Increasing the level of environmental safety of pumping units by energy saving during regulation.

Abstract

The relevance of improving calculation methods for pumping units of hydraulic systems in order to save energy and correspondingly increase their level of environmental safety is substantiated. To speed up hydraulic calculations and increase their accuracy, it is proposed to approximate the existing characteristics of centrifugal pumps, which are usually presented in the equipment passport in graphic form, with a quadratic parabola. The general equations for the analytical determination of the working point parameters, the construction of the pressure characteristics of the pump at a new rotation frequency and the formula for the geometric location of the tops of the pressure characteristics for different rotation frequencies of the impeller were obtained. It has been proven that with frequency control, the pump characteristic shifts equidistantly along the parabola of proportionality. In a similar way, the characteristics of the pump are affected by the casing of the impeller. An equation has been obtained that allows, without resorting to the grapho-analytical method, to calculate the change in the characteristics of the pump with a proportional change in all its dimensions and a constant frequency of rotation and the equation of the curve of similar modes. This curve is proposed to be called the similarity curve. It is shown that the velocity coefficient is a constant value along the polynomial curve. On the basis of the obtained results, a method of comparative analysis of the energy efficiency of the regulation of the pumping unit by changing the rotation frequency and proportionally changing all dimensions of the impeller is proposed. The application of the method is demonstrated on concrete examples. Achieving the highest efficiency of the pumping unit ensures the lowest energy consumption, thus minimizing emissions of harmful substances into the atmosphere.