Author Result Khorasani et al.
(2017) The results exhibited a significant increase in the effectiveness and NTU of the heat exchanger as the air bubbles were injected. It is suggested that the disturbance and perhaps the turbulence intensity of the shell side flow are increased due to the motion of air bubbles resulting in an increment in the value of NTU and exergy loss Andrew et al. (2016) The main findings and correlations for the frictional two-phase pressure drops due to: steam-water flow boiling, R-134a evaporation and condensation, air-water two-phase flow and nanofluid flows are reviewed. Therefore, the purpose of this study is to provide researchers in academia and industry with a practical summary of the relevant correlations and supporting theory for the calculation of the two-phase pressure drop in helically coiled tubes. Sadighi Dizaji et al.
(2015) conducted experiments to study the effect of flow, thermodynamic and geometrical characteristics on the exergy loss in a vertical shell and coiled tube heat exchanger. Dizaji et al. (2015) studied experimentally the effect of air bubble injection on the heat transfer rate and effectiveness through a horizontal double pipe heat exchanger. Dizaji et al. (2015) increase the number of thermal units (NTU) and performance in a vertical shell and coiled tube heat exchanger via air bubble injection into the shell side of heat exchanger. Besides, exergy loss due to air bubble injection is investigated. Indeed, air bubble injection and bubbles mobility (because of buoyancy force) can intensify the NTU and exergy loss by mixing the thermal boundary layer and increasing the turbulence level of the fluid flow Kitagawa et al.
(2014) At constant bubble flow rate, the microbubble swarm shows a significant pulsatory rise along a vertical flat wall, particularly for small bubbles. Ankanna et al. (2014) focus on an increase in the effectiveness of a heat exchanger and analysis of various parameters that affect the effectiveness of a heat exchanger and also deals with the performance analysis of heat exchanger by varying various parameters like number of coils, flow rate and temperature. Aly (2014) a different behavior depending on the parameter selected for the comparison with the base fluid. Jamshidi et al.
(2013) the optimum condition according to the overall heat transfer coefficient for the whole heat exchanger is found. Results indicate that the higher coil diameter, coil pitch and mass flow rate in shell and tube can enhance the heat transfer rate in these types of heat exchangers Huminic et al. (2012) studied the purpose of this review summarizes the important published articles on the enhancement of the convection heat transfer in heat exchangers using nanofluids on two topics. The first section focuses on presenting the theoretical and experimental results for the effective thermal conductivity, viscosity and the Nusselt number reported by several authors. The second section concentrates on application of nanofluids in various types of heat exchangers: plate heat exchangers, shell and tube heat exchangers, compact heat exchangers and double pipe heat exchangers. Behabadi et al.
(2012) The thermo-physical properties of the working fluids were extremely temperature dependent; therefore, rough correlations were proposed to predict their properties.