<strong>Paper Title</strong><br>
An Experimental Investigation Into Thermal Energy Storage Of A Coil-In-Shell Heat Exchanger Connected To A Heat Pump Using Different Refrigerants<br>
<br>

<strong>Abstract</strong><br>
The present experimental study investigates thermal energy storage of a coil-in-shell heat exchanger connected 
to a heat pump using different refrigerants. This highly efficient heat exchanger helps minimize a temperature difference 
between the shell-side fluid and the coil-side fluid, thereby enhancing the transference of the thermal energy between two or 
more fluids at different temperatures and in thermal contact. The performances of the coil-in-shell heat exchanger connected 
to the heat pump  using different refrigerants were investigated in the present work. The effects of R134a and R22 
refrigerants were analyzed in terms of heating times and power consumption. The results showed that the rate of heat transfer 
Q was 6.43 kW, based on the log mean temperature different (LMTD) of 36.2o
C and a heat exchanger Rayleigh number of 
3.1E9
. In addition, the effectiveness of heat exchange of the system connected to the heat pump was about 0.75 at the 
temperature difference of 33.6o
C and at the provided flow coefficient of 1.7. Finally, the room temperature after the cooling 
process and the relative humidity were found to have significant values with the use of the two different refrigerants R22 and 
R143a. 
 
Keywords— Thermal Energy Storage, Coil-in-Shell Heat Exchanger, Heat Exchanger Effectiveness, Rayleigh number, Heat 
Pump.