Abstract:  For fishery vessels, once the ammonia in the cabin leaks and spreads, it will cause serious environmental pollution and casualties. Therefore, the ammonia leakage detection device is installed for detecting. Since it is not easy to move the installed detection device, the installation position needs to be considered properly in advance. Based on the Fluent software, the numerical simulation of ammonia leakage in the freezing cabin of the fishery vessel is carried out to study the concentration changes of ammonia in the cabin in different leakage directions and positions. The results show that the change of the leakage direction has little effect on the ammonia detection at the monitoring points near the top of the cabin and the bulkhead. The change of the leakage position has a great effect on the ammonia detection at the monitoring points. The ammonia detection at the monitoring point in the higher position is more accurate. After the ammonia leaks and spreads, the concentration is high near the bulkhead and the top of the cabin. Therefore, the ammonia leakage detection device is preferably to be installed in the upper position of the freezing cabin, and detection devices is required to be arranged near the top of the cabin and the bulkhead to determine whether the ammonia leaks.

Key words: fishery vessel, ammonia leakage, numerical simulation, installation position

摘要： 渔业船舶舱室内一旦氨气发生泄漏扩散，就会引起严重的环境污染和人员伤亡，为此设置了用以检测氨气泄漏探测装置。由于安装好的探测装置不易挪动位置，因此需要事先对安装位置考虑妥当。本文基于Fluent软件对渔业船舶冷冻舱室氨气泄漏过程进行数值模拟，研究氨气在不同泄漏方向和不同泄漏位置下的舱内质量浓度变化。研究表明，泄漏方向的变化对舱顶与舱壁附近监测点的氨气检测影响不大，泄漏位置的改变对监测点的氨气检测影响较大，较高位置处的监测点对氨气检测更为精确，氨气泄漏扩散后在舱壁附近和舱室顶部浓度较高。因此，氨气泄漏探测装置最好安装在冷冻舱室偏上位置，舱壁与舱顶附近都需要布置探测装置，有利于确定氨气是否泄漏。

关键词: 渔业船舶, 氨气泄漏, 数值模拟, 安装位置