Paraffin wax in the partition wall type heat exchanger encumbers the heat transfer rate of the system because of its low thermal conductivity. The heat exchange rate of the heat storage system can be greatly improved by direct heat exchange between paraffin and air. Paraffin wax and air were used to study the heat transfer characteristics of air-paraffin direct contact heat transfer. The air at room temperature was injected into high-temperature (100-150℃) liquid paraffin through a distributor. This work examines the effects of superficial gas velocity

static liquid height and heat exchange temperature difference on the volumetric heat transfer coefficient and gas holdup rate in paraffin-air bubble heat transfer system. The results show that the volumetric heat transfer coefficient and the gas hold up increase by increasing the superficial gas velocity

and

for gas holdup

the growth rate is faster at lower superficial gas velocity. Increasing the height of the static liquid height will only lead to a decrease in the volumetric heat transfer coefficient and the gas holdup in the experimental conditions

and the effects of changing the gas liquid temperature difference on the volumetric heat transfer coefficient is not obvious. In addition

these effects are formulated in forms of empirical equations.