Hybrid computer solution of heat exchanger partial differential equations

An attempt was made to solve the partial differential equations representing the kinetic behaviour of a counterflow heat exchanger on a hybrid computer. The partial differential equation in one space variable and time are replaced by differential-difference equations as an approximation, the differencing being done to the time variable, and these integrated for each time step by the analogue computer. The resulting solutions are stored digitally for replay to the analogue computer for the next time step.