• <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 ?

    The Coupling VIV Analysis of SCRs with Rigid Swing

    2015-06-01 09:24:20LIUJuanandHUANGWeiping
    Journal of Ocean University of China 2015年4期

    LIU Juan, and HUANG Weiping

    1)Shandong Key Laboratory of Ocean Engineering,Ocean University of China,Qingdao266100,P. R. China

    2)Institute of Civil Engineering,Agriculture University of Qingdao,Qingdao266009,P. R. China

    The Coupling VIV Analysis of SCRs with Rigid Swing

    LIU Juan1),2), and HUANG Weiping1),*

    1)Shandong Key Laboratory of Ocean Engineering,Ocean University of China,Qingdao266100,P. R. China

    2)Institute of Civil Engineering,Agriculture University of Qingdao,Qingdao266009,P. R. China

    With the development of deepwater oil and gas exploration, Steel Catenary Risers (SCRs) become preferred risers for resource production, import and export. Vortex induced vibration (VIV) is the key problem encountered in the design of SCRs. In this study, a new model, the rigid swing model, is proposed based on the consideration of large curvature of SCRs. The sag bend of SCRs is assumed as a rigid swing system around the axis from the hanging point to the touch down point (TDP) in the model. The torque, produced by the lift force and the swing vector, provides the driving torque for the swing system, and the weight of SCRs provides the restoring torque. The simulated response of rigid swing is coupled with bending vibration, and then the coupling VIV model of SCRs is studied in consideration of bending vibration and rigid motion. The calculated results indicate that the rigid swing has a magnitude equal to that of bending vibration, and the rigid motion affects the dynamic response of SCRs and can not be neglected in the VIV analysis.

    rigid swing; vortex induced vibration; steel catenary riser; dynamic model

    1 Introduction

    With the development of offshore oil and gas industry, deepwater resource exploration is expanding greatly, and various innovative floating structures, such as TLPs and Spars, are developed for operating under severe deepwater environment. Risers, connecting wells and floating platforms for production, import and export of resources, are the key component in deepwater development. As a new type of deepwater risers, Steel Catenary Risers (SCRs) with the advantages of low costs and no need of top tension, have become the preferred riser systems in recent years (Huanget al., 2009). Vortex induced vibration (VIV) is a core problem in the design of SCRs, and special configuration and complex flow make the VIV analysis of SCRs much more complicated than Top Tensioned Risers (TTRs) (Cunffet al., 2004; Mekha, 2002; Meng and Chen, 2012; Gaoet al., 2011).

    Many problems of SCRs have been studied and achievements have been made since the first SCR was installed in 1994 (Nakhaee and Zhang, 2010; Hodder and Byrne, 2010; Lie and Kaasen, 2006; Thethi, 2001; Ioannis, 2010; Holtamet al., 2009). Presently, only bending vibration under lift force is considered in VIV studies of SCRs, while the torque, produced by the lift force and the vector, is often neglected, that is, the swing model around an axisis not considered in dynamic model studies of SCRs. A new model, the rigid swing model, is proposed in this paper. The model is based on the consideration of large curvature of sag bends by taking SCRs as a rigid swing system around the axis from the hanging point to the touch down point (TDP). The swing response is then coupled with bending vibration as inertial force and hydrodynamic damping to study the VIV of SCRs. Numerical simulations show that the rigid swing affects the dynamic response of lower parts greatly and can not be ignored in the VIV study of SCRs.

    2 Rigid Swing Model of SCRs

    The rigid swing model of SCRs is shown in Fig.1, where ODC is the SCRs system, O is the hanging point, D is the touch-down point, and C is the connection point for wells and risers. The sag bend of SCRs is assumed as a rigid swing system around the axis from O to D in the model, where A is an arbitrary point on the sag bend, B is the intersection point of the swing plane of point A and the swing axis OD,ωis the unit vector of axis OD,sis the vector from the axis to point A, andFLis the lift force due to an angle betweenFLand the SCRs plane (xoyplane). The torque is produced by the forceFLand the vectors, which provides the driving force for the swing.mgis the weight per unit length of riser and is the restoring force for the swing. OAD is in thexoyplane when the swing system is in balance, point A' is the position of point A after a swing, andrαis the swing angle.

    The swing equation per unit length of risers is derived based on the theory of momentum moment:

    where,mandmaare the mass and the added-mass per unit length of risers,cais the added-damping coefficient,fLzandfLxare the projections of lift force onz- andx-axis, respectively, andrα,, andare the angular displacement, the velocity, and the acceleration of a rigid swing, respectively.sis the vector from the swing axis to a unit of the riser,.sis the norm of the vectors,s1,s2ands3are the projections ofsonx-,y- andz-axis, respectively,

    where (xA,yA,zA) and (xB,yB,zB) are the coordinates of points A and B, respectively, ands3=0 when the system is in balance (Fig.1).

    wheredis the length of axis OD,

    and (xD,yD,zD) and (xO,yO,zO) are the coordinates of points D and O, respectively.

