Investigation of Thermo-Hydraulics Flow and Augmentation of Heat Transfer in the Circular Pipe by Combined Using Corrugated Tube with Dimples and Fitted with Varying Tape Insert Configurations

Abstract

In various industrial applications, the high performance of heat exchanger demand is increasing. Subsequently, the energy resources depletion, for instance, in power plant, air-conditioning system and food processing systems. The important field for saving energy was through improving thermal performance, which can provide high performance heat exchanger. Present enhancing approaches can be classified by three changed types, which are passive technique, active technique and compound technique. Dimple, twisted tape and corrugated pipe are the passive heat improvement technique which includes more surface extensions. Hence, this research work concentrates on verifying the computational calculations of flow in the heat exchanger pipe with different surface extensions in the pipe. It is carried out for turbulent flow with a range of Reynolds number from 1000 to 15000 using CFD methods. The numerical outcomes illustrate that change twisted tape configurations have more effect on flow and heat performance. Experimental and numerical results agreement can confirm the simulation technique reliability, which adopts in this investigation. The deviation errors are observed by less than 6% compared with the normal pipe. Pressure drop increases due to the rise of twisted tape dimensions (width and thickness), leading to more mixing of fluid, secondary flow, and swirl flow inside the pipe. As the tape geometrical parameters increase, the f value also increases due to more variance in velocities flow between liquid layers, which are adjacent to tape surfaces a pipe wall, and pipe core flow layers, become higher. Correspondingly, compared to the normal pipe, twisted configurations can rise f about 5.4 to 33.5%. The better thermal evaluation factor is at a twisted tape of 1x1 mm at Re number of about 1000. The range value of the thermal evaluation factor is more than 1.67.