education, China (No. 199933).
文摘The flow maldistribution and the effect of different inlet configuration on the flow distribution in platefin heat exchangers were studied experimentally. It is found that the flow maldistribution is serious because of the defects of inlet configurations, while the inlet configuration and Reynolds number are the main factors affecting the flow distribution. The improved inlet configurations, which are the header with a two-stage distributing configuration and the guide vane with a fluid complementary cavity were proposed and tested in this paper. The experimental results show that the improved inlet configurations can effectively improve the performance of flow distribution in heat exchangers.
基金the National Natural Science Foundation of China(No.61501377)
文摘Using embedded thermal sensors, dynamic thermal management(DTM) techniques measure runtime thermal behavior of high-performance microprocessors so as to prevent thermal runaway situations. The number of placed sensors should be minimized, while guaranteeing accurate tracking of hot spots and full thermal characterization. In this paper, we propose a rigid sensor allocation and placement technique for determining the minimal number of thermal sensors and the optimal locations while satisfying an expected accuracy of hot spot temperature error based on dual clustering. We analyze the false alarm rates of hot spots using the proposed methods in noise-free, with noise and sensor calibration scenarios, respectively. Experimental results confirm that our proposed methods are capable of accurately characterizing the temperatures of microprocessors.
