• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    Influence of Structure Parameters of Double-angle Liner on Jet Formation

    2012-07-25 06:22:28CHENChuang陳闖WANGXiaoming王曉鳴LIWenbin李文彬LIWeibing李偉兵CHENKui陳奎
    Defence Technology 2012年4期

    CHEN Chuang(陳闖),WANG Xiao-ming(王曉鳴),LI Wen-bin(李文彬),LI Wei-bing(李偉兵),CHEN Kui(陳奎)

    (ZNDY of Ministerial Key Laboratory,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,China)

    Introduction

    The liner structure has an important effect on the performance of jet.Compared with traditional singleangle liner,the double-angle liner can better adjust the jet’s velocity and mass distribution.The jet with higher tip velocity and velocity gradient in the middle and rear can improve the penetration efficiency of the liner[1].The double-angle liner is widely used in missile warhead,such as Hellfire and TOW antitank missiles.Our Red Arrow 9 antitank missile warhead adopts tandem charge structure,and the main charge uses a copper double-angle liner[2].

    The influence of liner structure on the jet formation has been studied extensively.LI,et al[3]studied the effect of liner structure parameter on the formation of multimode penetrator,and optimized a shaped charge structure.GU,et al[4]studied the jet formation of a cylinder-cone liner experimentally and obtained the variation laws of jet tip velocity and length.But,for the double-angle liner,the influence of its structure parameter on the jet formation was not studied at home and abroad.The stand-off distance influences the jet penetration greatly.The increase of stand-off distance will make the jet more fully stretched,and it is beneficial to the penetration.On the other hand,too large stand-off distance will lead to the jet break and affect the penetration seriously.This paper studies the formation of double-angle liner in large stand-off distance numerically.

    By using analysis software LS-DYNA and changing some structure parameters of double-cone liner,such as top cone angle,wall thickness,liner height and height ratio of top cone,their influences on the jet formation are analyzed.

    1 Simulation Model

    1.1 Liner Structure

    The structure of the double-angle liner analyzed in this paper is shown in Fig.1.It consists of a top cone and a bottom cone.The angle of top cone is less than that of bottom.There is a smooth transition between the top and bottom,and the top of liner is designed as the shape of arc-cone combination.The structure parameters of liner include the top cone anglea,wall thicknesst,liner heighthand height ratio of top coneh1.

    1.2 Material Model and Algorithm

    To solve the problem of large deformation,ALE algorithm to calculate the formation process[5]can be used.In the calculation,the high explosive material model and JWL equation of state are used.JWL equation precisely describes the pressure,volume,energy characteristics of detonation gas product of explosive.The expression is

    whereA,B,R1,R2,ωare all constants,Eis the internal energy of explosive per unit volume.

    The liner is made of red copper with density of 8.96 g/cm3.Johnson-Cook material model and Gruneisen equation are used as constitution and state equations respectively.The expression of Gruneisen equation is[6]

    for compression state,and

    for expansion state,whereμ=ρ0/ρ- 1,Cis the velocity of material static body,S1,S2,S3are the parameters relevant to material Hugoniot,γ0is the Gruneisen coefficient,ais the first order volume correction toγ0.The air uses hollow material fluid model,the state equation is linear polynomial.The simulation model is shown in Fig.2.

    Fig.2 Simulation model

    2 Simulation Results and Discussions

    2.1 Influence of Top Cone Angle

    According to the theory of shaped charge,the smaller top cone angle can increase the jet tip velocity and penetration depth.In order to study the jet formation effected by top cone angle only,the charge height is taken as 180 mm,the liner height 140 mm,the wall thickness 2.6 mm,and the height ratio of top cone 50%.The jet formation parameters are calculated when the top cone angle varies from 24°to 32°.Fig.3 shows the parameters at 120 μs after ignition.

