Abstract
Flow and heat transfer characteristics were examined experimentally on vertical flexible channels in a heat exchanger simulating the thermal energy storage tank with PCM rod capsules. The channels were formed as the gaps, which were composed of 7 flexible circular heating rods, 34 mm OD. x 1.5 m high, packed vertically in a tubular container of 104 mm ID. One rod in the center of the container was surrounded by the other 6 rods. Difference between the water flow rates in 6 smaller channels (around the central rod) and in the other larger ones (composed of the outer 6 rods and the container wall) was much smaller than expected. This showed the existence of the cross flow between the inner and outer channels caused by the deformation of the rods. The heat transfer rate was increased by about 25 %, which might be due to the heat transportation by this cross flow.
