Fluid Dynamics最新文献_第4页

Experimental Investigations on the Vectoring Characteristics of the Axisymmetric Divergent Bypass Dual Throat Nozzle 轴对称发散旁通双喉喷嘴矢量特性的实验研究

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-10-01 DOI: 10.1134/S001546282460295X

Y. S. Wang, J. L. Xu, S. Huang

{"title":"Experimental Investigations on the Vectoring Characteristics of the Axisymmetric Divergent Bypass Dual Throat Nozzle","authors":"Y. S. Wang, J. L. Xu, S. Huang","doi":"10.1134/S001546282460295X","DOIUrl":"10.1134/S001546282460295X","url":null,"abstract":"The greater thrust-vector angles can be obtained in the axisymmetric divergent bypass dual throat nozzle (ADBDTN). Meanwhile, the axisymmetric divergent bypass dual throat nozzle also has a certain flow adaptive capability and can solve the starting problems existing in the non-vectored state. In the present paper, the results of experimental investigations on the vectoring characteristics of the axisymmetric divergent bypass dual throat nozzle are given. By comparing the structures of the flow field obtained from experiments and numerical simulations as well as the wall static pressure distributions along the flow direction and circumferential direction, it can be seen that, as the nozzle pressure ratio (NPR) increases, flow reaches a critical state near the nozzle exit, and incompletely expanded flow in the cavity continues to accelerate after flowing out of the nozzle, a diamond-shaped structure with alternating shock and expansion wave systems appears downstream of the nozzle exit, and the flow field structures in the cavity are no longer changed when NPR ≥ 6. In addition, the static pressure distributions on the upper and lower wall surfaces of the cavity of the nozzle obtained from the experiments are in good agreement with the results of the numerical simulations, and the wall static pressures in the cavity are basically symmetrically distributed at various circumferential angles.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 4","pages":"832 - 842"},"PeriodicalIF":1.0,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142595381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Numerical Study on the Effect of the Nozzle Pressure Ratio on the Starting Characteristics of the Axisymmetric Divergent Dual Throat Nozzle 喷嘴压力比对轴对称发散双喉喷嘴启动特性影响的数值研究

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462823603297

Y. S. Wang, J. L. Xu, S. Huang

{"title":"Numerical Study on the Effect of the Nozzle Pressure Ratio on the Starting Characteristics of the Axisymmetric Divergent Dual Throat Nozzle","authors":"Y. S. Wang, J. L. Xu, S. Huang","doi":"10.1134/S0015462823603297","DOIUrl":"10.1134/S0015462823603297","url":null,"abstract":"The effect of nozzle pressure ratio (NPR) on the starting characteristics of an axisymmetric divergent dual throat nozzle is investigated numerically. The steady and unsteady numerical simulation methods are used to study the internal flow field of the nozzle and variation in the related performance parameters as a function of the nozzle pressure ratio. The results show that for change in the total pressure of the nozzle inlet flow or back pressure under the same nozzle pressure ratio, the flow field structures in the nozzle cavity remains basically the same, and there is a little difference between the unsteady numerical simulation results and the corresponding time-independent numerical simulation results. In addition, the discharge coefficient of the nozzle increases rapidly with the increase of the nozzle pressure ratio, and then changes only slightly when the nozzle pressure ratio reaches a certain value. With increase in the nozzle pressure ratio, the thrust coefficient of the nozzle will oscillate in the initial stage, then gradually decrease, and then slowly increase, and suddenly decrease near the critical nozzle pressure ratio (NPRcr), and then gradually increase. The typical flow field structures in the cavity under the starting and non-starting conditions are presented before and after reaching the critical nozzle pressure ratio at which the thrust coefficient of the nozzle suddenly drops.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 3","pages":"612 - 621"},"PeriodicalIF":1.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572186","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of a Snow Cover on Hydrodynamic Loads of a Slender Body Moving in Fluid beneath an Ice Cover 冰雪覆盖对在冰盖下流体中运动的纤细物体的水动力载荷的影响

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824602274

V. L. Zemlyak, V. M. Kozin, A. V. Pogorelova

引用次数: 0

Aerodynamic Analysis of Hypersonic Gliding Vehicles with Wide-Speed Range Based on the Cuspidal Waverider 基于 Cuspidal Waverider 的宽速度范围高超音速滑翔飞行器气动分析

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462823603285

Z. Xie, Z. T. Zhao, W. Huang, C. Y. Liu, G. Choubey

{"title":"Aerodynamic Analysis of Hypersonic Gliding Vehicles with Wide-Speed Range Based on the Cuspidal Waverider","authors":"Z. Xie, Z. T. Zhao, W. Huang, C. Y. Liu, G. Choubey","doi":"10.1134/S0015462823603285","DOIUrl":"10.1134/S0015462823603285","url":null,"abstract":"In order to study the variation in the lift performance as a function of the angle of attack of a hypersonic gliding vehicle under supersonic (hypersonic) conditions, the cuspidal waverider was taken as the object of this study, and the variation in the lift performance depending on the angle of attack was simulated for its design condition (M = 3.86 and H = 25 km) and hypersonic incoming flow condition (M = 8 and H = 25 km). It was also compared with the delta-wing Model 1 with the same leading-edge swept angle and Model 2 with the same spread length, respectively. The obtained results show that the zero-lift angle of attack and the critical angle of attack of the cuspidal waverider are both greater than those of the Model 1 and Model 2. The critical angle of attack increases with the free-stream Mach number for all three models. The maximum lift coefficient angle of attack on the upper surface of the cuspidal waverider decreases with increase in the Mach number, contrary to Models 1 and 2, and this relates to the degree of expansion of the free-stream flow conditions, the model layout, and the vortex structure formed on the leeward side.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 3","pages":"622 - 637"},"PeriodicalIF":1.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Dynamic Characteristics of the Droplet Impact on the Ultracold Surface under the Engine Cold Start Conditions 发动机冷启动条件下液滴撞击超冷表面的动态特性