    Fig.3 Formation parameters vs.top cone angle at 120 μs

    It can be seen from Fig.3 that,with increase of top cone angle,both the jet tip velocity and tail velocity decrease,but the tail velocity declines slower than the tip velocity,and the jet length decreases gradually.The small top cone angle can increase the tip velocity and the velocity gradient,so that the jet can not extend for a long distance,thus the jet will break earlier.Seeing from the jet formation effect,the jet will break easily when the top cone angle is from 24 °to 26°,so it is not conducive to penetration.Therefore,if the top cone angle is selected as 28°,the jet has a higher tip velocity and ensures that the tip will not break.

    2.2 Influence of Wall Thickness

    In the simulation program,the top cone and bottom cone adopt the same wall thickness.Keeping other liner structure parameters unchanged,the influence of wall thickness on the jet formation can be studied.The charge height is taken as 180 mm,the liner height 140 mm,the top cone angle 28°,and the height ratio of top cone 50%.The wall thickness is selected as 1.8 mm,2.2 mm,2.6 mm,3 mm and 3.4 mm in the simulation.Fig.4 shows the jet formation parameters at 120 μs.

    Fig.4 Formation parameters vs.wall thickness

    It can be seen from Fig.4 that the jet tip velocity,tail velocity and length all decrease with increase of wallthickness.The reason is that the detonation energy is constant in the same charge volume and initiation mode.With the increase of wall thickness,the energy obtained by unit mass of liner decreases gradually,thus the collapsing velocity of liner element declines gradually,and it leads to the decrease of jet tip velocity.But,if the wall is too thin,the tip velocity and the velocity gradient are all also high,so it breaks easily.Therefore the wall thickness can be selected as 2.6 mm.

    2.3 Influence of Liner Height

    Keeping the charge height as 180 mm,the top cone angle 28°,the wall thickness 2.6 mm and the height ratio of top cone 50%,the jet formation is simulated when the liner height varies from 130 mm to 150 mm.The simulation results are shown in Fig.5.

    Fig.5 Formation parameters vs.liner height

    Seeing from the simulation results,with the increase of liner height,the tip velocity and jet length gradually rise;but the jet tail velocity tend to decline.The formation parameters change a little.The reason is that the jet can not stretch fully for the small liner height,and it leads to decrease of jet velocity.On the other hand,for the smaller liner height,the more effective charge acts on the liner element,and its motion velocity increases.In the common effect of two as-pects,the liner height influences the jet formation a little.

    2.4 Influence of Height Ration of Top Cone

    Selecting the height ratio of top cone from 30%to 70%,its influence on the jet formation is studied.The top cone angle,wall thickness and liner height are taken as 28°,2.6 mm and 140 mm,respectively.The simulation results are shown in Fig.6.

    Fig.6 Formation parameters vs.height ratio of top cone

    Figure 6 shows that the tip velocity and length of jet firstly increase and then decrease with the increase of the height ration of top cone.When the ration is 60%,the tip velocity is the maximum.When the ratio varies from 30%to 40%,the gain of tip velocity is larger.The reason is that the height of 40% corresponds to the top particles of jet,so the height ratio should not be too small.The tail velocity of jet presents the same trend to the tip velocity,but its change scope is less than that of tip velocity.Thus,the height ration of top cone can be taken as 60%.

    Based on the above discussions,the final optimized liner structure parameters are the top cone angle of 28°,the wall thickness of 2.6 mm,the liner height of 140 mm and the top cone’s height ratio of 60%,as shown in Tab.1.The jet tip velocity and tail velocity are 9 030 m/s and 2 044 m/s,and its length is 761 mm.The formation effect figure shows that the jet does not break,and the tip velocity is higher.

    Tab.1 Formation effect and parameters of optimized shaped charge

    3 Penetration Experiments

    Taken the stand-off distance as 8 times of the charge diameter,penetration experiments of doubleangle liner to 45#steel target are carried out,and the experiment layout is shown in Fig.7.The sizes of targets areφ160 mm ×500 mm andφ160 mm ×150 mm.The experiment and simulation results of penetration are shown in Fig.8 and Fig.9.Seeing from the picture,target 1-1 and 1-2 are all penetrated,and it shows that the double-angle liner has stronger penetration ability in large stand-off distance.

