本文關鍵詞：開放空腔殼體入水過程多相流動特性研究　出處：《哈爾濱工業(yè)大學》2017年博士論文　論文類型：學位論文

  更多相關文章： 開放空腔殼體 多相流 入水空泡 空腔擾動 運動穩(wěn)定性 勢流理論

【摘要】：開放空腔殼體是一種含有中空腔體的殼體結構,在以開放端首先撞擊自由液面的入水過程中,空腔內氣體壓縮、液體流入,形成一個氣、液兩相耦合流動空間,并通過開放端與外部流場連通,形成內、外流場間耦合變化,涉及到固、液、氣三相運動和內、外兩個流場的多流域耦合運動問題。在這種復雜流動環(huán)境下,開放空腔殼體入水流動現(xiàn)象與傳統(tǒng)實心運動體入水流動現(xiàn)象截然不同,入水空泡流動特性、流場結構特性、流體動力特性和水下彈道特性均將發(fā)生質的改變,因此開展開放空腔殼體入水多相流動特性研究具有重要的理論意義和實用價值。本文采用勢流理論、數值模擬和實驗相結合的方法,針對開放空腔殼體入水過程中入水空泡流動演化、非定常流場分布、流體動力及入水運動穩(wěn)定性等問題開展了研究,主要研究內容和成果如下:基于勢流理論分析方法,建立了適用于開放空腔殼體入水運動的理論模型。根據開放空腔殼體入水氣、液、固耦合運動特征和無旋流動假設,分別建立空腔氣體漲縮方程、殼體動力學方程和入水空泡運動學方程;采用勢流理論建立入水運動方程組,求解得到入水運動規(guī)律和入水空泡擴展規(guī)律,并與實驗數據對比驗證了理論模型的適用性。基于高速攝像實驗方法,對開放空腔殼體入水空泡流動方式和演化特性開展研究。開展了不同入水速度條件下的開放空腔殼體入水實驗,獲得了波動和云化兩種流動方式下的入水空泡形態(tài)、尺度等特征,分析了Fr數的入水空泡流動方式的影響,并揭示了兩種流動方式的形成機理和關系;開展了不同開放端開口面積和空腔體積模型的入水實驗,分析了開放空腔結構參數對入水空泡流動方式和演化規(guī)律的影響。基于計算流體力學方法,對開放空腔殼體的入水運動規(guī)律和流體動力特性開展研究。建立了數值計算模型,參照實驗條件開展了相應模擬計算,通過與實驗數據對比驗證了數值方法的有效性;通過對數值計算結果分析,獲得了入水過程殼體軸向阻力演化規(guī)律和側壁面壓力分布特征,分析了開放空腔結構在入水運動過程中對流體動力特性的影響;開展了正浮力開放空腔殼體入水仿真,分析了入水后續(xù)往復上浮-下沉運動規(guī)律和流體動力特性。采用實驗和數值模擬相結合的方法,研究了擾動作用下空腔內/外非定常流場結構特性和空泡階段性局部失穩(wěn)問題。將入水過程分為沖擊階段和后續(xù)的空腔漲縮階段,分別針對兩個階段的特點分析了內/外流場參數分布和壓力波特征;描述了空腔擾動作用下入水空泡的階段性局部失穩(wěn)現(xiàn)象,重點分析了空腔擾動作用方式和擾動引起的空泡局部流動特征及作用機理�；趦A斜入水實驗方法,研究了開放空腔殼體典型入水彈道特性。開展了不同姿態(tài)和入水速度條件下的開放空腔殼體傾斜入水實驗,根據實驗結果描述了傾斜入水空泡演化規(guī)律和典型的入水運動特征,分析了入水空泡和水下彈道的關系,并對入水運動過程進行階段性劃分,分析了運動各階段的運動特征和流體動力特征;通過對比實驗數據分析了初始入水速度和入水姿態(tài)對入水彈道和空泡形態(tài)等運動特征的影響。
[Abstract]:The open cavity is a hollow cavity containing the shell structure, in the open end of the first collision free surface into the water in the process of cavity gas compression, liquid flow, forming a gas liquid two-phase flow, space coupling, and through the open end and the external flow field of connectivity, form, coupling between outflow changes that relates to solid, liquid, gas phase and movement, multi basin coupling problem of two flow field. In this complex flow environment, open cavity flow into the phenomenon and the traditional solid body into the water flow into the water flow characteristics of different phenomena, cavitation, flow field characteristics, hydrodynamic and water under the ballistic characteristics will be a qualitative change, so the open cavity into the water phase flow characteristics research has important theoretical significance and practical value. This paper uses the theory of potential flow, numerical simulation and experiment combination Method for open cavity flow into the water into the water bubble evolution process, the unsteady flow field, hydrodynamic problems and water movement stability were studied, the main research contents and results are as follows: the analysis method based on potential flow theory, a theoretical model is established for open cavity into the water movement. According to the the open cavity into water vapor, liquid, and solid coupling motion characteristics and irrotational flow assumption, equations were established. The gas cavity, shell dynamics equation and kinematics equation of bubble into the water; the potential flow theory of the water dynamic equations are obtained in the water movement and water entry cavity expansion law, and the applicability is verified. The theoretical model is compared with the experimental data. The experimental method based on high speed camera, open to the cavity into the