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Determination of cop maximum of cold water loop of heat pump heating system by means of numerical-graphical optimization procedure

The paper presents the energy optimization of the cold water loop of the heat pump heating system using analytical-numerical procedure. The aim of the study is obtain the maximum COP of the heating system by optimum of the wall water mass flow rate and well pump power. The objective function is the heating system's coefficient of performance (COP). All components of the heating system: evaporator, condenser, compressor, circulation pump and well pump are described by steady-state, lumped mathematical model. The model's equations are coupled, non-linear, multivariable and algebraic the solution is feasible using an iterative numerical method. Matlab's program with Gauss elimination and Newton linearization method is applied for solving the model. The obtained numerical data are presented in 3D graphics. The optimum value of the cold-well water mass flow rate is obtained from the graphics or by using a selection algorithm. The results of the study are the adequate mathematical model for energy optimization of the heating system, the numerical algorithm for solving the model and the ultimate goal to obtain the optimum of the power of well pump and compressor.
PAPER REVISED: 2020-02-15
PAPER ACCEPTED: 2020-02-25
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