    Fig.1 Rigid swing model of SCRs.

    In the finite element analysis of the rigid motion, an unit of the riser is shown in Fig.2, in whichiandjare the nodes of the unit,x'-axis is the local axis of the unit and the origin is set at nodei.siandsjare the swing vectors of nodesiandj, respectively, and the unit vectorsis expressed by node vectors:

    By substituting the node coordinates and corresponding vectors into Eq. (2), the linear equations about parameteracan be obtained:

    Eq.(3) can be solved as:

    By substituting Eq. (4) into Eq. (2), the unit vector expressed by node vectors is derived as:

    and,

    By bringsands2into Eq. (1), and integrating the equation along the unit and then the riser, the equation of rigid swing of SCRs is derived as:

    whereIis the moment of inertia,Cis the hydrodynamic damping coefficient,Kis the restoring-force coefficient, andMαis the external force moment for rigid swing. Solving Eq. (7) by time-domain method, the swing response of SCRs can be obtained.

    Fig.2 Swing unit of the SCR.

    3 Coupling Analysis of VIV of SCRs

    By considering both bending vibration and rigid swing, VIV of SCRs can be expressed as follows:

    whererb,andare the bending displacement, the velocity and the acceleration of risers, respectively;andare the linear velocity and the acceleration of rigid swing,,, respectively;cis the structure damping andcais the hydrodynamic damping,kis the bending stiffness andfLis the lift force per unit length of risers.

    By moving the terms associated with rigid swing to the right hand side of Eq. (8), the following equation can be obtained:

    Eq. (9) is the popular form of the vibration equation of risers, which shows that the rigid motion is coupled with the bending vibration as inertial force and hydrodynamic damping.

    Eq. (9) can be expressed as coordinate components:

    where (ub,vb,wb),, andare the projections of the bending displacement, the velocity and the acceleration onx-, y-andz-axis, respectively;andare the projections of the linear velocity and the acceleration of rigid swing, where

    whereandare the rigid swing response obtained from Eq. (1).

    Eq. (10) can be solved by the time-domain method and the solutions are the VIV response of SCRs with both bending vibration and rigid swing.

    4 Numerical Simulations

    Based on the nonlinear FEM, a dynamic code of SCRs, Cable3D, was developed (Chen, 2002). The flexible cable theory is applied to simulate risers in the code. By using small extensible slender rods with bending stiffness for SCR modeling, the accurate static configuration and vibration response of SCRs can be obtained with the code (Bai, 2009).

    In this study, the static configuration and the VIV response of a SCR are first simulated using Cable3D, then a dynamic program, named RT_Res, is developed based on the rigid swing model of SCRs. The obtained response is further coupled with bending vibration, a new program, named VRT_Cable, is developed to simulate the VIV of the SCR, and the obtained results are compared with the prediction of Cable3D.

    The SCR is 2500 m long with an outer diameter of 0.355 m and a thickness of 0.025 m. The depth of water is 1100 m and the horizontal distance from the hanging point to the wellhead is 1846 m. The restraint of the hanging point is by hinged joint and the TDP is by elastic restraint. Other main parameters are listed in Table 1. With a top tension of 2100 kN, the static configuration of the SCR is shown in Fig.3; the angle between the tangent direction of the hanging point of the SCR and the vertical is 16°

    Table 1 Key parameters of the SCR and flow

    Fig.3 Static configuration of the SCR.

    The incoming flow is alongx-axis with a speed of 0.20 m s-1and Strouhal constantSt=0.2 (see Table 1 for other flow parameters). The VIV response of the riser is simulated using Cable3D. The history curves of the 18thand 225thnodes are shown in Figs.4-5 and the frequency of the curves is the Strouhal frequency of 0.0769 (see Fig.3 for the location of both nodes).

    Calculated by the program RT_Res in the rigid swing model, the history response of the angular displacement of the riser is shown in Fig.6. It can be seen that the swing angle of the riser is 3×10-4rad. If converted to a linear displacement using the equationrr=ar×s, the linear displacement of the 225thnode is 0.03 m and is equal to that of the bending vibration as shown in Fig.5. The rigid swing of the riser is a forced motion, and therefore the frequency of the swing is the Strouhal frequency 0.0769, which is the same as that of the bending vibration.

    Fig.4 The VIV response history of the 18thnode.

    Fig.5 The VIV response history of the 225thnode.

    Fig.6 The history response of rigid swing of the SCR.

