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为研究幂律型凝胶推进剂在管路中的流动特性,对直径4~14 mm,长度0.5~2.0 m的一组直圆管和直径6 mm,弯角20°~90,°弯曲半径比1~5的一组弯管,在1~30 m/s的流速下,用3种模拟液进行了实验和仿真。对收缩角10°~50°,收缩比3~1.5的收缩和扩张管,在流速1~30m/s的范围内,用模拟液进行了仿真。结果表明,其它条件相同时,管长、弯角、流速和收缩比增加,流动损失增加;凝胶推进剂在管路中呈“柱塞”形流动,其特性取决于流速、流变指数和稠度系数;管壁附近的剪切速率最大,表观粘度最小;弯管内侧剪切速率小于外侧剪切速率;收缩型截面中,剪切速率逐步增大,粘度逐步降低;突缩和突扩截面存在低速回流区。
In order to study the flow characteristics of power-law gel propellant in pipeline, a series of straight tubes with a diameter of 4 ~ 14 mm and length of 0.5 ~ 2.0 m and a diameter of 6 mm, a bending angle of 20 ° ~ 90, a bending radius Compared with a set of elbow from 1 to 5, experiments and simulations were carried out with three kinds of simulated fluids at a flow rate of 1 to 30 m / s. For the contraction and expansion tubes with the contraction angle of 10 ° ~ 50 ° and the shrinkage ratio of 3 ~ 1.5, the simulation was carried out with the simulation liquid at a flow rate of 1 ~ 30m / s. The results show that the tube length, bend angle, flow rate and shrinkage ratio increase and the flow loss increases when the other conditions are the same. The characteristics of the gel propellant in the pipeline is “plunger” Index and Consistency Coefficient; the shear rate near the pipe wall is the highest and the apparent viscosity is the smallest; the shear rate inside the elbow is less than the outside shear rate; in the shrinkage cross section, the shear rate gradually increases and the viscosity decreases gradually; Sudden expansion section There is a low velocity recirculation zone.