    Fig.7 Layout of penetration experiment

    Fig.8 Picture of steel specimen

    The experiment and simulation results are shown in Tab.2.It shows that the inlet diameter is bigger,the target 1-1 fractures,and the experiment and simulation results are in good agreement.

    Fig.9 Simulation result of penetration

    Tab.2 Comparison of penetration experiment and simulation results

    4 Conclusions

    The influence of double-angle liner’s structure parameters on the jet formation is studied numerically,and the specific influences of the top cone angle,the wall thickness,the liner height and the height ratio of top cone on the jet formation are obtained.The jet tip velocity gradually decreases with the increase of top cone angle and wall thickness.With the increase of liner height,the tip velocity presents an improving trend.However,the tip velocity presents increasing first and then decreasing with the increase of the height ratio of top cone.The structure parameters are optimized.The simulation results show that the jet has better formation effect in the large stand-off distance.The penetration experiment shows that the penetration depth of double-angle liner can reach to 6.27 times of the charge diameter.This paper provides a reference for further study.

    [1]WANG R C,ZHAO G Z.Terminal effects[M].Beijing:Beijing Institute of Technology Press,1993:257 - 259.(in Chinese)

    [2]ZHOU T S.Summarization of tandem shaped charge warhead[J].Journal of Projectile,Rockets Missiles and Guidance,1997,6(1):61 -65.(in Chinese)

    [3]LI W B,WANG X M,LI W B,et al.Effect of liner configuration parameter on formation of multimode penetrator[J].Journal of Ballistics,2009,21(1):19 -23.(in Chinese)

    [4]GU W B,QU H R,TANG Y.Experimental investigation of jet formation of cylinder—cone shaped charge[J].Chinese Journal of Energetic Materials,2009,17(4):470-474.(in Chinese)

    [5]Livemore.LS-DYNA keyword user's manual[M].California:Livemore Software Technology Corporation,2007.

    [6]LI W B,WANG X M,LI W B.The effect of annular multi-point initiation on the formation and penetration of an explosively formed penetrator[J].International Journal of Impact Engineering,2010,37(4):414 -424.

