Experimental Study of Thermoelectric Heat Pump Water Heater with Exhaust Heat Recovery from Kitchens

A new kind of thermoelectric heat pump water heater for kitchens exhaust heat recovery was pre-sented,and its performances were investigated under different operating voltages.The experiment results show that the coefficient of performance decreases and the temperature difference between the hot and cold sides be-comes larger with the increase of the operating voltage,but the heating time becomes short.The higher the temperature of water,the greater the temperature difference between the hot and cold sides,leading to a smaller eoeffieient of performance.Under an exhaust temperature of 36℃,the coefficient of performance decreases from 1.66 tO 1.22 when the temperature of water increases from 28℃to 46℃with operating voltage 16 V.Performance tests illustrate that,compared with the conventional electrical water heaters,the new kind of ther-moelectric heat pump water heater is more coefficient.     

中心切割气相色谱法测定丁二烯抽提装置尾气全组成

建立了一种利用中心切割二维气相色谱法准确测定丁二烯抽提装置尾气全组成的分析方法。采用INNOWax毛细管色谱柱与Al₂O₃毛细管色谱柱串联，在线速度为30 cm/s，初始温度为48℃保持6 min、以8℃/min速率升温至150℃并保持10 min的程序升温色谱条件下，通过外标法和校正面积归一法，对丁二烯抽提装置尾气中碳四烃类和乙腈进行了测定。结果表明：在本文的实验条件下，碳四烃类和乙腈的分离效果良好；各组分的检出限（LOD）在1.2~2.4 mg/kg之间，相对标准偏差（RSD）均小于4.0%；本方法和已有方法测得的各物质含量接近，并且精密度不存在统计学上的差异。本方法仅需一次进样即可完成测定，检测速度快，结果准确可靠，适合丁二烯抽提装置尾气中全组分的测定。     

新型自动捕风排风装置排风口性能优化

基于自然通风原理,对所研制的自动捕风排风装置的通风性能进行了优化分析.通过数值模拟和实验研究,重点分析了排风口几何形状与其表面自然通风风压系数的关系,以及提高其排风性能的关键参数.研究结果表明,圆锥形渐扩口的综合排风性能为最佳,较无渐扩口的排风口可提高排风量14.3％;所研制的自动捕风排风装置在北京地区冬季典型天利用自...