【摘要】 换热器操作型问题计算往往需反复试差或查取算图,计算繁复或有误差。为回避试差或查算图,对单程无相变换热器传热单元数与流体温度及热容流率比间的定量关系进行研究,导出了计算公式,对导出公式及获得的计算图表通过实例检验和分析。研究结果表明:用导出公式确定流体温度及介质消耗量可避免试差或查算图,方法简便、精度高;热容流率比存在临界值,在换热器设计及应用过程中需控制在临界值以下,以确保换热过程的经济性。更多还原

【Abstract】 The calculation of operation model of heat exchanger usually needs repetitious trial and error or look up ε-NTU figure,which is complex and has some error.In order to avoid these problems,the quantitative relationship between the number of heat-transfer units(NTU) and fluid temperature and the ratio of heat capacity vs.flow rate for one-way no phase changed heat exchanger was studied.By this way,a formula was obtained.Then the formula and the chart were verified and analyzed by an practical example.The results showed that by using the formula to calculate the fluid temperature and consumption of media can avoid repetitious trial and error or look up ε-NTU figure.The method is simpler and more precocious.Ratio of heat capacity vs.flow rate has a critical value.In order to get economical heat transfer process,the ratio of heat capacity vs.flow rate should be kept below its critical value in process of heat exchanger design and selection.更多还原