scholarly journals OPERATION ANALYSIS OF THE AIR-SOURCE HEAT PUMP USING TRNSYS SIMULATION TOOL

2021 ◽  
Vol 13 (0) ◽  
pp. 1-6
Author(s):  
Gabrielė Daugirdaitė ◽  
Giedrė Streckienė ◽  
Tomas Kropas
Keyword(s):  
Heat Pump ◽  
Real Data ◽  
Cold Season ◽  
Heat Pumps ◽  
Climatic Data ◽  
Pump Operation ◽  
Operation Analysis ◽  
Air Source Heat Pump ◽  
Heating Capacity ◽  
Heating Mode

In order to achieve ambitious goals for energy efficiency and requirements for near zero energy buildings, various technological solutions enabling the use of renewable energy are proposed and applied. One such rapidly spreading technology is heat pumps. However, the use of air-­to-­water heat pumps in countries where the cold season is cold and humid has unfavourable conditions for the operation of this equipment during the heating season. As a result, the performance efficiency of the equipment decreases. This article presents the simulation results of an air-­to-­water heat pump operation in Lithuania using the TRNSYS modelling tool; its nominal heating capacity is 6.55 kW. The model was calibrated using real data obtained at Vilnius Gediminas Technical University when measurements were performed under heat pump freezing conditions. The seasonal performance factor of the heat pump heating mode was determined during the calculation. Parametric analysis of the model was also performed, when sensitivity of the model to the initial climatic data was observed. Comparable results are obtained for Vilnius, Prague and London.

scholarly journals EXPERIMENTAL INVESTIGATION OF AIR-SOURCE HEAT PUMP IN DIFFERENT REAL OPERATIONAL CONDITIONS FOR HEATING DISTINCTIVE REGIMES

2020 ◽  
pp. 087
Author(s):  
Goran Vuckovic ◽  
Mića Vukić ◽  
Mirko Stojiljković ◽  
Marko Ignjatović
Keyword(s):  
Low Temperature ◽  
Heat Pump ◽  
Operating Conditions ◽  
Hot Water ◽  
Maximum Temperature ◽  
Water Heating ◽  
Pump Operation ◽  
Domestic Hot Water ◽  
Air Source Heat Pump ◽  
Heating Mode

In a time of permanent care for environmental protection, energy consumption and conservation of resources, heat pumps are becoming increasingly important as a technology for reducing greenhouse gas emissions while preservation thermal comfort in build environment. This paper presents the experimental results of air-source heat pump in different real operating conditions, as follows: for space heating by low-temperature underfloor heating when the supply water temperature was set at 38°C, or for domestic hot water heating in the storage tank volume of 180 liters at a temperature of 46°C. In the low-temperature underfloor heating mode, the efficiency of the air-source heat pump could be increased if the maximum temperature at the end of the compression process and the condensing temperature were reduced in the initial phase of the heat pump operation. In the domestic hot water heating mode, the efficiency of the air-source heat pump could be increased if the maximum condensation temperature in the final phase of the heat pump operation was limited.

scholarly journals Energy Saving Potential of Radiant Floor Heating Assisted by an Air Source Heat Pump in Residential Buildings

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1321
Author(s):  
Yu-Jin Hwang ◽  
Jae-Weon Jeong
Keyword(s):  
Energy Saving ◽  
Heat Pump ◽  
Residential Buildings ◽  
Heating Systems ◽  
Air Source Heat Pump ◽  
Heating Capacity ◽  
Heating Loads ◽  
Radiant Floor Heating ◽  
Floor Heating ◽  
Floor Temperature

The objective of this research is to establish an appropriate operating strategy for a radiant floor heating system that additionally has an air source heat pump for providing convective air heating separately, leading to heating energy saving and thermal comfort in residential buildings. To determine the appropriate optimal operating ratio of each system taking charge of combined heating systems, the energy consumption of the entire system was drawn, and the adaptive floor surface temperature was reviewed based on international standards and literature on thermal comfort. For processing heating loads with radiant floor heating and air source heating systems, the heating capacity of radiant floor heating by 1 °C variation in floor temperature was calculated, and the remaining heating load was handled by the heating capacity of the convective air heating heat pump. Consequently, when the floor temperature was 25 °C, all heating loads were removed by radiant floor heating only. When handling all heating loads with the heat pump, 59.2% less energy was used compared with radiant floor heating only. Considering the local discomfort of the soles of the feet, the floor temperature is expected to be suitable at 22–23 °C, and 31.5–37.6% energy saving compared with those of radiant floor heating alone were confirmed.

