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131.
132.
This study examines the comfort criteria of ASHRAE Standard 55-2004 for their applicability in hospital environments. Through an extensive field survey conducted in a university hospital in Taiwan, 927 sets of data have been collected. Above half of the measured samples failed to meet the specifications of Standard 55 comfort zone due to improper humidity control. Acceptability votes by patients exceeded the Standard's 80% criterion, regardless of whether the physical conditions were in or out of the comfort zone. Thermal neutrality, preference and comfort range are compared with other studies conducted in office environments and Standard 55 criteria. Results of chi-square tests revealed that patients’ physical strength significantly effected their thermal requirements. The net effect of health yields a marked difference in thermal neutrality and preference, and also in the comfortable temperature range. 相似文献
133.
Thermal analysis of a ceramic coating diesel engine piston using 3-D finite element method 总被引:1,自引:0,他引:1
In this study, firstly, thermal analyses are investigated on a conventional (uncoated) diesel piston, made of aluminum silicon alloy and steel. Secondly, thermal analyses are performed on pistons, coated with MgO-ZrO2 material by means of using a commercial code, namely ANSYS. Finally, the results of four different pistons are compared with each other. The effects of coatings on the thermal behaviors of the pistons are investigated. It has been shown that the maximum surface temperature of the coated piston with material which has low thermal conductivity is improved approximately 48% for the AlSi alloy and 35% for the steel. 相似文献
134.
Stratis V. Sotirchos 《Chemical Engineering Communications》1985,39(1):259-276
The effects of thermal radiation on the pseudosteady state and transient behavior of porous char particles exposed to an oxygen containing environment are investigated. The numerical simulation results show that particles that do not interchange radiant energy with their environment are characterized by wider ambient temperature regions where multiple steady states exist, higher combustion rates, and lower burning times 相似文献
135.
本文用不同的测试技术和方法测定了锗酸铋(BGO)单晶的比热(300~800K)热膨胀系数(100~1100K)和导温系数(140~700K),进而导出了 BGO 单晶不同温度下的导热系数、定容比热、德拜温度和格虑内森数。本文还对 BGO 单晶热物理性质的变化规律作了理论解释。 相似文献
136.
137.
Kazutaka Chibana Chaedong Kang Masashi Okada Koji Matsumoto Tetsuo Kawagoe 《International Journal of Refrigeration》2002,25(2):83
Water-silicone oil emulsion with an additive, (C2H5O)3SiC3H6NH2, was examined as a heat storage material. A spiral tube used as a heat exchanger was immersed in a low temperature bath and the emulsion was circulated in the tube to make ice continuously. Ice was separated from the ice–liquid suspension in an outlet tank. The amount of formed ice, the temperatures of the inlet and the outlet of the heat exchanger, and the temperatures in the tube wall were measured and the overall heat transfer coefficient and the heat flux through the tube were calculated. Experiments were carried out, varying the flow rate, the temperature of cooling brine, and the thickness of tube wall. The condition under which slurry ice was formed continuously without adhesion of ice to the cooling wall was clarified. Though decrease in the thermal resistance of the tube increased the rate of ice formation or raised the brine temperature, it narrowed the range of the flow rate and of the brine temperature in which slurry ice was formed continuously. 相似文献
138.
139.
评述了二极管泵浦内腔倍频激光技术的发展现状,对解决中小功率下‘绿光问题’的理论及实验方案进行了比较分析,对高功率内腔倍频系统亦进行了初步探讨。 相似文献
140.
偶联剂处理硅灰石填充不饱和聚酯树脂的研究 总被引:2,自引:0,他引:2
对针状硅灰石 (L∶D≥ 10∶32 5目 )提纯后 ,采用偶联剂进行表面处理 ,将硅灰石按不同比例填充于不饱和聚酯树脂体系中 ,研究了材料的性能。结果表明 ,改性后的硅灰石可显著改善不饱和聚酯的性能。 相似文献