## THERMAL SCIENCE

International Scientific Journal

### AN ANALYTICAL METHOD FOR DEFINING THE PUMP`S POWER OPTIMUM OF A WATER-TO-WATER HEAT PUMP HEATING SYSTEM USING COP

**ABSTRACT**

This paper analyzes the energy efficiency of the heat pump and the complete heat pump heating system. Essentially, the maximum of the coefficient of performance of the heat pump and the heat pump heating system are investigated and determined by applying a new analytical optimization procedure. The analyzed physical system consists of the water-to-water heat pump, circulation and well pump. In the analytical optimization procedure the "first derivative equal to zero" mathematical method is applied. The objective function is the coefficient of performance of the heat pump, and the heat pump heating system. By using the analytical optimization procedure and the objective function, as the result, the local and the total energy optimum conditions with respect to the mass flow rate of hot and cold water i. e. the power of circulation or well pump are defined.

**KEYWORDS**

PAPER SUBMITTED: 2016-11-10

PAPER REVISED: 2016-12-20

PAPER ACCEPTED: 2016-12-22

PUBLISHED ONLINE: 2017-01-14

**THERMAL SCIENCE** YEAR

**2017**, VOLUME

**21**, ISSUE

**5**, PAGES [1999 - 2010]

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