航空发动机管壳式燃-滑油散热器换热特性计算

采用无量纲关系曲线(Re~St·Pr2/3)计算管壳式燃-滑油散热器管程、壳程表面传热系数,基于效率-传热单元数法建立了管壳式燃-滑油散热器换热特性计算模型;以航空发动机某管壳式燃-滑油散热器少量试验数据为基础,拟合得到了该型散热器管程和壳程Re~St·Pr2/3关系曲线,并将该关系曲线应用于另一结构类似的管壳式燃-滑油散热器换热特性计算.算例计算表明:计算值与试验数据吻合较好,管程、壳程出口温度相对误差均不超过6.5%,总换热量相对误差不超过7.4%.该方法可应用于航空发动机管壳式燃-滑油散热器设计及验证阶段的换热特性计算. 

Heat transfer characteristics calculation for aero-engine shell-tube fuel-oil heat exchanger

A dimensionless relationship (Re~St·Pr^2/3)was introduced for calculating the heat transfer coefficients in tube and shell sides of shell-tube fuel-oil heat exchanger, and a heat transfer characteristics calculation model of shell-tube fuel-oil heat exchanger was established based on efficiency-number unit method. Based on little experimental data of one shell-tube fuel-oil heat exchanger of aero-engine, the relationships of Re~St·Pr^2/3 were fitted for tube and shell sides of this heat exchanger, and the relationships were applied to heat transfer characteristics calculation of a similar shell-tube fuel-oil heat exchanger. A case study shows that the relative errors of the outlet temperature in tube and shell sides are less than 6.5% and the relative error of total heat transfer is less than 7.4%, indicating that the calculation results are in good agreement with experimental data. The method presented can be applied to calculate the heat transfer characteristics of aero-engine shell-tube fuel-oil heat exchanger in design and validation stages.