This paper presents an experimental and numerical investigation of the thermal performance of natural draft wet cooling tower (NDWCT). The experimental investigation is carried out under natural draft condition and forced draft condition created by an axial fan. The operational parameters considered in this study are the thickness of the fill (10 and 20 cm), inlet water temperature (40, 45, and 50 °C) and inlet water volume flow rate (5.68, 7.75, and 9.46 L/min). The experimental results showed that the thermal performance is improved when the fans are used with the NDWCT. The temperature difference between inlet and outlet and effectiveness increase by 35% and 37.2%, respectively at fill thickness of 20 cm and water volume flow rate of 11.35 L/min. The temperature distribution of the air and the relative humidity were numerically simulated for both cases of natural and forced draft by employing the commercial CFD software ANSYS Fluent 15. The experimental and numerical results were validated with results from a previous work and showed a good agreement. The experimental results showed that the effectiveness increase by 22% and 30% for NDWCT and FDWCT respectively when in case of fill thickness 20 cm.

An Air Conditioning Unit with magnetic field and different tubes was designed, fabricated and evaluated in this study. The Effect of magnetic field and different types of tubes on the performance of Air Conditioning was studied experimentally. A testing system of Air Conditioning Unit was developed as the test rig. The modified tubes as a straight tube before the condenser and after the evaporator were replaced by a finned bended tube with five bends and a coil finned tube with five turns. The experimental results for the temperature of refrigerant and the coefficient of performance for an air conditioning unit were presented. Changing the tubes and introducing electric charging has a significant effect on the performance of the unit. The electric charging has a positive effect of the performance of the system. The electric charging enhanced the performance by 76% in case of bent tube and by 177% in case of coil tube. The bent pipe increases the refrigerant temperature between 50% and 200%, while the coil pipe increases the temperature between 18 % and 190 %. • This method increases the refrigerant temperature for Air Conditioning system. • This method provides simple technical testing of Air Conditioning Unit with magnetic field and different tubes • This method can be useful to enhance the performance of Air Conditioning Unit.

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Heat transfer between a heated flat plate and normal impinging gas‐solid two‐phase jet flow was investigated. A single jet from a nozzle of 10 mm diameter at nozzle‐to‐plate distance/nozzle diameter ratio in the range of 2–8 was used. Natural sand particles with average diameters of 220, 350, and 550 μm were used as a solid phase. The effects of particle size and loading ratio (mass of sand/mass of air) at different jet velocities on impingement cooling characteristics of the flat plate are investigated. The numerical simulations were performed with ANSYS Fluent 14.7 for a steady, three‐dimensional, incompressible turbulent flow using Eulerian simulation for the gas phase and Lagrangian simulation for sand particles. The experimental results show that the existence of sand particles decreases the Nusselt number compared to air jet flow. The single and two‐phase flow experimental results are close to predictions when the particle reflection option is used in the simulation. The discrepancy in local values near the stagnation point can be attributed to the complex nature of the two‐phase flow at the stagnation point that includes reflection of sand particles at different angles.