지중열 교환기와 빙축열조(Thermal Ice Storage)를 연계시킨 통합 지중열

ED. Lohrenz,한정상(Jeongsang Hahn),한혁상(Hyuk Sang Han),한찬(Chan Hahn),김형수(Hyoung Soo Kim) 대한자원환경지질학회 2005 자원환경지질 Vol.38 No.6

일반적으로 대규모 건물의 피크 냉방 부하는 난방부하보다 크다. 북위도의 한냉한 지역에 소재한 대규모건물의 냉난방 설비는 건물 내부에서 생성되는 발열량과 태양으로부터 획득되는 열량에 따라 좌우된다. 최대 냉방부하에 적합하도록 냉난방설비와 지중루프를 설치하는데 소요되는 비용은 일반적으로 초기투자비가 적게 드는 전통적인 HVAC시스템에 비해 다소 고가이다. 빙축열조(Thermal ice storage, TES)시스템은 과거 수년동안 일반 HVAC에서 냉동기의 용량을 축소시키거나 최대 전력부하 시간대를 바꾸기 위해 사용되어온 기술이다. 일반적으로 건물 난방을 위해서는 보일러와 같은 전통적인 난방설비를 이용하고 그 다음날의 건물냉방을 위해서는 전력료가 저렴한 야간에 빙축을 시키는 빙축열기법을 이용한다. 얼음에서 추출한 잠열 에너지의 장점을 이용하기 위해 설계된 분배시스템(distribution system)과 열원과 열배출원(열침, sink)대신에 지중열 교환기(지중루프)를 이용하면 많은 장점이 있다. 공간 난방과 급탕을 공급하기위한 분리형 설비를 별도로 사용하지 않아도 된다. 공간난방용으로 소요되는 설비용량을 축소시킬 수있으며-소요 지중열 교환기의 규격과 비용을 절감시킴은 물론 지열 HVAC시스템의 효율을 배가 시킬 수 있으며 온실가스 배출량을 대폭 감축시킬 수 있다. 또한 TES를 적용하면 대규모 건물의 냉난방부하와 열펌프의 용량을 40∼60%정도 감축시킬수 있으며 설비대수와 기계실 공간을 줄일수 있다. 뿐만아니라 피크 냉난방부하를 토대로 설계한 지원열펌프 시스템(Ground source heat pump system)의 지중루프를 1/4∼1/3까지 줄일수 있어 도심지역에서 지중루프를 설치할 때 장애요인인 지중루프 설치공간문제와 지중암석의 열적특성문제를 동시에 해결할수 있다. Peak cooling load of large buildings is generally greater than their peak heating load. Internal and solar heat gains are used for selection of adquate equipment in large building in cold winter climate like Canada and even Korea. The cost of geothermal heat exchanger to meet the cooling loads can increase the initial cost of ground source heat pump system to the extend less costly conventional system often chosen. Thermal ice storage system has been used for many years in Korea to reduce chiller capacity and shift peak electrical time and demand. A distribution system designed to take advantage of heat extracted from the ice, and use of geothermal loop (geothermal heat exchanger) to heat as an alternate heat source and sink is well known to provide many benifits. The use of thermal energy storage (TES) reduces the heat pump capacity and peak cooling load needed in large building by as much as 40 to 60% with less mechanical equipment and less space for mechanical room. Additionally TES can reduce the size and cost of the geothermal loop by 1/3 to 1/4 compared to ground coupled heat pump system that is designed to meet the peak heating and cooling load and also can eliminate difficuties of geothermal loop installation such as space requirements and thermal conditions of soil and rock at the urban area.

