Jae-Han Lim

Heating Performance and Occupants′ Comfort Sensation of Low temperature Radiant Floor Heating System in Apartment Buildings of Korea

Abstrct To develop an energy-efficient low-temperature radiant floor heating system in an apartment housing unit from an improved the overall heating system efficiency perspective, it is essential to consider the occupants′ thermal comfort and evaluate the thermal environment and thermal output of the radiant panel. This study evaluated the heating performance of a low temperature radiant floor heating system by monitoring the water flow rates, supply and return water temperatures, indoor room temperatures and floor surface temperatures through field measurements, and surveyed the occupants′ thermal comfort through questionnaires. Based on the results of field measurements and the occupants′ questionnaires, the heating performance and thermal comfort sensation of a low-temperature radiant floor heating system were analyzed. The design considerations of a low temperature radiant floor heating system are suggested.

Characteristic of Thermal Output of Thermally Activated Building System During the Heating Operation According to FDM Analysis

T his study is focused on the evaluation of thermal output of TABS (Thermally Activated Building System). The aim of this study is to evaluate TABS in terms of the temperature difference between heating medium supply temperature () and return temperature (), thermal output and the surface temperature distribution according to the design flow rate and the design flow temperature. Through the transient heat transfer simulation using temperature calculation using Crank-Nicolson FDM using Physibel Voltra 6.0 W, the temperature difference between  and , thermal output and the surface temperature distribution of specific TABS was calculated and evaluated. The results show that specific thermal output and temperature difference at 60°C of supply water temperature were about 162 W/m 2 , 13.6°C respectively

Influence of Drainage Holes on Condensation Risk and Air-tightness of Windows An Experimental Case Study of Triple Glazing PVC Windows

Triple glazing windows incorporate drainage holes on glazing beads or gaskets to provide a path for condensed water from the inside to the outside. These holes are considered to be effective for draining condensed water but may decrease the air-tightness and increase the condensation risk due to the drop in surface temperature resulting from the intake of cold outside air. In this study, the related specifications and documents on the application of drainage holes and previous studies were reviewed. For the triple glazing windows with and without drainage holes, the condensation resistance and air-tightness were evaluated and compared. Condensation resistance and air-tightness were tested in accordance with KS F 2295 and KS F 2292, respectively. The results showed that the use of drainage holes did not have a significant negative impact on the condensation resistance and air-tightness.

Numerical analysis model to evaluate the agricultural solar right in rural area with a consideration of building and infrastructure constructions

Recent construction of building or infrastructure has included many new bridges, in an effort to create new infrastructure while disturbing the natural environment. The new bridges have created disputes over agricultural solar right in rural area. The main issues of the dispute were the reduction of crop yields and increased heating costs. To settle these solar right conflicts, it is necessary to develop an evaluation method and quantitative guidelines for determining the infringement of solar right in rural areas. The objective of this study is to develop a numerical analysis model to evaluate the infringement of agricultural solar right by the construction of infrastructure such as highway bridges. For this purpose, we have reviewed the general mediation process and proposed the numerical analysis model which is based on the WALDRAM diagram method. This model was integrated with the evaluation tool which quantitatively estimates the infringement of agricultural solar access due to the construction of building or infrastructure. And we verified the effectiveness of the proposed numerical model through the application to actual cases.