    Figs.7-8 are the VIV history curves of the 18thand 225thnodes with rigid swing simulated by VRT_Cable. It can be seen that the swing response has a small effect on the 18thnode but a great effect on the 225thnode. Because the swing vector at the lower part of the riser is larger than that at the upper part, the linear displacement at the lower part is greater for the case of the same swing angle, and, therefore, the swing responses affect the lower part of risers more significantly and should be considered as an important factor in the VIV analysis of SCRs.

    Fig.7 The response history of the 18thnode with rigid swing.

    Fig.8 The response history of the 225thnode with rigid swing.

    Huanget al.(2011, 2012) studied the VIV of flexible cylinders based on model experiments, their results indicated that when VIV is beyond the lock-in district, the vortex frequency of the model is not equal to Strouhal frequency and it changes with different natural frequencies of the model; besides, the VIV of a cross flow is a strong random vibration and the response frequency is in a wide range, that is, the vortex shedding mode of the wake is very unstable due to the vibration of cylinders. Based on the results, Liu and Huang (2013) developed a lift force model by considering structure vibration and its coupling with fluid, and this revised model describes the stochastic force with varying frequencies and amplitudes.

    Based on the revised lift force model the program CPVRT_Cable is updated to simulate the VIV of a SCR, and the response of the riser is a stochastic vibration with varying frequencies and amplitudes. Figs.9 and 10 are the responses of the 84thand 276thnodes of the riser; the dashed line and the solid line are history curves with and without rigid swing, respectively. The location of both nodes is shown in Fig.3, and Figs.9 and 10 also show that the rigid swing affects the upper part of the riser slightly but has a great effect on the lower part.

    Fig.9 The VIV history of the 84thnode with rigid swing.

    Fig.10 The VIV history of the 276thnode with rigid swing.

    Fig.11 Response spectrum of the 276thnode without rigid swing.

    Fig.12 Response spectrum of the 276thnode with rigid swing.

    Fig.11 is the VIV response spectrum of the 276thnode without the rigid swing, and the peak frequency of the curve is slightly lower than the Strouhal frequency of 0.0769. Fig.12 is the spectrum of the node with the rigid swing. Comparing the two figures, it can be seen that the curve of Fig.12 contains more frequency components, and the peak and bandwidth are rather large. The comparison also indicates that the response of the riser and the corresponding added damping of the fluid have increased significantly with the rigid swing of the SCR.

    5 Conclusions

    SCRs, connecting floating platforms and wellheads as both flow lines and risers, have become the popular riser system in marine resource exploration. Many studies have been conducted in the past several decades, such as dynamic characteristics of SCRs, SCR coupled with platforms and VIV models of SCRs.

    In this study, the dynamic modeling results of the vortex induced vibration of SCRs are examined. By introducing the concept of rigid swing, a new dynamic model in the VIV study of SCRs is developed. The model can be used to simulate the dynamic characteristics of SCRs and to reproduce the out-of-plane motion of SCRs reasonably well. Simulation results show that the swing responses have the same order of magnitude as the bending vibration, and affect the lower part of risers more significantly and should not be ignored in the VIV analysis of SCRs.

    The assumption that the touch down point is a fixed point may introduce errors to model results, and further research is necessary on the rigid swing model of SCRs.

    Acknowledgements

    The study is funded by the National Natural Science Foundation of China (51079136, 51179179, 51239008), and our thanks also go to Professor Jun Zhang of Texas A&M University, the copyright owner of Cable3D.

    Bai, X. L., 2009. Study on method for nonlinear analysis of deepwater SCR based on inertial coupling. PhD thesis. Ocean University of China, 38-48 (in Chinese with English abstract).

    Chen, X. H., 2002. Studies on dynamic interaction between deep-water floating structures and their mooring/tendon system. PhD thesis. Civil Engineering Department, Texas A&M University, 15-28.

    Cunff, C. L., Averbuch, D., and Biolley, F., 2004. Influence of current direction on VIV of a steel catenary riser.Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering. Vancouver, Canada, ASME, 1: 23-30.

    Gao, Y., Zong, Z., and Sun, L., 2011. Numerical prediction of fatigue damage in steel catenary riser due to vortex-induced vibration.Journal of Hydrodynamics (Ser. B), 23 (2): 154-163.

    Hodder, M. S., and Byrne, B. W., 2010. 3D experiments investigating the interaction of a model SCR with the seabed.Applied Ocean Research, 32: 146-157.

    Holtam, C. M., Baxter, D. P., Thomson, R. C., and Ashcroft, I. A., 2009. Influence of fatigue loading on the engineering critical assessment of steel catenary risers in sour deepwater oil and gas developments.Key Engineering Materials, 834 (413): 313-325.

    Huang, W. P., Bai, X. L., and Li, H. J., 2009. State of the art ofresearch and development of overseas deepwater steel catenary risers.Periodical of Ocean University of China, 39 (2):290-294 (in Chinese with English abstract).

