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目前,国内广泛采用的是湿工况千球温度效率法来计算表冷器的湿工况。该法推导公式的数学模型清晰,推导过程严谨,计算比较方便。表冷器干工况时,空气和表冷器外表面之间热交换的推动力是干球温度差。但是湿工况时,空气和表冷器外表面之间的总热交换的推动是焓差,而不是干球温度差。所以,用干球温度效率公式计算表冷器的湿工况,物理概念不够明确;此外,由于该法中析湿系数ξ在校核计算时ξ是未知的,所以必须作烦琐的试算。这是该法的两个缺点。前几年国内有些同志提出过几种湿球温度效率
At present, the widely used domestic wet ball temperature efficiency method to calculate the wet conditions of the surface cooler. The mathematical model of the derivation formula of this method is clear, the derivation process is rigorous, and the calculation is more convenient. When the air cooler is dry, the heat exchange between the air and the outer surface of the cooler is the dry bulb temperature difference. However, during wet conditions, the total heat exchange between the air and the outer surface of the cooler is driven by the enthalpy difference rather than the dry bulb temperature difference. Therefore, using the dry-bulb temperature efficiency formula to calculate the wet condition of the surface cooler, the physical concept is not clear enough; in addition, because the dewaxing coefficient ξ in the method is unknown at the time of calibration calculation, a cumbersome trial calculation must be made. This is the two shortcomings of this law. In the past few years, some comrades in China have proposed several wet bulb temperature efficiencies.