Numerical simulation of a solar cooling system with and without phase change materials in radiant walls of a building

摘要

This work investigates energetically and financially a building solar cooling system with radiant walls which includes phase change materials (PCMs). The examined building has a floor area of 100 m(2) and it is located in Athens (Greece). The solar cooling system includes evacuated tube collectors coupled to a single-effect absorption chiller for producing cold water for the building radiant walls. The use of PCM is examined in all the building's outer walls and different scenarios with PCM in only some walls are also investigated in details. Different combinations of collecting areas and storage tank volumes are examined in order to determine the optimum design for every scenario. The study is performed with the commercial software TRNSYS which uses an active layer to simulate the radiant wall. The most important calculated parameters of this work are the auxiliary energy consumption, the solar coverage and the indoor temperature of the building. The results indicate that the best location of PCM layer is in south wall with a reduction of the auxiliary energy 30%, an increase of the solar coverage 3.8% and a reduction of the total system cost of about 3%.