Influences of optimizing the turbulator arrangement on the heat transfer and hydraulic characteristics of the tubular heat exchanger

Abstract

The Two-Tube heat exchangers due to their uncomplicated structure and high performance, have extensive use in the thermal engineering industries. Therefore, raising the performance and efficiency and the heat transfer capability is always a popular concept. Thus, the present paper has focused on the simulation and optimization of the application of the spiral-shaped turbulator in this kind of heat exchanger. A Computational Fluid Dynamic (CFD) code, which is 3D, is developed to solve the flow governing equations. So, 12 different cases (c1 to c12) are modeled with different spiral radii (R = 2 mm, 6 mm, and 9 mm) and pitches (500 mm, 250 mm, 100 mm, and 50 mm) to find the optimal position and configuration of the turbulator. The results indicated that c10 and c11 with R = 9 and with pitch = 250 mm and 100 mm can rise 168 % and 183.5 %, respectively, in Nusselt while increasing the pressure slippage compared to the base case. In the next part, it is endeavored to find the optimal base profile shape for the turbulator. Various profile shapes are examined and as a result, it is found that increasing the edge of the base shape increases the friction coefficient. On the other hand, the triangular base profile shape has the best thermal and hydraulic performance.