Краткое описание

Spatial variation of transient behaviour of a counter current heat exchanger is studied while a flow rate step is applied. The linear evolution of time constants of both fluids, allows to obtain their analytic expressions by taking considerations on the boundaries of the heat exchanger. The confrontation of the theoretical results to experimental data allowed to validate the analytical relations witch depend on initial and final steady states. The influence of flow rate step magnitude on transient behaviour is studied by maintaining initial steady state. In the same manner, effect of initial steady state is investigated with a constant flow rate step. Comparison between response time to positive and negative flow rate step is also presented.