Design of Supervisory Model Predictive Control for Building HVAC System with Time-Varying Coefficient of Performance

Chanthawit Anuntasethakul,Kantapong Leungrungwason,David Banjerdpongchai 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

This paper presents a design of supervisory model predictive control (SMPC) for a building heating-ventilation-air-conditioning (HVAC) system. The control objectives are to minimize the total operating cost (TOC) and the thermal comfort cost (TCC). According to practical realization, a coefficient of performance (COP) is a time-varying parameter of HVAC system and depends on environment conditions. Therefore, we employ an artificial neural network (ANN) with k-means clustering to predict the COP. We design the SMPC to determine the optimal set-point temperature for the HVAC system which serves our control objectives. We utilize the predicted mean vote (PMV) to handle thermal comfort of occupants and to indicate an acceptable bound of the optimal set-point temperature. We formulate the SMPC with the predicted COP integration as two quadratic programs. The first quadratic program is a supervisory control problem for optimal set-point searching problem and the other is an MPC problem for optimal control input searching problem. Our results reveal that the root-mean-square error (RMSE) of the predicted COP is reduced by 34% using the clustered-ANN. When the SMPC is applied to the time-varying HVAC system, the TOC decreases by 14.53% compared to that of the nominal operation. Moreover, the maximum electrical power of the HVAC system is reduced by 15.66% resulting from smoothly shaved electrical power profile.

건물의 냉, 난방 부하비율과 HVAC&R 시스템 1차 에너지 소비량의 상관관계분석 및 합리적 설계방안 연구

조진균(Jinkyun Cho),김진호(Jinho Kim),이성재(Suengjae Lee),강호석(Hosuk Kang) 대한설비공학회 2015 설비공학 논문집 Vol.27 No.3

HVAC&R systems account for more than 50% of the energy consumption of buildings. The purpose of this study is to propose an optimal design method for the HVAC&R system and to examine the possibility for the energy conservation of a selected system. The energy demand for cooling and heating is determined by using TRNSYS and HEET. By an interaction between total system efficiency and cooling-to-heating load ratio, the optimal HVAC&R systems will be decided. The results showed that this proposed method is significantly capable of determining optimal system and building design for saving energy.

사무소 건물 HVAC&R 시스템의 에너지 효율화 사례연구

조진균(Cho, Jin-Kyun),우경헌(Woo, Kyung-Hun),박우평(Park, Woo-Pyoung),신승호(Shin, Seung-Ho) 한국지열·수열에너지학회 2013 한국지열에너지학회논문집 Vol.9 No.1

HVAC&R systems are the most energy consuming building services representing approximately half of the final energy use in the building sector. Despite their significant energy use, there is a lack of a consistent and homogeneous framework to efficiently guide research, mainly due to the complexity and variety of HVAC&R systems but also to insufficient rigour in their energy analysis. This research reviews energy consumption of HVAC&R systems with the aim of establishing a common idea for the analysis of energy efficiency. The paper focuses on energy flow of the HVAC&R which include air-conditioning, transport and heat generation system for low-energy buildings.

주거용 건물에 대한 공기열원 Heat pump와 전열교환기가 융복합된 HVAC 시스템의 난방 에너지성능 비교 분석

최민호(Choi Minho),이광호(Lee Kwangho) 한국태양에너지학회 2022 한국태양에너지학회 논문집 Vol.42 No.6

The purpose of this study is to compare the energy performance of a convergence high-efficiency HVAC module developed for application to residential buildings. The developed HVAC module is a system that combines a heat pump and an energy recovery ventilation system (ERV). The developed system is designed to recover energy using the ERV and heat-exchanged air passing through the heat exchanger of the heat pump. The study was conducted in a demonstration-house test building located at the LHI Housing Performance Research and Development Center. General equipment (cooling, heating, ventilation) was installed based on the common area of the demonstration house and compared with the condition of maintaining the same indoor temperature and humidity relative to the outdoor temperature in winter. The test results showed that, compared to the general equipment, the convergence HVAC module consumed less power, while maintaining a comfortable indoor environment. It consumed approximately 33% less electricity compared to the general equipment.

