Um ajuste à equação de Sârbu e Borza para estimativas de rendimento de bombas em ocasiões de redução de velocidade

Abstract

The use of variable speed pumps is a strategy used to reduce energy costs in pumping systems. When the speed is changed, the operating point of the pump is moved so that it starts operating under new flow conditions, gauge height and, consequently, efficiency. In this way, it is necessary to determine the efficiency of a pump at its new operating point. In the literature, there is an empirical formula that proposes an estimate for this new income (formula of Sârbu and Borza). This work aims to evaluate the accuracy of the results offered by this formula and then propose an adjustment in its exponent in order to make its estimates more accurate. For this, the catalogs of fifty bombs were chosen, ten of each of five brands being branded. In each pump, three speed reduction tests were performed. In each test, the yield at the new operating point estimated by the fitted formula was compared to that calculated by the Affinity Laws and the estimated by the original formula of Sârbu and Borza.