Numerical Study of Venturi Technology for Heat Transfer

Many industrial engineers and companies have sought to develop new types of heat exchangers with lower energy consumption and thermal efficiency improvement. Most heat transfer enhancement techniques utilize expensive nanomaterials, add films inside the exchanger tubes, or increase the size of the exchanger. The current work examines the Venturi tube design's effects on thermal efficiency, pressure drop, and friction factor. Using ANSYS FLUENT and the RNG k-ε turbulent model, the study compares three cases: a smooth straight tube (S.S.T), a smooth unfinned Venturi tube (S.V.T), and a Venturi tube with annular fins (F.V.T) with Re (6000-34000) and a turbulence intensity of 5%. Air temperatures of 30-50°C and water velocity (0.11, 0.2, 0.3)m/s were applied. The F.V.T provides a significant increase in heat transfer rate with an improvement of 90.6% than S.S.T. The F.V.T has a higher outlet temperature than S.S.T of a percentage of 14%, while S.V.T has 9% relative to S.S.T due to the unique and distinctive shape of the Venturi tube. The results show that the Venturi tube significantly increases Heat Transfer Efficiency compared to S.S.T, such as Nu of F.V.T has 450.6 and S.V.T about 209.9 while S.S.T has 40. The effectiveness results of the exchangers show that Venturi tubes have a higher value than S.S.T, where F.V.T is 0.176,   S.V.T is 0.075, and S.S.T is 0.022.  The pressure drop in S.V.T is higher than S.S.T, about double. The friction factor of V.T is lower than S.S.T, where S.V.T is about 0.034, and F.V.T is 0.35, while S.S.T is 0.038, demonstrating the potential of Venturi designs in optimizing heat exchanger performance.