    手机成人av网站| 亚洲精品久久成人aⅴ小说| 国产一区二区激情短视频 | 夫妻午夜视频| 亚洲欧美精品综合一区二区三区| 一区二区日韩欧美中文字幕| 欧美xxⅹ黑人| 少妇人妻久久综合中文| 91精品伊人久久大香线蕉| 精品少妇一区二区三区视频日本电影| 在线观看免费视频网站a站| 中文字幕另类日韩欧美亚洲嫩草| 在线观看免费午夜福利视频| 制服人妻中文乱码| 国产视频一区二区在线看| 日韩电影二区| 国产女主播在线喷水免费视频网站| 色婷婷av一区二区三区视频| 国产99久久九九免费精品| 啦啦啦啦在线视频资源| 久久亚洲国产成人精品v| 母亲3免费完整高清在线观看| 亚洲伊人久久精品综合| 久久午夜综合久久蜜桃| 亚洲欧美一区二区三区久久| 好男人电影高清在线观看| 欧美+亚洲+日韩+国产| 深夜精品福利| 十八禁人妻一区二区| 一本—道久久a久久精品蜜桃钙片| 热re99久久国产66热| 欧美成人精品欧美一级黄| 欧美老熟妇乱子伦牲交| 日本av免费视频播放| av天堂久久9| 亚洲欧美一区二区三区国产| 欧美黑人精品巨大| 国产女主播在线喷水免费视频网站| 中文字幕色久视频| 午夜福利影视在线免费观看| 男女午夜视频在线观看| 99国产综合亚洲精品| 国产成人一区二区三区免费视频网站 | av片东京热男人的天堂| 精品国产国语对白av| 好男人电影高清在线观看| 女性生殖器流出的白浆| 国产成人一区二区三区免费视频网站 | 亚洲中文日韩欧美视频| 男人舔女人的私密视频| 色网站视频免费| 女警被强在线播放| 丰满少妇做爰视频| 午夜免费成人在线视频| 免费高清在线观看日韩| 国产黄色免费在线视频| 国产精品国产三级专区第一集| 99热国产这里只有精品6| 自拍欧美九色日韩亚洲蝌蚪91| 国产片内射在线| 别揉我奶头~嗯~啊~动态视频 | 久久人妻熟女aⅴ| 亚洲精品日韩在线中文字幕| 亚洲精品一二三| 男人添女人高潮全过程视频| 尾随美女入室| 黄频高清免费视频| 视频在线观看一区二区三区| 男人操女人黄网站| 亚洲av成人精品一二三区| 精品欧美一区二区三区在线| 欧美少妇被猛烈插入视频| 日本午夜av视频| 操美女的视频在线观看| 国产一区亚洲一区在线观看| 久久99热这里只频精品6学生| 亚洲精品国产区一区二| 国产一区二区三区综合在线观看| 香蕉国产在线看| 欧美日韩视频高清一区二区三区二| 性色av一级| 免费在线观看完整版高清| 亚洲人成电影观看| 久久久久久久久免费视频了| 亚洲精品一区蜜桃| 国产成人精品无人区| 大片电影免费在线观看免费| 97人妻天天添夜夜摸| 日韩电影二区| 亚洲天堂av无毛| 中文字幕av电影在线播放| 久久久久久久大尺度免费视频| 久久精品国产亚洲av涩爱| 别揉我奶头~嗯~啊~动态视频 | 欧美+亚洲+日韩+国产| 亚洲成色77777| 女警被强在线播放| 成年人午夜在线观看视频| 精品视频人人做人人爽| 青草久久国产| 91精品伊人久久大香线蕉| 亚洲少妇的诱惑av| 母亲3免费完整高清在线观看| av一本久久久久| 国产视频一区二区在线看| 国产成人一区二区在线| 少妇人妻久久综合中文| 在现免费观看毛片| 国产一卡二卡三卡精品| 国产精品偷伦视频观看了| 午夜免费鲁丝| 丝袜脚勾引网站| videos熟女内射| 日本av手机在线免费观看| 99久久99久久久精品蜜桃| 欧美成人精品欧美一级黄| 国产成人一区二区在线| 母亲3免费完整高清在线观看| 成年人黄色毛片网站| 高清av免费在线| av电影中文网址| 在线观看人妻少妇| 免费看不卡的av| 