scholarly journals Experiment Study on Performance of Air Source Heat Pump

2013 ◽  
Vol 805-806 ◽  
pp. 645-648
Author(s):  
Wei Xiu Shi ◽  
Li Sheng Pan
Keyword(s):  
Heat Pump ◽  
Temperature Difference ◽  
Heat Pumps ◽  
Outlet Temperature ◽  
Exhaust Temperature ◽  
Air Source Heat Pump ◽  
And Performance ◽  
Save Energy ◽  
C 30 ◽  
Set Up

Under the situation of energy crisis, air source heat pumps are paid more attention recently. In order to save energy, the feasibility and performance of air source heat pump are studied by experiment, and variation laws of exhaust temperature, evaporator outlet temperature and outlet presser of compressor were analyzed in this paper. Air source heat pump apparatus were set up and the experiment was during 10°C, 20°C, 30°C and 40°C. The results were as follows: exhaust temperature of compressor increases gradually with the increase of tank temperature, but the temperature difference between exhaust temperature of compressor and tank temperature becomes little; temperature difference in evaporator decreases; Compressor outlet pressure increases obviously.

scholarly journals Performance analysis of a two-stage variable capacity air source heat pump and a horizontal loop coupled ground source heat pump system

2021 ◽  
Author(s):  
Amir Alizadeh Safa
Keyword(s):  
Heat Pump ◽  
Ground Source Heat Pump ◽  
Outdoor Temperature ◽  
Cooling Mode ◽  
Two Stage ◽  
Pump System ◽  
Air Source Heat Pump ◽  
Ground Source ◽  
Variable Capacity ◽  
Heating Mode

The thermal performance of a new two-stage variable capacity air source heat pump (ASHP) and a horizontal ground loop ground source heat pump (GSHP) was investigated side-by-side at the Archetype Sustainable Twin Houses located in Toronto, Canada. The heat pumps were tested in cooling mode, as well as heating mode under extreme winter conditions. In cooling mode, the ASHP COP ranged from 4.7 to 5.7 at an outdoor temperature of 33 degrees C and 16 degrees C respectively, while the GSHP COP ranged from 4.9 (at an ELT of 8.5 degrees C and EST of 19.2 degrees C) to 5.6 (at an ELT of 12. 4 degrees C and EST of 17.8 degrees C). In heating mode, the ASHP COP ranged from 1.79 to 5.0 at an outdoor temperature of -19 degrees C and 9 degrees C respectively, while the GSHP COP ranged from 3.05 (at an ELT of 44.4 degrees C and an EST of 2.7 degrees C) to 3.44 (at an ELT of 41.5 degrees C and an EST of 5.48 degrees C) during the earlier winter test period. Data extrapolation and energy simulation was also performed to predict annual heat pump performance in Toronto as well as other Canadian regions.

scholarly journals Ground-Source Heat Pumps with Horizontal Heat Exchangers for Space Cooling in the Hot Tropical Climate of Thailand

Energies ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1274 ◽  
Author(s):  
Arif Widiatmojo ◽  
Sasimook Chokchai ◽  
Isao Takashima ◽  
Yohei Uchida ◽  
Kasumi Yasukawa ◽  
...  
Keyword(s):  
Economic Growth ◽  
Heat Pump ◽  
Heat Exchangers ◽  
Life Cycle Cost ◽  
Heat Pumps ◽  
Ground Source Heat Pump ◽  
Ground Source Heat Pumps ◽  
Air Source Heat Pump ◽  
Ground Source ◽  
Space Cooling