    Huang, W. P., Cao, J., Zhang, E. Y., and Tang, S. Z., 2011. Study on vortex induced vibration in two-degree-of-freedoms of flexible cylinders.Chinese Journal of Theoretical and Applied Mechanics, 43 (2): 436-440 (in Chinese with English abstract).

    Huang, W. P., Liu, J., and Wang, A. Q., 2012. A spectrum of the lift force on a cylinder with fluid-structure interaction based on experiment.Engineering Mechanics, 29 (2): 192-196, 204 (in Chinese with English abstract).

    Ioannis, K. C., 2010. On the effect of internal flow on vibrating catenary risers in three dimensions.Engineering Structures, 32 (10): 3313-3329.

    Lie, H., and Kaasen, K. E., 2006. Modal analysis of measurements from a large-scale VIV model test of a riser in linearly sheared flow.Journal of Fluids and Structures, 22: 557-575.

    Liu, J., and Huang, W. P., 2013. A nonlinear vortex induced vibration model of marine risers.Journal of Ocean University of China, 12 (1): 32-36.

    Mekha, B. B., 2002. On the wave and VIV fatigue of steel catenary risers connected to floating structures.Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering. Oslo, Norway, ASME, 1: 57-63.

    Meng, D., and Chen, L., 2012. Nonlinear free vibrations and vortex-induced vibrations of fluid-conveying steel catenary riser.Applied Ocean Research, 34: 52-67.

    Nakhaee, A., and Zhang, J., 2010. Trenching effects on dynamic behavior of a steel catenary riser.Ocean Engineering, 37 (2):277-288.

    Thethi, R., 2001. Soil interaction effect on simply catenary riser response.Pipe & Pipeline International, 46 (3): 15-24.

    (Edited by Xie Jun)

    (Received April 7, 2013; revised May 9, 2013; accepted January 6, 2015)

    ? Ocean University of China, Science Press and Springer-Verlag Berlin Heidelberg 2015

