DYNAMICS OF A HEAT TRANSFORMER WORKING WITH THE MIXTURE NAOH-H2O

The model described in the paper is based on the balance equations for mass and energy for the different apparatus such as absorber, generat or, evaporator, condenser and solution heat exchanger. It simulates a heat transformer process and ensures calculations not too time-consumi ng and much faster than in real time. With the aid of the model the tr ansient behaviour of a heat transformer working with the mixture NaOH- H2O is examined. For steady state operation the simulations agree well with experiments on a pilot plant. With NaOH-H2O as working substance s high COPs up to 0.49 were obtained with this heat transformer. For u nsteady state operation the deviations between experiments and simulat ions were slightly higher than those for steady state. The model never theless predicts the transient behaviour with a satisfying accuracy. A lso the startup and shutdown behaviour of a heat transformer was inves tigated under different conditions. (C) 1997 Elsevier Science Ltd and IIR.