The cooling of spaces in tropical regions, such as Southeast Asia, consumes a lot of energy. Additionally, rapid population and economic growth are resulting in an increasing demand for space cooling. The ground-source heat pump has been proven a reliable, cost-effective, safe, and environmentally-friendly alternative for cooling and heating spaces in various countries. In tropical countries, the presumption that the ground-source heat pump may not provide better thermal performance than the normal air-source heat pump arises because the difference between ground and atmospheric temperatures is essentially low. This paper reports the potential use of a ground-source heat pump with horizontal heat exchangers in a tropical country—Thailand. Daily operational data of two ground-source heat pumps and an air-source heat pump during a two-month operation are analyzed and compared. Life cycle cost analysis and CO2 emission estimation are adopted to evaluate the economic value of ground-source heat pump investment and potential CO2 reduction through the use of ground-source heat pumps, in comparison with the case for air-source heat pumps. It was found that the ground-source heat pumps consume 17.1% and 18.4% less electricity than the air-source heat pump during this period. Local production of heat pumps and heat exchangers, as well as rapid regional economic growth, can be positive factors for future ground-source heat pump application, not only in Thailand but also southeast Asian countries.

scholarly journals A Study on the Performance of a Cascade Heat Pump for Generating Hot Water

Energies ◽  
2019 ◽  
Vol 12 (22) ◽  
pp. 4313 ◽  
Author(s):  
Boahen ◽  
Choi
Keyword(s):  
Heat Exchanger ◽  
Energy Saving ◽  
Heat Pump ◽  
Heat Pumps ◽  
Hot Water ◽  
Research Interest ◽  
Coefficient Of Performance ◽  
Energy Saving Potential ◽  
Heating Capacity

The use of cascade heat pumps for hot water generation has gained much attention in recent times. The big question that has attracted much research interest is how to enhance the performance and energy saving potential of these cascade heat pumps. This study therefore proposed a new cycle to enhance performance of the cascade heat pump by adopting an auxiliary heat exchanger (AHX) in desuperheater, heater and parallel positions at the low stage (LS) side. The new cascade cycle with AHX in desuperheater position was found to have better performance than that with AHX at heater and parallel positions. Compared to the conventional cycle, heating capacity and coefficient of performance (COP) of the new cascade cycle with AHX in desuperheater position increased up to 7.4% and 14.9% respectively.

Study of Performance of Attic Air Source Heat Pump in Maine

2014 ◽  
Author(s):  
Lin Lin ◽  
Julie Doxsey
Keyword(s):  
Heat Pump ◽  
Operating Performance ◽  
Experimental Tests ◽  
The United States ◽  
Heat Pumps ◽  
Water Tank ◽  
Heating Source ◽  
Air Source Heat Pump ◽  
Testing Chamber ◽  
Heat Released

Heat pumps are a popular heating source in many parts of the United States. They are not widely used in State of Maine due to an assumption that they are marginally useful in cold climates. An attic source heat pump is a variation on a conventional heat pump. In summer, the temperature in the attic is much higher than outside as it absorbs the heat from sunlight. In winter or evening, the attic captures the heat released from the house. Therefore, the attic makes a good candidate for the heat source of a heat pump. For this ongoing study, a laboratory scale heat pump was constructed and experimental tests were performed to establish its operating performance. A temperature controlled testing chamber was built to simulate the attic environment. Attic heat was used to heat up a water tank. COP value was measured for different attic temperatures. Experimental data were favorable to the use of an attic air source heat pump in Maine.

scholarly journals Seasonal coefficient of performance of air-to-air heat pump and energy performance of a building in Poland

2019 ◽  
Vol 116 ◽  
pp. 00039 ◽  
Author(s):  
Piotr Kowalski ◽  
Paweł Szałański
Keyword(s):  
Heat Pump ◽  
Energy Performance ◽  
Heat Pumps ◽  
Climatic Conditions ◽  
Coefficient Of Performance ◽  
Climatic Data ◽  
Heating Season ◽  
Season Length ◽  
Local Climate ◽  
Significant Difference