    * Corresponding author. Tel: 0086-532-66781850 E-mail: wphuang@ouc.edu.cn

    日本免费一区二区三区高清不卡| 欧美成狂野欧美在线观看| 国产精品久久久人人做人人爽| 香蕉丝袜av| 精品欧美国产一区二区三| 日本三级黄在线观看| 亚洲国产日韩欧美精品在线观看 | 亚洲午夜理论影院| 国内少妇人妻偷人精品xxx网站 | 别揉我奶头~嗯~啊~动态视频| 国内久久婷婷六月综合欲色啪| 亚洲av成人一区二区三| av天堂在线播放| 国产精品免费一区二区三区在线| 18美女黄网站色大片免费观看| 久久草成人影院| 国产99久久九九免费精品| 亚洲人成网站在线播放欧美日韩| 两个人免费观看高清视频| 中文字幕熟女人妻在线| 99精品久久久久人妻精品| 天堂影院成人在线观看| 日本黄色视频三级网站网址| 欧美黄色片欧美黄色片| 后天国语完整版免费观看| 久久久久精品国产欧美久久久| www日本在线高清视频| www.自偷自拍.com| 巨乳人妻的诱惑在线观看| 亚洲av成人不卡在线观看播放网| 亚洲黑人精品在线| 国产欧美日韩一区二区精品| 国产成人aa在线观看| 91麻豆av在线| 国产1区2区3区精品| 日韩欧美在线乱码| 日本熟妇午夜| 波多野结衣高清无吗| 巨乳人妻的诱惑在线观看| 黄色女人牲交| 国产不卡一卡二| 午夜两性在线视频| 三级男女做爰猛烈吃奶摸视频| 国产精品亚洲美女久久久| 天堂av国产一区二区熟女人妻 | 天天一区二区日本电影三级| 亚洲av成人一区二区三| 中文在线观看免费www的网站 | 老汉色av国产亚洲站长工具| 国产精品日韩av在线免费观看| 一本一本综合久久| 精品国产乱子伦一区二区三区| 一本综合久久免费| 日本成人三级电影网站| 最近最新中文字幕大全电影3| 午夜福利成人在线免费观看| 青草久久国产| 一本久久中文字幕| 久久九九热精品免费| 久久性视频一级片| 亚洲欧美激情综合另类| 国产69精品久久久久777片 | 中文资源天堂在线| 国产成人精品久久二区二区免费| √禁漫天堂资源中文www| 日本一本二区三区精品| 精品高清国产在线一区| 又黄又粗又硬又大视频| 搞女人的毛片| 99久久久亚洲精品蜜臀av| 亚洲中文字幕日韩| 91字幕亚洲| 亚洲,欧美精品.| 欧美成人性av电影在线观看| 青草久久国产| 熟女少妇亚洲综合色aaa.| 亚洲精品av麻豆狂野| 亚洲欧美精品综合一区二区三区| 亚洲自拍偷在线| 麻豆国产97在线/欧美 | 91麻豆av在线| 精品久久久久久久人妻蜜臀av| 国产精品久久久久久久电影 | 国产精品电影一区二区三区| 亚洲午夜理论影院| 国产高清视频在线播放一区| 无遮挡黄片免费观看| 国产精品一及| 国产精品日韩av在线免费观看| 久久久精品欧美日韩精品| 中国美女看黄片| 性欧美人与动物交配| 国产精品一区二区免费欧美| 亚洲va日本ⅴa欧美va伊人久久| 少妇粗大呻吟视频| 亚洲国产看品久久| 五月玫瑰六月丁香| 一夜夜www| 午夜免费激情av| 免费在线观看成人毛片| 国产成人av激情在线播放| 国产精品乱码一区二三区的特点| 欧美日韩黄片免| 亚洲国产看品久久| 国产精品自产拍在线观看55亚洲| 午夜精品久久久久久毛片777| 国产精品 欧美亚洲| 白带黄色成豆腐渣| 999精品在线视频| 少妇人妻一区二区三区视频| 日韩三级视频一区二区三区| 一夜夜www| 久久精品国产99精品国产亚洲性色| 日本一本二区三区精品| 国产精品99久久99久久久不卡| 午夜福利在线在线| 久久精品aⅴ一区二区三区四区| 国产一区二区三区在线臀色熟女| 男插女下体视频免费在线播放| 99热这里只有精品一区 | 两人在一起打扑克的视频| 国产激情久久老熟女| 亚洲午夜理论影院| 伊人久久大香线蕉亚洲五| 香蕉av资源在线| 搡老妇女老女人老熟妇| www.www免费av| 欧洲精品卡2卡3卡4卡5卡区| 99re在线观看精品视频| 亚洲精品国产精品久久久不卡| 久久精品91无色码中文字幕| 亚洲精品国产一区二区精华液| 成人永久免费在线观看视频| 国产精品1区2区在线观看.