Simulation of new design heat-exchange equipment for microclimate maintenance systems in poultry houses

This article is a continuation of the improvement of the microclimate maintenance systems in poultry houses, and the goal is to develop and numerically simulate a new design heat exchanger as an element of the ventilation system. When developing new types of heat exchanger designs, an important role is played by factors, such as their weight and size characteristics, the efficiency of heat transfer through the surface, separating the heat carriers, the pressure losses in the pipes for each of the heat carriers, and other parameters, characterizing the heat exchanger. The paper considers a shell-and-tube heat exchanger with a shell of rectangular cross section with a transverse flow around the pipe bundles. The geometry of the arrangement of pipes with a diameter of d = 10 mm is peculiar, differing from the traditional chess-like, corridor, and compact bundles. The neighbouring pipes in such close bundles are displaced relative to each other by a distance of 1 mm. Besides, three types of a bundle design are considered, in which there is a displacement of the pipes in the transverse direction along the entire length of the pipe bundle by 10 mm, 12 mm and 15 mm. Since the entire row is offset by different distances, the number of the rows of the pipes changes. The number of pipes in one row, with a diameter of 10 mm, contains 102 pc, consisting of 2 collectors. Height of the pipes is 1 m. Computer mathematical modelling of the heat and mass transfer processes in the pipe bundles of different geometry with a compact arrangement of tubes was carried out, using the ANSYS Fluent software package. A mathematical model is based on the Navier-Stokes equation, the energy conservation equation for convective flows, and the continuity equation. The standard k-ε turbulence model was used in the calculations. The fields of velocities, temperatures, pressures in the studied channels are obtained. Conditions of the hydrodynamic flow in the channels are analysed, and the intensity of the heat transfer between the hot and the cold coolant through the wall, separating them, is estimated. More efficient heat exchange surfaces are determined and the prospects of using the proposed designs of the pipe bundles in the design of the heat exchangers for various purposes are shown.