一级片免费观看大全| 免费不卡黄色视频| 婷婷丁香在线五月| 青青草视频在线视频观看| 久久精品国产综合久久久| 亚洲中文字幕日韩| 欧美亚洲日本最大视频资源| 日本欧美视频一区| 国产日韩欧美在线精品| 少妇被粗大的猛进出69影院| 黄色一级大片看看| 汤姆久久久久久久影院中文字幕| 1024视频免费在线观看| 18禁裸乳无遮挡动漫免费视频| 免费在线观看日本一区| 国产亚洲av片在线观看秒播厂| 国产成人精品无人区| 制服人妻中文乱码| 在线观看人妻少妇| 亚洲美女黄色视频免费看| 啦啦啦视频在线资源免费观看| 亚洲少妇的诱惑av| 一级片免费观看大全| 人人妻人人添人人爽欧美一区卜| 成人国产一区最新在线观看 | 亚洲色图综合在线观看| 精品亚洲成国产av| 国产精品久久久久久人妻精品电影 | 国产精品久久久人人做人人爽| 日韩人妻精品一区2区三区| 午夜免费鲁丝| 国产淫语在线视频| 亚洲色图 男人天堂 中文字幕| 午夜福利视频精品| 欧美在线黄色| 女警被强在线播放| 亚洲精品第二区| 国产一区二区激情短视频 | 在现免费观看毛片| av有码第一页| 国产视频首页在线观看| 国产日韩欧美亚洲二区| 国产黄色免费在线视频| 亚洲精品国产av成人精品| 久久亚洲精品不卡| 国产成人av教育| 欧美国产精品va在线观看不卡| 80岁老熟妇乱子伦牲交| 亚洲国产av影院在线观看| 高清欧美精品videossex| 国产av一区二区精品久久| 后天国语完整版免费观看| 好男人视频免费观看在线| 日韩 欧美 亚洲 中文字幕| 亚洲人成电影观看| 黄色a级毛片大全视频| 人人妻,人人澡人人爽秒播 | 中文字幕精品免费在线观看视频| 亚洲精品美女久久久久99蜜臀 | 80岁老熟妇乱子伦牲交| 亚洲av男天堂| 精品少妇一区二区三区视频日本电影| 精品国产乱码久久久久久男人| 国产精品欧美亚洲77777| 欧美亚洲日本最大视频资源| 亚洲欧美精品自产自拍| 91老司机精品| 精品亚洲成国产av| 欧美日韩一级在线毛片| www日本在线高清视频| 亚洲国产精品999| 亚洲国产av影院在线观看| 9热在线视频观看99| 啦啦啦 在线观看视频| 日韩中文字幕视频在线看片| 国产无遮挡羞羞视频在线观看| 精品国产一区二区三区久久久樱花| 国产亚洲午夜精品一区二区久久| av天堂在线播放| 亚洲精品日韩在线中文字幕| 国产精品熟女久久久久浪| 深夜精品福利| 欧美国产精品一级二级三级| 一级毛片电影观看| www.自偷自拍.com| 制服诱惑二区| 欧美精品亚洲一区二区| 人体艺术视频欧美日本| 两个人看的免费小视频| 日韩电影二区| 桃花免费在线播放| 狠狠精品人妻久久久久久综合| 满18在线观看网站| 国产成人精品久久二区二区免费| 亚洲人成网站在线观看播放| 91麻豆av在线| av天堂在线播放| 亚洲精品久久久久久婷婷小说| 精品久久久精品久久久| 99re6热这里在线精品视频| 日韩中文字幕视频在线看片| 老汉色∧v一级毛片| 免费女性裸体啪啪无遮挡网站| 人人澡人人妻人| 亚洲成人免费av在线播放| 久久99精品国语久久久| 天天躁日日躁夜夜躁夜夜| 欧美黄色片欧美黄色片| 成年女人毛片免费观看观看9 | 国产成人精品无人区| 黄色毛片三级朝国网站| 熟女av电影| 久久久久久亚洲精品国产蜜桃av| 三上悠亚av全集在线观看| 永久免费av网站大全| 啦啦啦在线免费观看视频4| 亚洲国产看品久久| 少妇人妻久久综合中文| 久久久精品区二区三区| 满18在线观看网站| 国产在视频线精品| 亚洲中文av在线| 