Design and Performance Study on the Primary & Secondary Helical-Tube Reactor

Using metal hydride (MH) to store hydrogen is developing into an effective approach due to its high H2 storage capacity and prominent safety. As the core of reaction process, the MH reactor and its performance optimization can significantly advance the hydriding and heat transfer rates consequently. In this work, a new primary & secondary helical-tube reactor (P&SHR) is proposed to simplify the structure of the reactor and improve the H2 absorption rate and heat transfer efficiency. The 6 reactors is extensively investigated and related parameters are simulated and optimized by the software COMSOL Multiphysics, revealing that P&SHR owns an outstanding H2 uptake performance under the same working conditions. Further sensitivity analysis indicates that the structural parameters of P&SHR follow the order: Rp > R´p > Pt > P´t > R´s > Rs > R. Based on the results, the optimal structure parameters could be achieved: Rp =18 mm, Rs = 9 mm, R´p = 2.5 mm, R´s = 2.5 mm, Pt = 8 mm, P´t = 9 mm, R = 4 mm. Moreover, the operation parameters including H2 supply pressure, initial temperature and heat transfer coefficient of heat exchange fluid are systematically investigated and analyzed.