Mobile QR Code QR CODE : Korean Journal of Air-Conditioning and Refrigeration Engineering
Korean Journal of Air-Conditioning and Refrigeration Engineering

Korean Journal of Air-Conditioning and Refrigeration Engineering

ISO Journal TitleKorean J. Air-Cond. Refrig. Eng.
  • Open Access, Monthly
Open Access Monthly
  • ISSN : 1229-6422 (Print)
  • ISSN : 2465-7611 (Online)

Korean Journal of Air-Conditioning
and Refrigeration Engineering

A journal devoted to investigations of HVAC and building technologies in various climatic conditions

• Editors-in-Chief: Yun, Rin

긴급전환형 임시음압격리병실의 기밀성능과 형성 차압의 관계성 분석 Analysis of Airtightness Performance and Differential Pressure Relationships in Rapidly Converted Temporary Negative Pressure Isolation Rooms

Joo Yeon Roh ; Won Seok Lee ; Se Jin Lee ; Myoung Souk Yeo

This study investigates the connection between airtightness performance and differential pressure when converting general hospital wards into temporary negative pressure isolation rooms using portable HEPA filter units. The CONTAM simulation model was used to analyze a specific medical facility, conducting sensitivity and uncertainty analyses to identify key factors in the building's envelope components and estimate pressure differentials after improvements. The findings show that exterior walls, plenum inner walls, room ceilings, and ward doors are crucial in establishing the initial differential pressure. By reducing leakage areas in these components, the required volume flow rate of the portable HEPA filter units can be decreased by approximately 30% to maintain the necessary pressure standards of -2.5 ㎩. This study offers vital data for the design and operation of temporary negative pressure isolation facilities, emphasizing the need for further comprehensive evaluations.

ECO2 프로그램에서 건물 용도프로필이 에너지 성능 분석 결과에 미치는 영향 The Impact of Building Usage Profiles on Energy Performance Analysis Results In ECO2 Program

Huijing Yan ; So Min Park ; Doo Sam Song

This study examined the errors in energy performance analysis results when using a similar building's usage profile for buildings without usage profiles in the domestic building energy analysis program, ECO2. Specifically, the analysis applies the existing ECO2 profiles for elementary school classrooms when targeting facilities like daycare center classrooms, where usage profiles are missing due to recent government-led green remodeling. However, in this study, the analysis of two daycare centers (A, B) revealed significant errors of 18% and 24% respectively when compared to actual energy consumption. To address this issue, specialized usage profiles for daycare center classrooms were developed based on long-term measurements from 20 daycare centers in Gyeonggi Province. When these newly developed profiles were applied, the errors between actual energy consumption and predictions for daycare centers A and B were reduced to 13% and 6% respectively.

2030 국가 온실가스 감축 목표 달성을 위한 건물 기반 탈탄소 및 에너지 절감 핵심 기술들의 실증 연구 분석 Empirical Research Analysis of Building-based Decarbonization and Energy Reduction Core Technologies to Achieve the 2030 Nationally Determined Contributions

Seung Hwan Park ; Hyery Shin ; Gyoung Seok Choi ; Yu Min Kim

This study analyzed national R&D projects to gain insights into the present state of core technologies and practical implementation strategies. In the field of passive technology, the development of windows and exterior insulation materials plays a significant role. The average level of insulation technology stands at 0.179 W/m2K, while the average window technology level is 0.967 W/m2K. Building Energy Management Systems (BEMS) make up 32% of the active technology sector. Although there has been insufficient progress in the development of high-efficiency heat pumps, their efficiency has steadily increased from 3.1 COP in 2010 to 4.42 COP in 2023, indicating promising advancements in the future. Clean energy technologies, especially solar power, hold the largest market share, while hydrogen energy requires further technological development. Green remodeling technologies account for approximately 52% of the non-residential sector and only 3.7% of the mid-rise residential buildings sector due to various procedural and permitting issues. With recent expansion of government support from public to private buildings, green remodeling of low-rise residential buildings is rapidly on the rise. As a decarbonization strategy, there is a high demand for new renewable energy sources and the development of high-efficiency heat pump technology. Given the widespread aging of buildings in the domestic environment, green remodeling emerges as the most urgent need for enhancing building energy efficiency.

도시철도 승강장의 에너지 절약을 위한 히트펌프 기반 액체식 제습시스템의 실증 평가 Site Evaluation of a Heat Pump Based Liquid Desiccant System for Energy Saving in the Subway Platform

Chi Kwang Kim ; Jeong Soo Park ; Min Chan Park ; Jae Keun Lee ; Young Chull Ahn

The underground subway stations are open spaces that are not separated from the outside. As a result, the energy consumption for cooling is high. Therefore, it is necessary to reduce the latent heat load of the supplied air and decrease energy consumption by utilizing discarded unused energy. In this study, a heat-pump based liquid desiccant system was developed. This system can be implemented in conjunction with a turbo chiller that is already installed in an existing subway station. A demonstration system was installed at the Minam station in Busan to investigate the removal of latent heat load and the recovery rate of unused energy. The results of the demonstration facility installed at Busan Minam subway station, with the existing chiller, show a COP of 6.83, a dehumidification rate of 18.60kg/h, and a heat recovery rate of 88.9%.

R-1234ze(E) 냉매를 이용한 유하액막식 증발기 성능 실험 연구 Experimental Study on Performance of Falling Film Evaporator with R-1234ze(E)

Neul Ha ; Yoong Chung ; Jinwoo Yoo ; Sangho Sohn ; Chan Ho Song ; Jungchul Kim

Recently, the industry has witnessed a widespread development of environmentally friendly heat pump systems. These systems primarily utilize new refrigerants with a low Global Warming Potential (GWP), which tend to be more expensive. Particularly in large-scale systems, falling film evaporators have garnered increasing attention due to their ability to reduce the required amount of refrigerant compared to flooded evaporators. In this study, we investigated the performance of a falling film evaporator using one of these low GWP refrigerants, R-1234ze(E), under various operating conditions. We installed an experimental set-up for an 8 kW nominal capacity falling film evaporator. We considered three parameters as variables: inlet water temperature, inlet mass flow rate, and refrigerant saturation temperature. To determine the convective heat transfer coefficient on the refrigerant side, we employed the Wilson plot method.