Optimum control of temperature and flow of the heating agent in heating networks with variable efficiency of pumps

The problem of energy saving in the housing and communal sector is currently very urgent. The solution to this problem is possible, first of all, through the development and implementation in automation systems of optimal algorithms for controlling heating and heat supply processes in general. The problem of the choice of the temperature and flow rate of the heat carrier according to the criterion of the minimum consumption of electrical energy for pumping and the reduction of heat losses during its transportation along heat pipelines is considered. When solving the problem, the characteristics of heat-consuming equipment and the value of heat that is actually necessary to maintain the required temperature of the microclimate of buildings are taken into account. It is also considered that the efficiency of network pumps depends on the supply - flow rate of the pumped medium, and the heat supply object is represented as an equivalent heating device. This problem is a conditional optimization problem with two arguments. The solution of the problem leads to the need to find the roots of the complete algebraic equation of the fourth degree; to do this, well-known online calculators have been used in this work. The data for calculating the optimal temperature and flow rate for specific conditions are given. Numerical studies have confirmed that at the extreme points used in the work a local minimum of the optimization criterion is actually achieved. Methods for determining the parameters of a heating device, which is the calculated equivalent of the heat-consuming equipment of the object, are indicated, both in terms of operational and calculated data used in the design of the heat supply system. It has been established that in heat networks it is necessary to apply qualitative and quantitative regulation of the heat supply process, i.e. when the outside temperature changes, it is necessary to change not only the temperature of the coolant, but also its consumption. To the point, it should be emphasized that at present, in the overwhelming majority of cases, a qualitative method of regulating the heat supply process is used. The results obtained can be used as part of the algorithmic support of modern heat supply control systems.