Steady-state simulation of evaporators with R134a as a working medium

Abstract

The project Heat2Cool analyzes feasibility of thermally-driven cold generation in mobile applications. While in stationary cold generation, steady-state process simulation often meets the requeriments due to elevated thermal system system inertia. The basic conditions change in mobile system simulation. Mobile systems must exhibit higher performance densities, i.e. gravimetric and volumetric performance densities, in order to be energy efficient, which also results in higher system dynamics. In order to couple cooling device and engine simulation, dynamic models must be developed. The evaporator is one of the core components in the thermally-driven jet-ejector cycle. The task of the student is to diligently analyze the thermodynamic process in the evaporator. An adequate modeling approach of the heat exchanger must be chosen. A steady-state model including the decisive process parameters for the process simulation in Matlab/Simulink is supposed to be developed and implemented. The steady-state model should be formulated in a way that allows an extension to a dynamic model in the future. The model should account for different plate heat exchanger geometries and contain the according empirical equations for the heat exchanger coefficients from literature. Furthermore, the evaluation of teh evaporation process for different configurations should be performed on the basis of the simulation results. For this purpose, the student will work on a thesis at the Institute for Energy Conversion Systems of the TU Berlin of Prof.-Dr.-Ing. Felix Ziegler.