| 摘要: |
| 为研究初始参数对回转体并联入水空泡及运动特性影响,基于有限体积法,采用realizable k-ε湍流模型、VOF(volume of fluid)多相流模型和Schnerr and Sauer空化模型,并引入重叠网格技术,对不同入水速度、不同初始净距和不同横流速度的回转体并联入水过程进行数值模拟。首先,建立了回转体高速并联入水的数值计算模型,验证了计算方法的有效性。然后,基于此模型开展不同初始参数的并联入水数值计算,得到不同参数下的流场及运动特征。最后,结合计算结果分析了不同参数下并联运动体的空泡形态及特征尺寸变化、侧向与偏航运动规律。研究结果表明,随着入水初速度增大,内侧空化现象越剧烈,同一量纲一的时刻空泡的外侧极径和限制长度增大,回转体量纲一的侧向位移和偏航角越大。随着初始净距减小,同一量纲一的时刻空泡的限制长度越小,回转体的量纲一的侧向位移和偏航角先增大后减小。小横流作用下,迎流与背流回转体的外侧空泡径向尺寸与单体基本相同,而长度略大,随着横流速度增大,并联入水状态的空泡尺寸差异同单体相比增大；内侧空泡的径向尺寸差异较大,其中迎流回转体的内侧空泡极径较大,且随着横流速度增大极径的最大值始终维持在d+D/2左右。横流速度较小时,并联入水回转体头部靠近而尾部远离；横流速度较大时,两回转体头部远离而尾部靠近。 |
| 关键词: 回转体 并联入水 空泡形态 运动特性 数值计算 |
| DOI：10.11918/201909040 |
| 分类号:TV131.2 |
| 文献标识码:A |
| 基金项目:国家自然科学基金(11672094) |
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| Numerical simulation of cavitation and motion characteristics of revolution bodies entering water in parallel |
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YU Delei,WANG Cong,HE Chaojie
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（School of Astronautics, Harbin Institute of Technology, Harbin 150001, China）
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| Abstract: |
| To study the influence of initial parameters on the cavitation and motion characteristics of revolution bodies entering water in parallel, the realizable k-ε turbulence model, the volume of fluid (VOF) multiphase flow model, and the Schnerr and Sauer cavitation model were employed based on the finite volume method. The overlapping grid technique was used to simulate the process of water entry in parallel with different initial speeds, initial clearance distances, and cross-flow speeds. First, a numerical calculation model of high-speed water entry in parallel of revolution bodies was established, and the validity of the calculation method was verified. Then, based on this model, numerical calculations of parallel water entry with different initial parameters were performed to obtain the flow field and motion characteristics under different parameters. Finally, combined with the calculation results, the variations of the cavitation morphology and characteristic size, as well as the lateral and yaw movements of the moving bodies under different parameters were analyzed. Results show that with the increase of the initial velocity of water entry, the inner side cavitation phenomenon was more severe. With the outer polar radius and the limit length of the cavitation at the same dimensionless moment increased, the dimensionless lateral displacement and yaw angle of the revolution body were larger. As the initial clearance distance decreased, the limit length of the cavitation at the same dimensionless moment was smaller, and the dimensionless lateral displacement and yaw angle of the revolution body first increased and then decreased. Under the action of small cross-flow, the radial dimensions of the outer cavitation on the outer side of the revolution body in forward and leeward directions were basically the same with that of the single revolution body, while the length was slightly larger. With the increase of the cross-flow speed, the cavity size differences of parallel moving bodies were greater than that of single body. The radial size differences of the inner cavitation were large, where the polar radius of the inner cavitation of face-flow revolution body was greater, and with the increase of the cross-flow speed, the maximum value of the polar radius maintained around d+D/2. When the cross-flow speed was small, the two revolution bodies tended to be close to the head and far away from the tail; when the cross-flow speed was large, the two revolution bodies tended to be close to the tail and far away from the head. |
| Key words: revolution body water entry in parallel cavity shape motion characteristics numerical simulation |