免费久久久久久久精品成人欧美视频| 久久人人97超碰香蕉20202| 欧美精品人与动牲交sv欧美| 中文字幕高清在线视频| 亚洲国产日韩一区二区| 国产精品免费大片| 国产亚洲av片在线观看秒播厂| 欧美成狂野欧美在线观看| 超碰成人久久| 国产高清不卡午夜福利| 啦啦啦在线免费观看视频4| 欧美变态另类bdsm刘玥| xxx大片免费视频| 国产高清视频在线播放一区 | 国产成人啪精品午夜网站| 亚洲精品国产av蜜桃| 国产黄色免费在线视频| 下体分泌物呈黄色| 免费观看人在逋| 一级毛片女人18水好多 | 脱女人内裤的视频| 久久毛片免费看一区二区三区| 亚洲av男天堂| 亚洲伊人色综图| 久久性视频一级片| 久久国产精品影院| 母亲3免费完整高清在线观看| 亚洲国产最新在线播放| 亚洲成色77777| 国产成人av激情在线播放| 精品国产一区二区三区四区第35| 亚洲精品乱久久久久久| 三上悠亚av全集在线观看| 免费高清在线观看视频在线观看| 手机成人av网站| 国产av精品麻豆| 色视频在线一区二区三区| 国产淫语在线视频| 啦啦啦在线观看免费高清www| 国产爽快片一区二区三区| 婷婷色麻豆天堂久久| 无限看片的www在线观看| 久久鲁丝午夜福利片| 久久久久精品国产欧美久久久 | 国产欧美日韩一区二区三 | 亚洲av电影在线观看一区二区三区| 女人高潮潮喷娇喘18禁视频| bbb黄色大片| 亚洲成人免费电影在线观看 | 另类精品久久| 国产精品 国内视频| 咕卡用的链子| 成人亚洲精品一区在线观看| 国产免费视频播放在线视频| 亚洲精品美女久久av网站| 在线观看国产h片| 男人添女人高潮全过程视频| 婷婷丁香在线五月| 国产真人三级小视频在线观看| 午夜老司机福利片| 天天躁夜夜躁狠狠躁躁| 女警被强在线播放| 亚洲 国产 在线| 国产精品偷伦视频观看了| 一级a爱视频在线免费观看| 免费女性裸体啪啪无遮挡网站| 大片免费播放器 马上看| 亚洲成av片中文字幕在线观看| 亚洲欧洲日产国产| 国产淫语在线视频| 亚洲国产中文字幕在线视频| 午夜福利乱码中文字幕| 欧美国产精品一级二级三级| 国产av一区二区精品久久| 色综合欧美亚洲国产小说| 91成人精品电影| 黄色片一级片一级黄色片| 激情视频va一区二区三区| 视频在线观看一区二区三区| 久久人人爽人人片av| 99国产精品一区二区蜜桃av | 亚洲精品日韩在线中文字幕| 九色亚洲精品在线播放| 日韩一本色道免费dvd| 男人爽女人下面视频在线观看| 免费观看人在逋| 欧美日韩国产mv在线观看视频| av有码第一页| 精品少妇内射三级| 国产免费现黄频在线看| 午夜福利视频精品| 国产男女超爽视频在线观看| 9191精品国产免费久久| 久久中文字幕一级| 丝袜美足系列| 99精国产麻豆久久婷婷| 咕卡用的链子| 男女之事视频高清在线观看 | av有码第一页| 国产av国产精品国产| 黄片小视频在线播放| www.熟女人妻精品国产| 亚洲第一青青草原| 男女高潮啪啪啪动态图| 国产精品国产av在线观看| 2018国产大陆天天弄谢| av欧美777| 熟女少妇亚洲综合色aaa.| 国产精品麻豆人妻色哟哟久久| 国产一区二区在线观看av| 嫩草影视91久久| 黄色片一级片一级黄色片| 18禁观看日本| 18禁黄网站禁片午夜丰满| 亚洲国产欧美日韩在线播放| 亚洲一卡2卡3卡4卡5卡精品中文| 欧美日韩亚洲高清精品| 少妇人妻 视频| www.