Hydrogen plays a vital role in the future energy system, especially for spacecraft and fuel cell vehicle. In order to avoid the venting during the liquid hydrogen storage and decrease energy loss in space application, this paper presents a numerical study of the thermal performance of a hydrogen storage tank with nozzle injection and its improvement - a guide tube. Compared with the previous storage tank without guide tube, the chilling performance of the new storage system is enhanced since the guide tube improves the heat transfer and reduces the stagnant region to meliorate the flow circulation. Distribution profiles of temperature and velocity in the storage tank have been attained to evaluate the chilling performance. The key geometric parameters are further optimized by analyzing a series of cases under different geometry settings, from which the optimized ranges of dimensionless parameters have been obtained and studied respectively. This research provides guidelines for geometrical optimization of the liquid hydrogen cryogenic storage tank, and it helps to improve the chilling performance of the storage tank and promote the utilization of hydrogen energy. (C) 2015 Elsevier Ltd. All rights reserved.