동절기 STS 물탱크의 단열재 설계에 따른 물의 동결 특성 분석

The purpose of this study is to analyze the freezing characteristics of water in STS water tanks for reservoirs exposed to outside temperatures in winter. A large-scale STS water tank was modeled as a 2D symmetric analysis model, and heat transfer analysis was performed for 48 hours using winter outside temperatures to observe temperature trends in water at the tank’s outer part of the center and supported part of the bottom by insulation thickness. Through the temperature change rate and phase change time of water, the analysis model confirmed that the bottom is more vulnerable to heat loss of water than the side. Furthermore, parametric study was conducted using the insulation placement at the bottom of the tank as a variable and water freezing characteristics were established based on the heat transfer characteristics change according to insulation placement. An effective insulation design was proposed by comparing freezing time for each insulation placement based on minimum and maximum residence time of water.