Numerical Studies on Effects of Blade Number Variations on Performance of Sludge Pumps

Abstract

The sedimentation of sludge in pangasius catfish ponds constitutes a notable challenge for the economic advancement of Vietnamese farmers. Sludge formation is the result of a composite process involving residual food, waste material, and algae, which undergo decomposition, thereby releasing hazardous gases such as hydrogen sulfide (H2S), ammonia (NH3), and nitrogen dioxide (NO2). These emissions subsequently diminish oxygen levels within the ponds, adversely affecting the growth of catfish. Removal of the accumulated sludge is deemed necessary every two months throughout the catfish cultivation cycle. A proficient sludge pump, designed to function effectively within the Vietnamese environmental context, becomes imperative to address this predicament. The primary objective of this research paper is to explore the influence of blade count on the performance metrics of a sludge pump. Given that pangasius ponds typically exhibit depths ranging from 2 to 4 meters, this study is predominantly centered on assessing pump performance within the specified head range of 2 to 4 meters. Employing the computational fluid dynamics (CFD) methodology, the research delves into the fluid dynamics of sludge pumps featuring impeller blades numbering 7, 8, 9, and 10. These pumps are modeled as semi-open impeller centrifugal pumps operating at a speed of 2200 revolutions per minute (rpm), with the k-e turbulence model and the time-averaged Navier-Stokes equation serving as the fundamental analytical framework.