The article discusses the problem of determining for air heat pumps the seasonal efficiency of energy production necessary to determine the energy performance of a building. On the example of selected Polish cities (Suwalki, Bialystok, Warsaw, Wroclaw, Zielona Gora, Resko, Szczecinek, Koszalin) the influence of climatic conditions on the SCOP of an exemplary air-to-air heat pump and on the result of building energy performance calculations was analysed. SCOPs for each location were determined according to the method of EN 14825. The difference between SCOP for average (A) and colder (C) climates according to EN 14825 was 35.6%. It has been shown that the climate of Polish cities may be similar to both the average climate (A) and the colder climate (C), or they significantly differ from both climates. The most significant difference in SCOP between the analysed cities was obtained for Suwalki and Szczecinek. It was 31.9% and 31.4% for the assumed heating season length as for climate (A) and (C) respectively. For the exemplary building in Suwalki, taking SCOP for the average climate (A) and not based on climatic data of Suwalki gives an error of 39.3% in the calculation of primary energy for heating. For the same locations, the differences in SCOP and EP resulting from the assumption of the heating season length as for the average climate (A) or as for the colder climate (C) were respectively from 2.4% to 3.3% and from -3.4% to -2.2%. In diversified Polish climate, assuming the same SCOP values of air heat pumps regardless of location does not allow for their full comparison with devices whose efficiency does not depend on climatic conditions. The authors suggest that when calculating the energy performance of the building, the SCOP should be always determined on the basis of the local climate and the length of the heating season.

scholarly journals The modelling of reverse defrosting cycles of air-to-water heat pumps with TRNSYS

2019 ◽  
Vol 111 ◽  
pp. 01063 ◽  
Author(s):  
Matteo Dongellini ◽  
Agostino Piazzi ◽  
Filippo De Biagi ◽  
Gian Luca Morini
Keyword(s):  
Heat Pump ◽  
Operating Mode ◽  
Heat Pumps ◽  
Climatic Conditions ◽  
Performance Data ◽  
Energy Losses ◽  
Heating Season ◽  
Indoor Thermal Comfort ◽  
Reverse Mode ◽  
Heating Capacity

The most widespread defrosting technique adopted by Air-Source Heat Pumps (ASHPs) during the heating season is Reverse Cycle Defrosting (RCD). In this paper a dynamic model of RCD, based on performance data provided by the heat pump manufacturer, designed for TRNSYS and with a core-structure suitable for commercial units, is presented. A defrost cycle is divided in three phases. First, the unit heating capacity is reduced as a linear function of the ice layer thickness (Pre-Defrost phase). Subsequently, the reverse cycle operating mode is modelled on the basis of the performance data given by the manufacturer (Defrost phase) and, finally, the heat pump performances are altered taking into account the higher surface temperature of the external coil after the reverse mode (Post-Defrost phase). Then, the influence of defrosting energy losses on the heat pump seasonal performance factor in sites characterized by different climatic conditions has been assessed. Results point out that the ASHP seasonal efficiency decreases of about 5% taking into account defrost energy losses; in addition, the influence of defrost cycles on the internal air temperature is studied by assessing under which conditions the indoor thermal comfort can be guaranteed even in presence of frequent defrost cycles.

The Experiment Research on Applying Air Source Heat Pump in Boiled Water Machine

2011 ◽  
Vol 383-390 ◽  
pp. 1933-1937
Author(s):  
Wei Xiu Shi ◽  
Wei Yi Li ◽  
Li Sheng Pan ◽  
Zhi Hua Zhou
Keyword(s):  
Energy Saving ◽  
Heat Pump ◽  
Heat Pumps ◽  
Outlet Temperature ◽  
Experiment Research ◽  
Heating Method ◽  
Air Source Heat Pump ◽  
And Performance ◽  
Saving Effect ◽  
Boiled Water

Under the situation of energy crisis, air source heat pumps are paid more attention recently. In terms of energy saving, the feasibility and performance of boiled water machine with air source heat pump are studied by experiment in this paper. The results are as follows: the best outlet temperature of heat pump is 55°C in winter, and that is 65°C in other seasons correspondingly. Electromagnetic heater is used as the accessorial heating method, which can heat water to 95°C so as to be fit to drinking. Moreover, the energy saving effect of the unit is remarkable. At the end of the paper, the preliminary conception of structure and automatic control is proposed.

Sign in / Sign up

Export Citation Format

Share Document