액체 수소의 무배기 충진을 위한 극저온 흡착 시스템의 수치적 연구

Abstract

The tank-to-tank refueling process is one of the important issues in liquid hydrogen (LH2) transportation. During refueling, efficient fuel management can be achieved by a no-vent fill (NVF), which is a method to fill the tank without venting. For the successful NVF process, the rapidly generated vapor in the early stage has to be handled not to exceed the limit pressure of a receiver tank. This paper suggests a concept of the compact vapor management system using adsorption for NVF. Physical adsorption at cryogenic temperature has the advantage of treating a large amount of vapor for a short time by adsorbing and storing the vapor at a high density. The numerical model for hydrogen adsorption is established to assess the volumetric hydrogen capacity. This model considers the thermodynamics of the adsorption tank with activated carbon. In calculation processes, the temperature of the adsorption tank is determined by hydrogen adsorption isotherms and the amount of hydrogen inflow. From the simulation results, the adsorption rate and the volume of the cryo-adsorption system are compared to the consumption rate and the volume of the 100 kW-class fuel cells. Furthermore, a parametric study of the cryo-adsorption system is conducted to apprehend the effect of the initial conditions on the volumetric hydrogen capacity.