自偷自拍.com| 最新在线观看一区二区三区 | 欧美人与性动交α欧美精品济南到| 国产精品一二三区在线看| 只有这里有精品99| 久久久久久免费高清国产稀缺| 亚洲人成电影观看| 精品少妇一区二区三区视频日本电影| 91国产中文字幕| 亚洲成人免费电影在线观看 | 欧美日韩福利视频一区二区| 999久久久国产精品视频| 国产欧美日韩综合在线一区二区| 国产在线一区二区三区精| 亚洲av成人精品一二三区| 日韩制服丝袜自拍偷拍| 色婷婷av一区二区三区视频| 国产在线观看jvid| 亚洲欧洲日产国产| 黄片小视频在线播放| 国产精品一区二区免费欧美 | 欧美日韩视频精品一区| 每晚都被弄得嗷嗷叫到高潮| 日韩伦理黄色片| 在线亚洲精品国产二区图片欧美| 国产极品粉嫩免费观看在线| 女人高潮潮喷娇喘18禁视频| 亚洲国产欧美在线一区| 考比视频在线观看| 91老司机精品| 亚洲av日韩精品久久久久久密 | 亚洲国产精品999| 91老司机精品| 久久精品人人爽人人爽视色| 99九九在线精品视频| 国产有黄有色有爽视频| 热99国产精品久久久久久7| 亚洲欧美精品自产自拍| 国产精品免费视频内射| 制服诱惑二区| av线在线观看网站| av又黄又爽大尺度在线免费看| 亚洲国产看品久久| 青春草亚洲视频在线观看| 亚洲男人天堂网一区| 天堂8中文在线网| 亚洲精品美女久久久久99蜜臀 | 国产福利在线免费观看视频| 国产精品99久久99久久久不卡| 天天躁夜夜躁狠狠久久av| 99热全是精品| av福利片在线| 日本91视频免费播放| 各种免费的搞黄视频| 久久狼人影院| 丰满迷人的少妇在线观看| 亚洲成av片中文字幕在线观看| 亚洲 欧美一区二区三区| 国产在线免费精品| 亚洲精品国产av成人精品| 满18在线观看网站| 午夜两性在线视频| 观看av在线不卡| 男人舔女人的私密视频| 少妇的丰满在线观看| 在线观看免费视频网站a站| 中文字幕最新亚洲高清| 岛国毛片在线播放| 精品久久久精品久久久| 男的添女的下面高潮视频| 亚洲精品第二区| 国产精品一国产av| 成人国产一区最新在线观看 | 亚洲视频免费观看视频| 久久99热这里只频精品6学生| 成人亚洲精品一区在线观看| 免费日韩欧美在线观看| 视频在线观看一区二区三区| 晚上一个人看的免费电影| 男女午夜视频在线观看| 久久久久国产一级毛片高清牌| 一区二区日韩欧美中文字幕| 黄色怎么调成土黄色| 午夜福利免费观看在线| 在线 av 中文字幕| 18在线观看网站| 丝袜在线中文字幕| 亚洲伊人久久精品综合| 精品一品国产午夜福利视频| 欧美久久黑人一区二区| 女性生殖器流出的白浆| 欧美精品啪啪一区二区三区 | 18禁黄网站禁片午夜丰满| 在线观看人妻少妇| 免费av中文字幕在线| 91精品三级在线观看| 午夜日韩欧美国产| 最近最新中文字幕大全免费视频 | 视频区图区小说| av在线app专区| 自拍欧美九色日韩亚洲蝌蚪91| 国产欧美日韩一区二区三 | 欧美 亚洲 国产 日韩一| 亚洲国产欧美一区二区综合| 老司机靠b影院| 七月丁香在线播放| 午夜福利乱码中文字幕| 脱女人内裤的视频| 国产伦人伦偷精品视频| 国产精品久久久久久精品电影小说| 十八禁人妻一区二区| 亚洲国产成人一精品久久久| 日本av免费视频播放| 亚洲三区欧美一区| 久久精品久久久久久噜噜老黄| 91成人精品电影| 日本vs欧美在线观看视频| 欧美+亚洲+日韩+国产| 久久久久久亚洲精品国产蜜桃av| 午夜免费男女啪啪视频观看| av在线播放精品| 精品国产一区二区三区久久久樱花| 欧美日韩精品网址| 欧美日韩一级在线毛片| 国产xxxxx性猛交| 久久ye,这里只有精品| 国产一区二区三区综合在线观看| 免费在线观看视频国产中文字幕亚洲 | 性色av乱码一区二区三区2| 午夜激情av网站| 日本午夜av视频| 精品亚洲成国产av| 中国国产av一级| 国产精品一区二区在线观看99| 免费日韩欧美在线观看| 制服诱惑二区| 欧美av亚洲av综合av国产av| 中文字幕最新亚洲高清| 精品久久久久久久毛片微露脸 | 另类精品久久| 日韩大片免费观看网站| 亚洲,欧美精品.