자동차 실내 IAQ향상을 위한 HVAC 내외기율 범위에 따른 수치 해석적 연구

서진원(Jinwon Seo),최윤호(Yunho Choi),임택규(Taekkyu Lim),조중원(Chungwon Cho),박지용(Jiyong Park),김만회(Manhoe Kim) 한국자동차공학회 2011 한국자동차공학회 학술대회 및 전시회 Vol.2011 No.11

The air quality inside the cabin of an automobile is closely related to the health of those who spend a lot of time in their vehicles. Automotive indoor air quality can be improved in several ways; the most common and effective of which was to dilute the polluted air with fresh air through the vehicle"s HVAC. In this study, we considered switching between the outside air mode and the recirculation mode of the automotive HVAC, and how that change affected the concentration of pollution within the vehicle. The possible range between the outside air mode and the recirculation mode of the vehicle"s HVAC obtained by this experiment was applied to the CFD analysis. Furthermore, the actual vehicles were infused with gas over time and were compared for the purposes of feasibility review of numerical simulation and concentration trends of experimental data. In the CFD analysis, UDF(user defined function) was applied to our code in order to decipher the range of outside air and recirculation mode of the HVAC. Data generated through the full range between outside air and recirculation mode of the vehicle"s HVAC were analyzed under a variety of conditions which allowed the identification of characteristics which changed indoor air quality source concentration.

Analysis of HVAC-linked Bio-filter Technology and Construction Case Studies

Kim, Cheolmin(김철민),Kim, Taehan(김태한),Lee, Sodam(이소담),Park, Junghyun(박정현) 한국태양에너지학회 2016 한국태양에너지학회 학술대회논문집 Vol.2016 No.10

분산전원이 연계된 제습 HVAC 시스템의 성능해석 연구

정융(Yoong Jung),류진우(Jin Woo Yoo),김민수(Min Soo Kim) 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.2015 No.11

A hybrid heat pump - desiccant rotor HVAC system coupled to decentralized cogenerator is proposed. Despite high total energy efficiency of micro - CCHP system, there still exist substantial dependence on purchased electricity and extra boiling which reduces the advantages of CCHP system. To solve the problem, air to water heat pump is adopted to intensifying desiccant HVAC system. A mathematical system model including air to water heat pump, desiccant cooling system, PEMFC for cogeneration is devised to investigate the characteristics and performance of desiccant cooling system and heat pump water heating/cooling system. Based on the calculation results, optimal operational condition and system efficiency according the ambient condition is proposed.

모듈러 건축의 히트펌프 기반 에너지 절약 요소기술 및 사례

이재용(Jae Yong Lee),권민호(Min Ho Kwon),강윤태(Youn Tai Kang) 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.11

NUMERICAL STUDY TO EVALUATE THE CHARACTERISTICS OF HVAC-RELATED PARAMETERS TO REDUCE CO2 CONCENTRATIONS IN CARS

S. H. YOON,H. S. AHN,Y. H. CHOI 한국자동차공학회 2016 International journal of automotive technology Vol.17 No.6

Today, as people are spending increasing amounts of time in their cars, they have come to recognize that the car should function as a “residential” space. An eco-friendly indoor environment that provides comfort in terms of visual, tactile, and auditory senses is needed for the driver and the passengers. The quality of the car’s indoor environment was evaluated on various factors, such as indoor thermal comfort, indoor air quality, smell, and noise. For the indoor air quality, the typical pollutants that degrade the air quality are CO2, volatile organic compounds, and exhaust gases. Especially, CO2 has a direct relationship with drowsy driving which leads to traffic accidents. There have been many experimental and analytical studies to reduce the level of CO2 in a short time, but analyses of parameters that affect indoor CO2 concentration are insufficient and comprehensive standards for evaluating the car indoor CO2 concentration do not yet exist. In this study, several parameters were selected that can influence the reduction rate of CO2 concentration, and a series of computational analyses were conducted to study the results of these parameters in CO2 reduction. Based on this study, a prediction equation for CO2 concentration was derived. For this, a general full factorial design was used to evaluate the CO2 reduction characteristic based on various parameters (ventilation mode, boarding condition, vent angle, mass flow rate, and operation mode), and then their effects were analyzed to obtain an evaluation database of indoor air quality. From that, a prediction equation was derived to estimate the indoor air quality, enabling us to evaluate the CO2 concentration quickly that actually influences the human body without carrying out time-consuming CFD analyses for CO2 concentration. This study will be useful in designing HVAC systems and establishing the control logic for effective improvement of the car’s indoor air quality in the future.