| 悠悠久久av| 国产视频一区二区在线看| 国产亚洲精品第一综合不卡| 国产91精品成人一区二区三区| 国产精品av视频在线免费观看| 最近最新中文字幕大全免费视频| 99在线视频只有这里精品首页| 日韩欧美国产在线观看| 中文资源天堂在线| 我的老师免费观看完整版| 18禁黄网站禁片免费观看直播| 变态另类丝袜制服| 最近视频中文字幕2019在线8| 日韩av在线大香蕉| 老司机午夜十八禁免费视频| 成人国语在线视频| 九色国产91popny在线| 黑人操中国人逼视频| 亚洲专区国产一区二区| 亚洲中文字幕一区二区三区有码在线看 | 夜夜看夜夜爽夜夜摸| 村上凉子中文字幕在线| ponron亚洲| av国产免费在线观看| 在线永久观看黄色视频| 丰满的人妻完整版| 亚洲熟妇熟女久久| 免费搜索国产男女视频| 久久这里只有精品19| 日日干狠狠操夜夜爽| 美女 人体艺术 gogo| 色综合欧美亚洲国产小说| 国产高清videossex| 日日爽夜夜爽网站| 一本综合久久免费| 久久香蕉精品热| ponron亚洲| 不卡一级毛片| 久久精品人妻少妇| 婷婷六月久久综合丁香| 91麻豆精品激情在线观看国产| 亚洲av日韩精品久久久久久密| 久久精品91无色码中文字幕| 99在线视频只有这里精品首页| 一进一出抽搐动态| 欧美色视频一区免费| 久久久国产成人精品二区| 法律面前人人平等表现在哪些方面| 国产乱人伦免费视频| 日韩精品免费视频一区二区三区| 亚洲一卡2卡3卡4卡5卡精品中文| 一本综合久久免费| 国产91精品成人一区二区三区| 无人区码免费观看不卡| 777久久人妻少妇嫩草av网站| 99精品欧美一区二区三区四区| 1024手机看黄色片| 色老头精品视频在线观看| 中文字幕人妻丝袜一区二区| 精品久久久久久成人av| 久久精品人妻少妇| 中国美女看黄片| 男男h啪啪无遮挡| 日韩 欧美 亚洲 中文字幕| 在线观看免费日韩欧美大片| 欧美激情久久久久久爽电影| 国产精品日韩av在线免费观看| 狂野欧美激情性xxxx| 欧美三级亚洲精品| 国产高清有码在线观看视频 | 久久香蕉精品热| 麻豆国产97在线/欧美 | 啦啦啦免费观看视频1| 久久午夜亚洲精品久久| 欧美精品亚洲一区二区| 国产一区二区激情短视频| 人妻久久中文字幕网| 国产精品1区2区在线观看.| 琪琪午夜伦伦电影理论片6080| 国产v大片淫在线免费观看| 亚洲人成网站在线播放欧美日韩| 极品教师在线免费播放| 午夜精品一区二区三区免费看| 人人妻人人澡欧美一区二区| 麻豆成人午夜福利视频| 国产精品99久久99久久久不卡| 国产亚洲欧美在线一区二区| 级片在线观看| 亚洲成人精品中文字幕电影| 午夜精品久久久久久毛片777| 在线十欧美十亚洲十日本专区| 18禁国产床啪视频网站| 99久久综合精品五月天人人| 亚洲专区中文字幕在线| 又大又爽又粗| 日韩国内少妇激情av| 欧美黄色片欧美黄色片| 91麻豆av在线| 久久精品人妻少妇| 国产av又大| 欧美激情久久久久久爽电影| 99国产综合亚洲精品| 日韩欧美国产在线观看| 一a级毛片在线观看| 最近在线观看免费完整版| 老司机深夜福利视频在线观看| 十八禁网站免费在线| 首页视频小说图片口味搜索| 久久久久久人人人人人| 又大又爽又粗| 亚洲色图av天堂| 琪琪午夜伦伦电影理论片6080| 丰满人妻熟妇乱又伦精品不卡| 99国产极品粉嫩在线观看| 一边摸一边抽搐一进一小说| 欧美日本视频| 久久久水蜜桃国产精品网| 国产精品久久电影中文字幕| 日韩免费av在线播放| 母亲3免费完整高清在线观看| 99在线人妻在线中文字幕| 亚洲欧美日韩高清专用| 亚洲专区国产一区二区| 欧美成人性av电影在线观看| 好看av亚洲va欧美ⅴa在| 国产免费av片在线观看野外av| 国产日本99.免费观看| 国产亚洲精品久久久久久毛片| 少妇裸体淫交视频免费看高清 | 日韩欧美国产在线观看| 在线观看www视频免费| 国产一区二区在线av高清观看| 99久久国产精品久久久| 久久精品亚洲精品国产色婷小说| 99久久精品热视频| a级毛片a级免费在线| 蜜桃久久精品国产亚洲av| 免费在线观看影片大全网站| 国产亚洲欧美在线一区二区| 国产精品亚洲av一区麻豆| 欧美性长视频在线观看| 亚洲,欧美精品.| 国产成人av教育| 好看av亚洲va欧美ⅴa在| 搡老岳熟女国产| 亚洲精品久久国产高清桃花| 丰满人妻熟妇乱又伦精品不卡| 国产乱人伦免费视频| 国产蜜桃级精品一区二区三区| 后天国语完整版免费观看| 看片在线看免费视频| 无遮挡黄片免费观看| 亚洲黑人精品在线| 精品久久久久久久久久久久久| 成人特级黄色片久久久久久久| 麻豆国产97在线/欧美 | 欧美三级亚洲精品| 国产91精品成人一区二区三区| 欧美成人一区二区免费高清观看 | 中出人妻视频一区二区| 最新美女视频免费是黄的| 欧美性长视频在线观看| 男人舔奶头视频| 舔av片在线| 最新在线观看一区二区三区| 国产精品99久久99久久久不卡| 午夜免费观看网址| 