• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.197.2-197.2
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• 2010

The study on the operation characteristics of solar space and water heating system with ground source heat pump (GSHP) as a back-up device was carried out. This system, called solar thermal and geothermal hybrid system (ST/G), was installed at Zero Energy Solar House II (KIER ZeSH-II) in Korea Institute of Energy Research. This ST/G hybrid system was developed to supply all thermal load in a house by renewable energy. The purpose of this study is to find out that this system is optimized and operated normally for the heating load of ZeSH-II. Experiment was continued for seven months, from October to April. The analysis was conducted as followings ; - the contribution of solar thermal system. - the appropriateness of GSHP as a back-up device. - the performance of solar thermal and ground source heat pump system respectively. - the adaptation of thermal peak load - the operation characteristics of hybrid system under different weather conditions. Finally the complementary measures for the system simplification was referred for the commercialization of this hybrid system.

• 한국산학기술학회논문지
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• 제14권12호
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• pp.6053-6059
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• 2013

히트 펌프는 지열이나 태양열 등의 신재생 에너지를 이용하거나 기타 폐열을 재활용하여 기존의 전기 히팅 난방 시스템들보다 에너지 소비율을 낮출 수 있다는 장점으로 인해 그린 에너지 시스템으로써 주목을 받아 왔다. 고효율 히트펌프 시스템 설계를 위한 연구는 오랫동안 지속되어 왔지만, 각각의 구성요소가 유기적이며, 변화에 유연한 해석모델은 존재하지 않는다. 따라서 본 연구에서는 공기 열 원식 히트 펌프를 AMESim Software를 이용해 구성하였다. 독자적으로 개발한 스크롤 압축기 해석 모델을 히트펌프 시스템에 조합함으로써 효율 향상 방안을 모색하였으며, 실험 데이터를 이용하여 개발한 해석모델을 검증하였다. 실험 데이터와 개발한 해석 모델을 이용하여 예측된 데이터를 비교한 결과 최대 오차가 10% 이내로 두 데이터가 잘 일치하였다. 본 연구에서 개발한 히트펌프 해석모델은 향후 시제품을 개발하고 효율 향상을 위한 연구 등에 유용하게 사용될 것으로 사료된다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회B
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• pp.2017-2022
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• 2008

The crude oil pump system is the equipment for transporting crude oil and it consists of 3 major components, a motor and an impeller which discharge underground crude oil, a pipestack that transmits the cooling oil and power, and a cooling oil unit & junction box that provides cooling oil and electric power. When considering the system characteristics that it has to be installed at a depth of deeper than 100 m, a design technology for the efficient control of the heat occurring at a conductor and motor is necessary and it is the essential factor for ensuring system durability. In this paper, therefore, cooling oil flow has been calculated to satisfy the limit value of the system temperature by analyzing heat flow considering the related losses such as loss of conductor, contact resistor loss at the conductor connection, and operation loss of motor. And the operation temperature has been set up based on the temperature of crude oil and the heat of motor and conductor. Also, a design for cooling of crude oil pump system has been proposed by calculating the operation pressure loss and selecting the capacity of a cooling oil pump and a heat exchanger.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.299-303
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• 2008

The treated sewage temperature is about $5^{\circ}C$ lower in summer and $5{\sim}10^{\circ}C$ higher in winter than ambient air. It can be used heat pump heat source and is good heat source on high performance of heat pump. In this study, to develop 100RT 2-stage compression heat pump use treated sewage water heat source and system applies to sewage disposal plant. Although heat pump is better performance, the large temperature difference between load and source makes the performance degradation of a heat pump. To solve this problem screw 2-stage compression is considered. The experiment was focused on the system operating performance variations over supply water and treated sewage water a temperature in the field. The results show that system of heating performance is higher then general heat pump and is enough to supply a hot water of $70^{\circ}C$.