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824600068

S. Jin, W. Zhang, Z. Guo, Y. Yuan, Z. Shi, Y. Liu, J. Yan

{"title":"Dynamic Characteristics of the Droplet Impact on the Ultracold Surface under the Engine Cold Start Conditions","authors":"S. Jin, W. Zhang, Z. Guo, Y. Yuan, Z. Shi, Y. Liu, J. Yan","doi":"10.1134/S0015462824600068","DOIUrl":"10.1134/S0015462824600068","url":null,"abstract":"The impact of liquid droplets on the ultracold surface affects significantly the cold start performance of internal combustion engines but the splash and spreading characteristics after impacting on the ultracold surface are not clearly understood. Therefore, droplets with various physical parameters impacting on the Al–Si alloy surface have been selected for the study under various surface temperatures (–40°C ≤ (~{{T}_{s}}~) ≤ 25°C) and droplet impact velocities (0.96 m/s ≤ (~{{V}_{0}}~) ≤ 3.52 m/s). The ultracold surface (({{T}_{s}}) = –40°C) is beneficial for corona splash, and droplets with the higher Oh number impacting on the ultracold surface easily produce corona splash as the main splash pattern. The ultracold surface assisted in enhancing the stability of the levitated lamella formation, and avoided the effects of rough surfaces, so the upper splash criterion is established to predict the transition from spreading to splash. The decreasing surface temperature reduces the maximum spreading diameter (({{{{beta }}}_{{{text{max}},{text{lt}}}}})) of low solidification point droplets (ethanol, n-propanol, and winter diesel). Based on the assumptions of qualitative temperature, the empirical correlation of the ({{{{beta }}}_{{{text{max}},{text{lt}}}}}) is created for the Ts from 25 to –40°C.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 3","pages":"594 - 611"},"PeriodicalIF":1.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Flexural-Gravity Waves in an Ice Cover Exited by Periodically Varying Moving Perturbations 周期性变化的移动扰动所产生的冰盖中的挠曲重力波

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824602213

Zh. V. Malenko, A. A. Yaroshenko

引用次数: 0

Mathematical Model of Water- and Oil-Soluble Tracers Transfer in Studying Multistage Hydraulic Fracturing 研究多级水力压裂过程中水溶性和油溶性示踪剂转移的数学模型

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824600287

A. B. Mazo, M. R. Khamidullin, K. A. Potashev, A. A. Uraimov

引用次数: 0

Wave Diffraction on an Ice Sheet in the Presence of Shear Current 剪切流作用下冰原上的波衍射

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824602821

L. A. Tkacheva

引用次数: 0

Dynamics of Ion and Electron Flows in the Penning Discharge Chamber 潘宁放电室内的离子和电子流动力学

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824602286

S. T. Surzhikov

引用次数: 0

Simulation of the Development of Richtmyer–Meshkov Instability and Transition to Developed Turbulence 模拟里氏-梅什科夫不稳定性的发展和向发达湍流的过渡

IF 1 4区工程技术

Fluid Dynamics Pub Date : 2024-07-05 DOI: 10.1134/S0015462824600317

V. V. Zmushko, M. I. Polishchuk, A. N. Razin, A. A. Sinel’nikova, A. N. Shcherbakov

{"title":"Simulation of the Development of Richtmyer–Meshkov Instability and Transition to Developed Turbulence","authors":"V. V. Zmushko, M. I. Polishchuk, A. N. Razin, A. A. Sinel’nikova, A. N. Shcherbakov","doi":"10.1134/S0015462824600317","DOIUrl":"10.1134/S0015462824600317","url":null,"abstract":"A criterion for estimating the instant of transition from the stage of development of the Richtmyer–Meshkov instability to developed turbulence on rough contact interfaces of layered gas systems is proposed. A number of laboratory experiments are simulated. In the first series of experiments, the Richtmyer–Meshkov instability arises on two contact interfaces of a thin gas layer after passage of a shock wave. In the experiments, a thin layer (corrugated gas curtain) is formed by pumping a heavy gas (SF6) through a nozzle block across an air-filled shock tube. In the second series of experiments, the shock wave passes across the contact interface of two gases of different densities (air-SF6 and He-SF6 layerings) perturbed along a sinusoid. In this series of experiments, the end face of the tube is either connected to the atmosphere or closed by a rigid wall. Development of the Richtmyer–Meshkov instability and transition to turbulent mixing are simulated using the implicit large eddy (ILES) method by means of the MIMOZA technique. A comparison with the available experimental information is made.","PeriodicalId":560,"journal":{"name":"Fluid Dynamics","volume":"59 3","pages":"444 - 464"},"PeriodicalIF":1.0,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572240","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0