NUMERICAL INVESTIGATION FOR THE OPTIMAL PLATE HEAT EXCHANGERS THERMO-HYDRAULIC EFFICIENCY FITTED WITH FRAGMENTAL AND FRACTAL Y-SHAPED OBSTACLES
Sirine Chtourou, Hassene Djemal, Mohamed Kaffel, Mounir Baccar
Abstract
This manuscript covers a three- dimensional examination of the hydrodynamic and thermal efficiency of plate-type heat exchangers PHE fitted with Y-shape obstacles using the CFD code. The novelty of the evaluation is a new plate concept which is inspired by the human respiratory system structures. The Y shape obstacles placed on the plate gives birth of many parameters that influence strongly the heat flow, the thermal behavior and the pressure loss. The principal purpose of this study is to predict the influence of the Reynolds number Re (400-1400), the obstacles’ geometry (classical Y, frag-mental Y, fractal Y), the different geometrical parameters (the rib height h, the transversal pitch Pt and the longitudinal pitch Pl) and the arrangement type (rectangular and triangular) on the flow thermal characteristics and the heat transfer. The CFD analysis has been validated by the previous numerical and experimental studies. Using Ansys Fluent, the temperature and the velocity contours were presented and analyzed. Inside calculating the thermo-hydraulic performance parameter THPP, the fragmental Y with a triangular arrangement is the optimal configuration. It provides the maximum thermal efficiency factor THPP about 4.08 with a Reynolds number Re of 900.