Numerical Simulations and Research of Heat Transfer in Pneumatic Pulsator

Abstract

Abstract In loose material beds above silo outlets or in vertical channels immovable vaults can occur limiting or making impossible the downward movement of the loose material. To prevent vault creation or to destroy vault by aeration and separation of the loose material from encasing walls, a pneumatic pulsator can be applied. In order to optimize the head design, the flow phenomena were numerically simulated and the channels were preliminarily designed. The data obtained from simulation were also used as a basis for setting up an experimental stand to validate simulation results. During air flow in the channels due to frictional heat is produced, which is discharged from the pulsator to the environment. To increase the heat transfer in pneumatic pulsator, the external surfaces of channel are finned. Numerical simulations carried out conduction and convection heat transfer in the fins, and the results illustrated the temperature distribution on the surface of the body, the temperature distribution in the fins, stress distribution, value of factor of safety, the static displacement of the body and the distribution of air temperature along with the speed vectors. The results were compared with experimental and analytical results that confirm their correctness. The results confirm the rational design of the body in terms of thermal. The obtained temperature distribution using CFD agrees approximately with the values measured during the tests.