低碳化学与化工2023，Vol.48Issue(6)：127-133,7.DOI:10.12434/j.issn.2097-2547.20230185
不同喷管背压下氨气超声速凝结特性
Supersonic condensation characteristics of ammonia under different nozzle back pressures
摘要
Abstract
Ammonia decomposition to produce hydrogen is an important part of the"ammonia-hydrogen"storage and transportation industry.Due to the limited efficiency of the catalytic decomposition of ammonia,the decomposition gas often contains undecomposed ammonia,so"ammonia-hydrogen"separation is an essential step.Introducing supersonic separation technology to the field of"ammonia-hydrogen"separation,a supersonic condensation model considering the non-equilibrium condensation of ammonia with surge waves was developed,and the condensation flow characteristics of ammonia in Laval nozzles were investigated,and the effects of outlet pressure on the supersonic flow and condensation characteristics of ammonia were explored.The results show that ammonia flows in the Laval nozzles and expands at high velocity,reaching a critical state of condensation after the throat,and nucleates and condenses extensively within a very short distance,and the droplet radius and liquid phase mass fraction continue to increase.After the shock wave occurs,the subcooling rapidly drops to a negative value and the condensed droplets begin to evaporate in large quantities.There is a low temperature zone between between the knots of the surge string.The droplet radius will slightly increase when the subcooling is greater than 0 K,but it will then evaporate rapidly.As the pressure ratio(ratio of outlet back pressure to inlet static pressure)increases from 0.18 to 0.62,the mass fraction of the liquid phase at the Laval nozzle outlet decreases from 0.064 to 0,and the Laval nozzle liquefaction efficiency continues to decrease until it loses its liquefaction capacity completely.关键词
Laval喷管/氨气/凝结/背压/激波Key words
Laval nozzles/ammonia/condensation/back pressure/shock wave分类
能源科技引用本文复制引用
边江,赵子源,陈俊文,郭丹,刘杨,曹学文..不同喷管背压下氨气超声速凝结特性[J].低碳化学与化工,2023,48(6):127-133,7.基金项目
国家自然科学基金(52104071,52074341) （52104071,52074341）
中国博士后科学基金(2022M723497). （2022M723497）
