Effects of helical fins with semi-circular in cross-section on the performance characteristics of novel finned-cyclone separators

摘要

Separation of particles (solid) from hot gases were carried out with the help of cyclone separators in most of the power generation industries (fluidized bed boilers) and process industries. Present research focuses on improving the performances of such devices by modifying the geometry. Conventional 2D2D Lapple type cyclone separator geometry was modified by attaching semi-circular cross-section helical fins along the height of barrel wall to make it as finned-cyclone separators. Semi-circular helical fins attached on the barrel wall varies (six-sets) with size (5 mm, 7.5 mm, and 10 mm) and pitch (30 mm and 50 mm). 3D computational fluid dynamics simulations were carried out using ANSYS 15.0 tool and validation were performed with experimental data available in the literature for conventional 2D2D Lapple type cyclone separator before proceeding towards simulations of semi-circular finned-cyclone separators. Improved performance was noticed from all selected six cyclone separators with semi-circular fins (cswf) when compared to conventional cyclone separators while studying the fluid mechanics characteristics, which directly influences on collection-efficiency of cyclone separators. Among selected cyclone separators, the cswf with size of fin 7.5 mm and fin-pitch 50 mm was noted to be performing improved collection efficiency for the particles size <3 mu m. Around 5%-11% improved collection efficiency when compared to conventional cyclone separators were observed in the study by fixing the semi-circular fins along the height of barrel wall without disturbing the main role of cyclone separator, which is separating the very fine particles, which would otherwise causes pollution.