• 한국태양에너지학회 논문집
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• 제34권3호
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• pp.75-81
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• 2014

Recently, the use of renewable energy has been attracted due to the interest in energy-saving and the reduction of CO2 emission. In order to reduce the energy consumption of the cooling and the heating in the field of the architectural engineering, heat pump systems using renewable energy have been developed and used in various applications. In many researches, integrated heat pump systems are suggested which use solar and geothermal heat as the heat source for cooling and heating. However, it is still difficult to predict the performance of the systems, because the characteristic of heat exchange in each system is complicated and various. In this system, the performance prediction simulation of the heat pump was developed using a dynamic simulation model. This paper describes the summary of the suggested systems and the result of the simulation. The average temperature of the heat source, heating loads and COP were calculated with the cases of different local conditions, different system composition and different operation time by TRNSYS 17.

• 설비공학논문집
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• 제25권8호
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• pp.443-449
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• 2013

The purpose of this study is to propose an enhanced variable-speed control method of ground-water circulation pumps using inlet and outlet ground-water temperature difference and analyze its effect for the ground source multi-heat pump system installed in a single-family house. As a result, it has shown to significantly reduce the electricity use of ground-water circulation pump and improve overall system Coefficient of Performance (COP) due to the proposed variable-speed control under partial load conditions after oversized and inefficient single-speed pump retrofit.

• 신재생에너지
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• 제19권4호
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• pp.72-83
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• 2023

Only ground source heat pump units certified according to the regulations in Korea can be adopted in ground source heat pump systems. In this study, domestic and international standards and regulations for ground source heat pump units were investigated. Unlike ISO 13256-1~2, which is the international standard, KS B 8292~8294 for ground source heat pump unit only included rated test conditions. Therefore, it is necessary to supplement various test conditions to the KS B series, because its performance data, which is required to calculate the system's design capacity, is dependent on the change in entering water temperature. The difference between the coefficient of performance of the certified ground source heat pump units and the certified criteria changed significantly according to the operating mode, heat source, and load type, because the criteria increased by about 5% for all. Thus, it is highly suggested that the certification standards be revised while considering the product performance level and various conditions.

• 생물환경조절학회지
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• 제21권4호
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• pp.372-378
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• 2012

본 연구에서는 화력발전소에서 온배수의 형태로 배출되는 폐열을 히트펌프의 열원으로 이용하여 온실의 난방에 활용할 수 있는 히트펌프 시스템을 설계 제작하였으며, 난방 성능을 분석하여 PE 파이프 열교환기의 설계기준을 제시하고자 하였다. PE 파이프 열교환기의 내경은 20mm, 두께는 2mm였으며, Roll의 직경은 1,000mm로 하였다. 연구결과 PE파이프 열교환기의 적정 길이는 1.0RT당 75m로 설계하는 것이 바람직할 것으로 판단되었으며, 이때 히트펌프시스템의 난방성능계수(COPh)는 3.8로 나타났다.

• 설비공학논문집
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• 제2권3호
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• pp.218-225
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• 1990

Studies on the performance of a heat pump using non-azeotropic refrigerant mixtures are done. In order to estimate the thermodynamic properties for the selected non-azeotropic refrigerant mixtures including R22/R152a, R22/R142b, R22/R114 and R13B1/R152a, Peng-Robinson equation of state is adopted. The pressure-enthalpy diagram and the temperature-entropy diagram are plotted for each refrigerant mixture. Considerations on the capacity modulation for the heat pump system using refrigerant mixtures are taken into. Results show that when the heating load varies, the possibility for the capacity modulation is found in the heat pump system using a compressor with constant volume flow rate. Under a constant heating capacity condition in the heat pump system, the coefficient of performance increases when the refrigerant mixtures are used. The volume flow rate decreases as the mass fraction of lower boiler increases in this case.

• 한국지열·수열에너지학회논문집
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• 제9권2호
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• pp.16-24
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• 2013

A multi-heat pump provides the benefits of comfort, energy conservation and easy maintenance. Recently, the multi-heat pump has been widely employed in small and medium-sized buildings. However, the control algorithm of the multi-heat pump are limited in the open literature due to complicated operating conditions. In this study, the MIMO control algorithm using integral optimum regulator was designed and the control performance of it was analyzed. In addition, system model of the control plant was developed by PRBS system identification scheme. The MIMO controller adopting the integral optimum regulator yielded satisfactory control performance results.