毛片女人毛片| netflix在线观看网站| 午夜视频精品福利| 免费看a级黄色片| 国产野战对白在线观看| 亚洲成人国产一区在线观看| 精品国内亚洲2022精品成人| 色老头精品视频在线观看| 日韩三级视频一区二区三区| 久久九九热精品免费| 久久午夜综合久久蜜桃| 日韩免费av在线播放| 91成年电影在线观看| 老司机午夜十八禁免费视频| 国产午夜精品论理片| 69av精品久久久久久| 桃红色精品国产亚洲av| 成人三级做爰电影| 国产亚洲av高清不卡| 国产精品一区二区三区四区久久| 毛片女人毛片| 日韩大尺度精品在线看网址| 老熟妇仑乱视频hdxx| 90打野战视频偷拍视频| 久久久精品国产亚洲av高清涩受| 身体一侧抽搐| 十八禁人妻一区二区| 日韩精品中文字幕看吧| 欧美zozozo另类| 欧美日本视频| 99国产综合亚洲精品| 成人精品一区二区免费| 午夜福利免费观看在线| 看片在线看免费视频| 亚洲av成人av| 日日夜夜操网爽| 亚洲熟妇中文字幕五十中出| 免费在线观看日本一区| 国产精品一区二区三区四区久久| 人妻丰满熟妇av一区二区三区| 久久精品国产亚洲av香蕉五月| 久久精品国产99精品国产亚洲性色| 欧美又色又爽又黄视频| 美女 人体艺术 gogo| 午夜福利高清视频| 麻豆成人午夜福利视频| 日韩免费av在线播放| 国产欧美日韩一区二区精品| 国产高清视频在线播放一区| 一进一出抽搐动态| 此物有八面人人有两片| 国产精品美女特级片免费视频播放器 | 欧美日本视频| 精品国产乱码久久久久久男人| 夜夜躁狠狠躁天天躁| 日韩欧美三级三区| 天堂影院成人在线观看| 日韩 欧美 亚洲 中文字幕| 狂野欧美激情性xxxx| 午夜福利18| 成年免费大片在线观看| 欧美日本亚洲视频在线播放| 欧美3d第一页| 亚洲自拍偷在线| 国产97色在线日韩免费| 美女大奶头视频| 亚洲人成伊人成综合网2020| 午夜影院日韩av| 国产亚洲欧美98| 国产亚洲精品久久久久久毛片| 麻豆av在线久日| 黄色成人免费大全| 久久天躁狠狠躁夜夜2o2o| 亚洲精品一卡2卡三卡4卡5卡| 中文字幕人成人乱码亚洲影| 青草久久国产| 日日爽夜夜爽网站| 国产亚洲精品久久久久久毛片| 女生性感内裤真人,穿戴方法视频| 国产成人欧美在线观看| 一级毛片高清免费大全| www.999成人在线观看| 丰满人妻熟妇乱又伦精品不卡| 欧美日韩黄片免| 成在线人永久免费视频| 欧美中文综合在线视频| 一区二区三区激情视频| 亚洲欧美一区二区三区黑人| 女人爽到高潮嗷嗷叫在线视频| 美女高潮喷水抽搐中文字幕| 一进一出抽搐动态| 国产亚洲精品久久久久久毛片| 日韩av在线大香蕉| 两性午夜刺激爽爽歪歪视频在线观看 | 亚洲成a人片在线一区二区| 麻豆久久精品国产亚洲av| 免费搜索国产男女视频| 99国产精品一区二区三区| 久久久精品欧美日韩精品| 欧美久久黑人一区二区| 久久精品aⅴ一区二区三区四区| av片东京热男人的天堂| 成人特级黄色片久久久久久久| 亚洲av熟女| 亚洲中文日韩欧美视频| 免费在线观看完整版高清| svipshipincom国产片| 国产精品久久久久久亚洲av鲁大| a级毛片在线看网站| 国产熟女xx| 88av欧美| 精品久久蜜臀av无| 午夜影院日韩av| bbb黄色大片| 老汉色∧v一级毛片| 国产成人影院久久av| 亚洲欧美日韩东京热| www.999成人在线观看| 国产高清videossex| 国产一区二区在线观看日韩 | 精品国产超薄肉色丝袜足j| 国产伦人伦偷精品视频| 黑人欧美特级aaaaaa片| 亚洲国产精品999在线| 国产亚洲欧美98| 午夜福利高清视频| 后天国语完整版免费观看| 久久国产精品影院| 在线观看美女被高潮喷水网站 | 国产激情偷乱视频一区二区| 俺也久久电影网| 亚洲精品av麻豆狂野| 宅男免费午夜| 婷婷丁香在线五月| 男人舔奶头视频| 欧美成人一区二区免费高清观看 | 欧美成人午夜精品| 日韩av在线大香蕉| 国产精品乱码一区二三区的特点| 免费看美女性在线毛片视频| 亚洲成人久久爱视频| 国产99白浆流出| 国产精品久久视频播放| 757午夜福利合集在线观看| 黄频高清免费视频| 色综合婷婷激情| 久久精品综合一区二区三区| 制服人妻中文乱码| 午夜福利欧美成人| 精品一区二区三区四区五区乱码| 欧美成人午夜精品| 欧美性猛交黑人性爽| 国产探花在线观看一区二区| 国产主播在线观看一区二区| 狂野欧美白嫩少妇大欣赏| 一边摸一边做爽爽视频免费| 俄罗斯特黄特色一大片| 精品久久久久久久人妻蜜臀av| 国产一区二区在线av高清观看| 