Dynamic Behaviour of Multistream Plate-fin Heat Exchangers

摘要

A general analytical solution for the calculation of dynamic responses of one-dimensional flow multistream plate-fin heat exchangers to disturbances in supply temperatures and flow rates is obtained. The problem is solved by means of Laplace transform and numerical inverse algorithm. By introducing four matching matrices, the solution can be applied to the exchangers with arbitrary arrangements, connections, bypasses, stream splitting and rejoining. For arbitrary supply temperature disturbances and an initial step change in flow rates, the problem is linear and the solution is exact. If the disturbances in flow rates are small, the linearized model is a good approach to the dynamic responses of the exchangers.