Performance Evaluation Methods for Multi-stream Plate-Fin Heat Exchanger

Mathematical model of cross type multi-stream plate-fin heat exchanger is established. Meanwhile, mean square error of accumulative heat load is normalized by dimensionless, and the equations of temperature-difference uniformity factor are improved. Evaluation factors above and performance of heat exchanger are compared and ana- lyzed by taking aircraft three-stream condenser as an example. The results demonstrate that the mean square error of accumulative heat load is common result of total heat load and excess heat load between passages. So it can be influenced by passage arrangement, flow inlet parameters as well as flow patterns. Dimensionless parameter of mean square error of accumulative heat load can reflect the influence of passage arrangement to heat exchange per- formance and will not change dramatically with the variation of flow inlet parameters and flow patterns. Tempera- ture-difference uniformity factor is influenced by passage arrangement and flow patterns. It remains basically un- changed under a certain range of flow inlet parameters.