国产精品一区二区免费欧美| 免费av毛片视频| 国产97色在线日韩免费| 免费在线观看影片大全网站| 午夜福利视频1000在线观看| 黑人巨大精品欧美一区二区mp4| 中亚洲国语对白在线视频| 国产伦在线观看视频一区| 午夜福利免费观看在线| 男男h啪啪无遮挡| 19禁男女啪啪无遮挡网站| 狂野欧美激情性xxxx| 精品人妻1区二区| 别揉我奶头~嗯~啊~动态视频| 国产亚洲av高清不卡| 99国产精品一区二区蜜桃av| 99国产精品99久久久久| 国产精品一区二区三区四区久久| 中文在线观看免费www的网站 | 欧美日韩福利视频一区二区| 一级黄色大片毛片| 亚洲黑人精品在线| 久久久久国产精品人妻aⅴ院| 亚洲九九香蕉| 亚洲一区二区三区不卡视频| 亚洲无线在线观看| 亚洲人成网站高清观看| 男女做爰动态图高潮gif福利片| 久久久国产成人精品二区| 天天躁狠狠躁夜夜躁狠狠躁| 精品熟女少妇八av免费久了| 99久久久亚洲精品蜜臀av| 日本一二三区视频观看| 亚洲精品一卡2卡三卡4卡5卡| 亚洲aⅴ乱码一区二区在线播放 | 国产欧美日韩精品亚洲av| 高潮久久久久久久久久久不卡| 欧美在线黄色| 国产熟女午夜一区二区三区| 日韩中文字幕欧美一区二区| 亚洲国产精品成人综合色| 一区二区三区国产精品乱码| 国产午夜精品久久久久久| 亚洲av成人精品一区久久| 亚洲成人国产一区在线观看| 日韩欧美在线二视频| 久久亚洲精品不卡| 亚洲欧美精品综合久久99| 国产在线观看jvid| av福利片在线| 妹子高潮喷水视频| 久久午夜亚洲精品久久| 一区二区三区激情视频| 精品久久久久久久末码| 99国产精品一区二区三区| 亚洲性夜色夜夜综合| 天堂影院成人在线观看| 在线视频色国产色| 午夜老司机福利片| 国产三级中文精品| 很黄的视频免费| 熟女电影av网| 麻豆久久精品国产亚洲av| 久久香蕉国产精品| 好看av亚洲va欧美ⅴa在| 精品国产乱码久久久久久男人| 久久精品亚洲精品国产色婷小说| 国产高清视频在线观看网站| 日本在线视频免费播放| 婷婷六月久久综合丁香| 久久国产精品人妻蜜桃| 黄色视频不卡| 真人做人爱边吃奶动态| 国产一区二区三区在线臀色熟女| 日韩欧美在线乱码| 国产午夜精品久久久久久| 啦啦啦韩国在线观看视频| 国产精品,欧美在线| 制服人妻中文乱码| 久久精品综合一区二区三区| 看片在线看免费视频| 亚洲欧美一区二区三区黑人| 国产精品亚洲一级av第二区| 真人一进一出gif抽搐免费| 婷婷精品国产亚洲av在线| 成熟少妇高潮喷水视频| 国产高清激情床上av| 淫妇啪啪啪对白视频| 色综合站精品国产| 成人精品一区二区免费| 国产三级黄色录像| 丁香六月欧美| 日本免费a在线| 日韩国内少妇激情av| 色播亚洲综合网| 国产黄片美女视频| 国产精品 国内视频| 欧美成人午夜精品| 久久人妻福利社区极品人妻图片| av视频在线观看入口| 精品国产乱子伦一区二区三区| 黄片小视频在线播放| 国产精品一区二区免费欧美| 久久精品影院6| 国产aⅴ精品一区二区三区波| 亚洲激情在线av| 日本一本二区三区精品| 美女高潮喷水抽搐中文字幕| www.熟女人妻精品国产| 日韩精品免费视频一区二区三区| 久久伊人香网站| 亚洲国产精品sss在线观看| 中出人妻视频一区二区| 美女午夜性视频免费| 欧洲精品卡2卡3卡4卡5卡区| 他把我摸到了高潮在线观看| 法律面前人人平等表现在哪些方面| 国产一区二区在线观看日韩 | √禁漫天堂资源中文www| 欧美又色又爽又黄视频| 亚洲精品中文字幕一二三四区| 国产免费男女视频| 国产黄色小视频在线观看| 9191精品国产免费久久| 国产精品爽爽va在线观看网站| 亚洲中文日韩欧美视频| 国产三级黄色录像| 人成视频在线观看免费观看| 天天一区二区日本电影三级| 最近视频中文字幕2019在线8| 亚洲国产日韩欧美精品在线观看 | 久久久久久久久免费视频了| av在线播放免费不卡| 亚洲国产中文字幕在线视频| 草草在线视频免费看| www国产在线视频色| 国产真人三级小视频在线观看| bbb黄色大片| 老熟妇仑乱视频hdxx| 桃色一区二区三区在线观看| 97碰自拍视频| 麻豆成人午夜福利视频| 18禁观看日本| av片东京热男人的天堂| 美女午夜性视频免费| 天堂影院成人在线观看| 波多野结衣高清作品| 国产精品一区二区免费欧美| 亚洲av日韩精品久久久久久密| 亚洲欧美激情综合另类| 国产精品乱码一区二三区的特点| 日韩大码丰满熟妇| 伊人久久大香线蕉亚洲五| 欧美中文日本在线观看视频| 久久婷婷人人爽人人干人人爱|