Analysis of air-to-water heat pump in cold climate: comparison between experiment and simulation

Abstract

abstract. Heat pump systems are promising technologies for current and future buildings and this research presents the performance of air source heat pump (ASHP) system. The system was monitored, analysed and simulated using TRNSYS software. The experimental data were used to calibrate the simulation model of ASHP. The specific climate conditions are evaluated in the model. It was noticed for the heating mode that the coefficient of performance (COP) varied from 1.98 to 3.05 as the outdoor temperature changed from -7.0 ºC to +5.0 ºC, respectively. TRNSYS simulations were also performed to predict seasonal performance factor of the ASHP for Vilnius city. It was identified that seasonal performance prediction could be approximately 15% lower if frost formation effects are not included to air-water heat pump simulation model.

Analysis of the Advisability of Using an Air-Source Heat Pump in a Single Family House in Poland and Spain

“…However, due to the implementation of support programs, grants, credit subsidies etc., an increase in the use of heat pumps can be observed also in Poland recently. A review of heat pump systems in many different climatic regions (including cold climates) was presented in [6][7][8], while the coefficient of performance of a heating and cooling system with heat pumps was determined in [9].…”

Experimental Investigation of Frost Formation Influence on an Air Source Heat Pump Evaporator

“…It is assumed that uncertainties with direct measurements are independent, and each of them follows a normal pattern of Gaussian distribution. The measurement reliability of the COP can be expressed as the following function [30]:…”

“…Studies show that there is a need to integrate the frosting impact [26] and defrosting techniques into software [27,28]. This is especially true with very high values (>80%) of relative air humidity [29]; e.g., in cold and humid climate conditions, the deviation between models, with frost formation excluded and factored in, is~16% [30].…”

“…The dependence of the COP on the average ambient air temperature and the relative humidity was determined. This understanding of the process helps to predict and planning the operation of the ASHP better, including simulation with dynamic software, which should mirror the actual process as closely as possible [30].…”