Experimental investigation on thermo-hydraulic performance of a helical plate heat exchanger

The current research presents an experimental study on heat transfer and fluid flow characteristics of a helical plate heat exchanger (HP-HEx). Helical plate with different pitches and cross sectional area of the flow channel was investigated for various fluid mass flow rates and inlet temperatures. The results show that the proposed heat exchanger performed an overall heat transfer coefficient (U) and exergy efficiency (eta(ex)) about 279.77 W/m(2).K and 60.87% respectively. Also, the HP-HEx showed effectiveness (epsilon) and number of transfer unit (NTU) reach about 0.694 and 1.79 respectively with pressure loss reached 202 kPa, for hot and cold fluids flow rate 0.083 kg/s and 0.07 kg/s at inlet hot and cold fluid temperature 45 degrees C and 28 degrees C respectively, and pitch = 56 mm. The pitch and cross sectional area of the flow channel variation can augment heat transfer rate and decrease the pressure loss. For pitch decreasing from 76 mm to 46 mm, the U, epsilon, NTU, eta(ex), and pressure loss increase by 50.60%, 22.39%, 50.60%, 10.35%, and 20.87% respectively. Empirical general correlations were obtained from the experimental data of the present study with maximum deviations about +/- 16.81%, +/- 13.33%, +/- 17.73%, +/- 16.60% and +/- 15.60% for U, epsilon, NTU, eta(ex), and pressure loss, respectively.