Enhancing the heat transfer performance of triangular-pitch shell-and-tube evaporators using an interior spray technique

Heat Transfer Enhancement of Square-Pitch Shell-and-Tube Spray Evaporator Using Interior Spray Nozzles

“…However, the liquid collectors proposed in [12] and [13] are ineffective in square-pitch shell-and-tube spray evaporators since the liquid film distribution differs from that in triangularpitch tube bundles. In a recent study, Chang et al [14] showed that the dry-out problem can be prevented in compact triangularpitch shell-and-tube evaporators by introducing liquid sprays within the bundle interior. In the present study, the same concept is applied to resolve the dry-out problem in square-pitch shelland-tube spray evaporators.…”

Experimental investigation on the heat transfer performance of falling film with deionized water on horizontal tubes

“…Parken, 9 Hu 10 and Mou 11,12 studied the influence of heat flux on the tube and concluded that the change in heat flux had no obvious influence on the heat transfer coefficient outside the tube, provided that the liquid film outside the tube completely underwent convective heat transfer. In a study of the influence of evaporation temperature on heat transfer coefficient outside the tube, Parken used water as the working medium, while Armbruster 13 used water and ethylene glycol as the working medium, Xu 14 used water as the working medium, and Chang 8 used R141B as the working medium. These studies indicated that the average heat transfer coefficient outside the horizontal tube increases with increasing evaporation temperature in the process of convective heat transfer.…”

“…(2) With less refrigerant, according to the design of the system, this kind of evaporator can reduce the amount of refrigerant by 20%-90%. 8 (3) The pressure drop of the refrigerant fluid outside the tube is very small, so temperature loss can be reduced.…”

Experimental investigation into effects of ultrasonic vibration on pool boiling heat transfer performance of horizontal low-finned U-tube in TiO2/R141b nanofluid

“…Chiou et al [15] showed that the evaporation heat transfer coefficients of pure R22 and R124 refrigerants for a micro-fin tube were around 1.5-3.0 times higher than those for a smooth tube. Chang et al [16] investigated the cooling efficiency of a heat exchanger system comprising a horizontal low-finned tube bundle with a triangularpitch. The results showed that the shell-side heat transfer performance was dominated by the nozzle orifice diameter, the heat flux rate, and the spray mass flow rate.…”