수소 전기차용 액체 수소 저장시스템 압력해소밸브 내 스템의이동거리에 따른 극저온 환경에서 열유동 특성 변화

Abstract

Currently, due to global warming, there is a significant expansion of carbon neutrality policies across the world,focusing on eco-friendly vehicles like hydrogen and electric models. This study examines the fluid flow, direction ofgravity, and distance between the stem and body seats, using CFD to determine the exact specifications of thespring required for the pressure relief valve of the hydrogen tank utilised in a liquid hydrogen electric vehicle. Under the given boundary conditions, fluid flow was set to both laminar and turbulent, and the direction of gravitywas adjusted to align with and oppose the flow direction at the valve, followed by a comparative and analyticalstudy. The findings revealed that there were no noticeable changes in the pressure difference between the inlet andoutlet, and the temperature difference between the outlet and the inlet did not exhibit any clear trends. Thevariations in the density and volume flow rate at the inlet and outlet varied correspondingly with the temperaturemechanism, displaying a matching trend for each factor. Results showed that the mass flow was greatest at adistance of 5 mm between the body and stem seats, with turbulent flow and direction of gravity in the negative-ydirection.