water cavity flow patterns and evolution characteristics are studied. The different speed of water entry. The open cavity into the water samples, obtained the fluctuation and cloud two flow patterns under the water entry cavity, scale and other characteristics, analyzed the influence of Fr number of the water entry cavity flow, and reveals the formation mechanism and the relationship between the two flow modes; carry out the area and the volume of the cavity model the open end of the opening into the water experiment, analyzes the influence of structure parameters on the open cavity into the water bubble flow mode and evolution. Based on computational fluid dynamics methods, research into the water movement and hydrodynamic characteristics of open cavity. A numerical simulation model is established according to the experimental conditions to carry out the corresponding simulation calculation. By comparison with experimental data to verify the validity of the numerical method; through the analysis of numerical calculation results, obtained in water shell axial resistance evolution and side wall pressure distribution characteristics, divided Influence of open cavity structure on fluid dynamic characteristics in the water movement process; carry out positive buoyancy open cavity into the water simulation, analysis of the follow-up water floating - sinking motion reciprocating and hydrodynamic characteristics. Using the method of experiment combined with numerical simulation, the effects of disturbances in the cavity / non fixed constant flow structure characteristic and cavitation stage local instability problem is studied. The entry process is divided into shock stage and subsequent cavity expansion stage, respectively, according to the characteristics of the two stages of internal / external flow field parameters distribution and pressure wave characteristics; describes the stage of cavity disturbance into the water cavity of the partial loss the stability, focus on the analysis of the cavity perturbation function and disturbance of local flow characteristics and the mechanism of cavitation caused by the tilt. The water entry test method based on the research of open cavity of typical water entry trajectory. The open cavity. The different attitude and speed of water entry under the condition of oblique water entry test, according to the experimental results described oblique water entry cavity evolution and typical water movement characteristics, analysis of the relationship between water and underwater ballistic vacuoles, and stages of the water movement process, analysis the motion characteristics and the hydrodynamic characteristics of each stage of the movement; by comparing the experimental data analysis of the initial water velocity and the influence of water on water entry trajectory and attitude motion characteristics. The cavity shape

【學位授予單位】：哈爾濱工業(yè)大學
【學位級別】：博士
【學位授予年份】：2017
【分類號】：O359

【相似文獻】

相關期刊論文 前1條

1 喬海燕,張金龍;高速攝影在魚雷空中飛行段及入水瞬間參數測定中的應用[J];高速攝影與光子學;1987年03期

相關博士學位論文 前2條

1 路中磊;開放空腔殼體入水過程多相流動特性研究[D];哈爾濱工業(yè)大學;2017年

2 何春濤;典型運動體入水過程多相流動特性研究[D];哈爾濱工業(yè)大學;2012年

相關碩士學位論文 前4條

1 宋武超;小型回轉體低速傾斜入水過程流場特性研究[D];哈爾濱工業(yè)大學;2015年

2 梅哲力;細長圓柱體入水的特性研究[D];南京理工大學;2014年

3 郁衛(wèi)東;結構高速入水載荷特性數值研究[D];大連理工大學;2006年

4 張成紅;高速運動體入水和運動體參數的優(yōu)化設計[D];哈爾濱工程大學;2007年

，

本文編號：1412718