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21.
热光伏发电系统中光伏电池运行温度是电池光电转换效率的影响因素之一,滤光片能有效降低电池表面温度。为了控制电池运行温度,设计了风冷装置和水冷装置,并通过实验发现在风冷装置中随着风扇功率的增大,电池背面温度逐渐降低,但当风扇功率达到一定值后,继续加大风扇功率,电池背面温度变化很小。在同等辐射器温度下,对比风冷,水冷可以使电池片背面温度降低到更低的值,电池冷却效果越好,电池的输出功率越高。  相似文献   
22.
国内外热塑性弹性体市场与产品开发进展   总被引:6,自引:0,他引:6  
重点介绍了热塑性聚烯烃弹性体(TPO)、热塑性硫化弹性体(TPV)、热塑性苯乙烯类弹性体(SBC)以及热塑性聚氨酯弹性体(TPU)等的国内外市场与技术开发和新产品进展。  相似文献   
23.
J. Karger-Kocsis  D. Felhs  D. Xu  A.K. Schlarb 《Wear》2008,265(3-4):292-300
The friction, sliding and rolling wear characteristics of thermoplastic dynamic vulcanizates (TPV; Santoprene® grades), composed of polypropylene (PP), ethylene/propylene/diene rubber (EPDM) and extender oil, were studied against steel counterparts in dry condition. The composition and basic mechanical properties of the TPV of various hardness (Shore A = 60°, 70° and 80°) were evaluated. The wear performance of the TPVs was investigated in different tribotests, viz. pin-on-plate (POP), cylinder-on-plate (fretting) and rolling ball-on-plate (RBOP), whereby “plate” was always the rubber. From the above tests the coefficient of friction (COF) and specific wear rate were determined. It was established that with increasing hardness usually both COF and the specific wear rate were reduced. Values of the COF and wear rate depended strongly on the configuration and testing parameters of the related tribotests. The wear mechanisms were concluded by inspecting the worn surfaces by white light profilometry and scanning electron microscopy (SEM), respectively, and discussed.  相似文献   
24.
目的寻找合适的硫化剂制备具有良好回弹性的聚乳酸(PLA)基动态热塑性弹性体(TPV)。方法以丙烯酸酯橡胶(ACM)作为橡胶相,分别选用三巯基均三嗪(TCY)、六亚甲基二胺氨基甲酸盐(HDC)、N,N'-双肉桂醛缩-1,6-己二胺(DHD)作为ACM/PLA共混体系的硫化剂,研究这3种硫化剂与ACM或PLA混炼过程的扭矩曲线变化。结果当每100 g橡胶-聚乳酸体系中添加0.75 g硫化剂时,该TPV的硬度适中,拉伸强度相对较高,断裂伸长率基本相当,永久变形率为最小(26%)。加入TCY硫化剂后,材料中的橡胶相由原来的球状颗粒转变为柱状颗粒,分布于PLA基体中。结论 TCY作为硫化剂能够制备得到具有良好力学性能的PLA基TPV。  相似文献   
25.
Thermophotovoltaic (TPV) power generation in gas-fired furnaces is attracting technical attention. Considerable work has been done in the area of low bandgap GaSb cell-based TPV systems as well as silicon solar cell-based TPV systems. Previous investigations have shown that a radiant burner with a high conversion level of fuel to radiation energy must be developed to realize an efficient TPV system. In our work, we investigated different natural gas-fired radiant burners in order to raise the conversion of fuel energy to thermal radiation. These burners were used as radiation sources to establish and test two TPV prototype systems. It was found that for a non-surface combustion radiant burner, the radiation output can be enhanced using a thermal radiator with a porous structure. Also, we developed a cascaded radiant burner that generates two streams of radiation output. One stream illuminates silicon concentrator solar cells while the other drives low bandgap GaSb cells. In this way, useful radiation output and thus TPV system efficiency are significantly increased due to the cascaded utilization of combustion heat and optimized thermal management.  相似文献   
26.
热塑性弹性体增韧聚丙烯的研究   总被引:18,自引:0,他引:18  
采用聚丙烯为基础树脂,以聚烯烃弹性体POE及共混型热塑性弹性体为PP的增韧剂,利用流变仪、差示扫描量热仪等手段及熔融指数、力学性能测试,比较研究了PP/POE及PP/TPV共混物的加工性、结晶性、流动性及力学性能.结果表明,POE作为增韧剂在加工性、增韧效果等方面更具优势,尤其在抗冲击强度方面效果更好。  相似文献   
27.
介绍了动态三螺杆反应挤出机的结构特征,采用动态三螺杆反应挤出机对EPDM/PP共混物进行动态全硫化挤出,并对其制品的物理力学性能进行了测试分析以及微观结构的电镜扫描分析,结果表明,由于在动态全硫化挤出的全过程中引入了振动力场,经动态三螺杆反应挤出机动态全硫化挤出的热塑性硫化胶(TPV)具有优化的微观结构,力学性能优异。  相似文献   
28.
采用高温开炼机制备了不同硫磺(S)用量的混炼型聚氨酯(MPU)/热塑性聚醚脂弹性体(TPEE)动态硫化热塑性弹性体(TPV),并探索了TPV重复加工性能和热油老化前后的物理力学性能。结果表明,随加工次数的增加,加入S后TPV的拉断强度先增加后减小,100%定伸强度逐渐下降;热油老化后,随S用量增加,TPV的拉断强度、100%定伸强度、断裂伸长率、硬度均呈现下降趋势,体积变化率减小,质量变化率不变。  相似文献   
29.
以高密度聚乙烯(HDPE)/三元乙丙橡胶(EPDM)热塑性硫化胶(TPV)为原材料、金相砂纸为模板,通过模压法在TPV表面构建超疏水层。结果表明:以金相砂纸为模板可在TPV表面获得具有较高保真度的微米级粗糙结构,模压过程中TPV表面发生的塑性变形使其具有比砂纸表面更复杂的粗糙结构;模压TPV表面具有良好的疏水性,当磨料规格高于W14时,模压TPV表面与水的接触角可达150°,滚动角小于10°,符合Cassie模型;采用W10砂纸模压的TPV表面具有较好的疏水性能。  相似文献   
30.
Currently, combustion-based micro power devices encounter the problem of low conversion efficiency. A miniaturized power generation system cascade utilizing thermal energy of a micro-combustor is proposed, because thermophotovoltaic (TPV) cells and thermoelectric (TE) modules work at different temperature levels. The system consists of a planar micro-combustor with a bended extension at the exit, two GaSb TPV modules to convert high temperature thermal radiation and two Bi–Te based TE modules attached to the bended extension to harness medium temperature thermal energy. The mathematical modelling approach to quantify the power output and conversion efficiency is systematically presented. The modelling results show that the integration of the TE modules could significantly improve the system efficiency. When burning the H2/air mixture, the overall system efficiency could reach 2.5% under the flow condition of U0 = 3 m/s and Φ = 1.0. Finally, measures for better thermal management to further enhance the conversion efficiency are discussed.  相似文献   
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