| 热re99久久国产66热| av网站免费在线观看视频| 超碰97精品在线观看| 老司机午夜十八禁免费视频| 久久精品aⅴ一区二区三区四区| 久久精品久久精品一区二区三区| 你懂的网址亚洲精品在线观看| 国产日韩欧美视频二区| 国产麻豆69| 久久精品熟女亚洲av麻豆精品| 久久青草综合色| 你懂的网址亚洲精品在线观看| 日韩一区二区三区影片| 操美女的视频在线观看| 宅男免费午夜| 人妻人人澡人人爽人人| 一区二区三区精品91| 女人被躁到高潮嗷嗷叫费观| 成人三级做爰电影| 黄色视频不卡| 丝袜脚勾引网站| 日韩伦理黄色片| 成年动漫av网址| 亚洲精品久久午夜乱码| 男女之事视频高清在线观看 | 久久久亚洲精品成人影院| 18禁观看日本| 欧美国产精品一级二级三级| 视频区欧美日本亚洲| 男人爽女人下面视频在线观看| 美女大奶头黄色视频| 国产精品免费视频内射| 免费人妻精品一区二区三区视频| 婷婷色综合大香蕉| 亚洲一区中文字幕在线| 亚洲欧美精品自产自拍| 国产精品久久久久成人av| 看十八女毛片水多多多| 中文字幕av电影在线播放| 日韩熟女老妇一区二区性免费视频| 啦啦啦在线免费观看视频4| 九草在线视频观看| 真人做人爱边吃奶动态| 男女床上黄色一级片免费看| 国产精品一区二区免费欧美 | 成年动漫av网址| 激情五月婷婷亚洲| 亚洲第一av免费看| www.精华液| 亚洲第一青青草原| av在线播放精品| 国产男女超爽视频在线观看| 一本大道久久a久久精品| 亚洲国产精品一区二区三区在线| 黄色视频在线播放观看不卡| 久久久亚洲精品成人影院| 天堂俺去俺来也www色官网| 国产熟女午夜一区二区三区| av线在线观看网站| 久久久久视频综合| 天天影视国产精品| 国产成人啪精品午夜网站| 午夜福利,免费看| 啦啦啦视频在线资源免费观看| 亚洲九九香蕉| 国产精品一二三区在线看| 成人手机av| 婷婷色综合www| 精品国产一区二区三区四区第35| 国产精品三级大全| 91麻豆精品激情在线观看国产 | 亚洲成av片中文字幕在线观看| 真人做人爱边吃奶动态| 久久99一区二区三区| 韩国高清视频一区二区三区| 中文字幕人妻熟女乱码| 日本五十路高清| 亚洲国产av影院在线观看| 欧美精品高潮呻吟av久久| av网站在线播放免费| 亚洲视频免费观看视频| 久久久久久久精品精品| 成人免费观看视频高清| 一本综合久久免费| 色精品久久人妻99蜜桃| 国产无遮挡羞羞视频在线观看| 国产成人av教育| 国产又爽黄色视频| 免费av中文字幕在线| 国产在线视频一区二区| 一级毛片我不卡| 色精品久久人妻99蜜桃| 少妇粗大呻吟视频| 一级毛片 在线播放| 国产精品香港三级国产av潘金莲 | 亚洲第一青青草原| 亚洲成人手机| 人成视频在线观看免费观看| 亚洲三区欧美一区| 菩萨蛮人人尽说江南好唐韦庄| 在线观看一区二区三区激情| 欧美少妇被猛烈插入视频| 19禁男女啪啪无遮挡网站| 我要看黄色一级片免费的| 伊人亚洲综合成人网| 性色av一级| 亚洲欧洲国产日韩| 国产伦理片在线播放av一区| 亚洲国产精品成人久久小说| 99热网站在线观看|