Ho-Tae Seok

Measurement of Airflow around the Human Body with Wide-cover Type Personal Air-conditioning with PIV

Many existing personal air-conditioning systems cool only specific portions of the human body in the form of spot cooling, using either cooled or fast airflow to control thermal sensation. This may cause various problems related to localized airflow, such as discomfort to the face and neck areas and dryness in the eyes. Therefore, a method is proposed in this research for task area wide-cover type personal air-conditioning that prevents the task area of a human body from being exposed to a largely irregular thermal environment. A particle image velocimeter was used in the research to measure airflow fields for conventional spot cooling and wide-cover type personal air-conditioning (PAC) around the human body. The spot cooling type PAC formed an airflow of 0.3–0.6 m/s around the area of the neck. However, the wide-cover type PAC formed a calmer airflow field of less than 0.18 m s 1 around the human body. This is because the supply air from a wide-cover type PAC has a higher density than the surrounding air and can extensively cover the human body. Therefore, the wide-cover type PAC can minimize the potential for cold drafts to affect the human body.Many existing personal air-conditioning systems cool only specific portions of the human body in the form of spot cooling, using either cooled or fast airflow to control thermal sensation. This may cause various problems related to localized airflow, such as discomfort to the face and neck areas and dryness in the eyes. Therefore, a method is proposed in this research for task area wide-cover type personal air-conditioning that prevents the task area of a human body from being exposed to a largely irregular thermal environment. A particle image velocimeter was used in the research to measure airflow fields for conventional spot cooling and wide-cover type personal air-conditioning (PAC) around the human body. The spot cooling type PAC formed an airflow of 0.3–0.6m/s around the area of the neck. However, the wide-cover type PAC formed a

A Study on the Application of a Ceiling Plenum Ventilation System in an Apartment House

Currently, an air change rate (0.7 h-1) and spring cooler installation must be considered when building an apartment house in Korea, in order to comply with the Building Standards and the Fire Service Act. In accordance with a series of legal requirements for Korean apartment houses, the improvement of the availability of ceiling space and space for working ease is required in apartments by installing a new ventilation system in the ceiling space to accommodate a spring cooler. In this study, a new ventilation system is suggested, called the ceiling plenum ventilation system. To introduce this system in the residential section of a residential-commercial complex building, a constant air volume system or combination air volume system with a 150 mm supply opening and branch duct must be used. For residential-commercial complex buildings with lower ceilings or for general apartment houses, the effective area of the supply opening of the rooms and the air supply duct at the total heat exchanger side must be increased and a combination air volume system must be used.

Establishing the Design Process of Double-Skin Façade Elements through Design Parameter Analysis

Abstract The design of the double-skin façade system must consider the interactions between design parameters. The objective of this study is to propose a simple design process that considers these interactions for double-skin façades in apartment buildings in Korea. A quantitative basis was given by selecting and analyzing the design parameters related to the thermal environment. Using the Taguchi method of design of experiments, the main effects of all major design parameters and the interactions between five major parameters were revealed. The results show that the design parameters of building orientation, cavity height, cavity depth, blind position, outer skin U-value, and inner skin U-value, as well as the interaction between cavity depth and aperture size were found to be significant for total load. Based on the variance ratio of each parameter and the interactions between five parameters representing the cavity, blinds, apertures, and glass type, the design process of façade elements that considers interactions was found to be orientation - outer skin - blinds - apertures - cavity - inner skin.

Simplified Prediction Method of Stack-Induced Pressure Distribution in High-rise Residential Buildings

Abstract This paper presents a simple prediction strategy for estimating the pressure distribution in high-rise residential buildings, using key parameters that affect the magnitude and distribution of stack pressure. The strategy is composed of two procedures: first, the stack pressure is predicted from parameters such as the height of the elevator shaft, the location of the neutral pressure level for each shaft, and the interior temperature of each shaft. Then, the pressure distribution of each floor is calculated using the equivalent leakage areas of the exterior and interior walls, by which finally the pressure difference across the exterior walls can be estimated. To verify the feasibility of this strategy, the predicted pressure differences across exterior walls were compared to measured data of a high-rise residential building with multiple elevator zoning. The results show that this strategy can predict pressure distribution quickly with satisfactory results for both the architectural designer and HVAC engineer.