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【学术成果】课题组张赞坚在西安交通大学学报发表文章《低流阻火箭煤油的超临界压力流动与换热特性》
发布者: 刘朝晖 | 2018-09-04 | 3836

为探索超临界压力下减阻剂对高温火箭煤油的减阻效果,本文在压力15 MPa,质量流速17000-50000 kg/m2s (对应常温流速约20-60 m/s),流体温度常温-360 ℃,和热流密度2.5-30 MW/m2的试验条件下,对火箭煤油M和添加减阻剂的低流阻火箭煤油M-3在模拟主动冷却通道φ2×0.5 mm高温合金钢管内的流动特性与换热特性进行研究。研究发现:(1)在本文研究条件下,煤油传热机理为超临界压力单相类液态强制对流换热;(2)减阻剂对火箭煤油的减阻效果明显,减阻率最高可达60%;随着流体温度增加,雷诺数增加,减阻剂的减阻效果降低,减阻率最低下降至约20%;(3)添加减阻剂后,煤油传热性能显著弱化,但高雷诺数下,减阻煤油的换热性能基本维持不变,减阻煤油与火箭煤油的努塞尔数之比约为0.5;(4)雷诺数小于约63000,减阻效果大于传热弱化效果;雷诺数大于约63000,结论相反。

 

In order to explore the drag reduction effect of the drag reducer on rocket kerosene under supercritical pressure and high temperature conditions, flow characteristics and heat transfer characteristics of rocket kerosene M and low-flow resistance rocket kerosene M-3 with drag reducer were investigated in a φ2×0.5 mm high-temperature alloy steel tube as active cooling channels. Experiments were conducted at a pressure of 15 MPa, mass flow rates of 17000-50000 kg/m2s (corresponding to the normal temperature flow rates of about 20-60 m/s), and heat flux range of 2.5 ~30 MW/m2. It indicated that: (1) The heat transfer mechanism of the rocket kerosene under the test conditions was supercritical liquid-like forced convection heat transfer. (2) The drag reducing effect of drag reducer on rocket kerosene was obvious, and the max. drag reducing rate achieved about 60%; with the increasing fluid temperature, the Reynolds number increased and the dray reduction effect of the drag reducer decreased, and the the min. drag reducing rate achieved about 20%. (3) For the rocket kerosene with the drag reducing agents, the heat transfer reduction occurred significantly. However, the heat transfer performance of the kerosene M-3 hardly changed at high Reynolds number conditions, and the Nu of M-3 to M kept at about 0.5. (4) While the Reynolds number was below 63000, the drag reduction effect was greater than the heat transfer reduction. While the Reynolds number was greater than 63000, the results reversed.