• <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 ?

    A large eddy simulation of flows around an underwater vehicle model using an immersed boundary method

    2017-01-06 08:47:03ShizhoWngBeijiShiYuhngLiGuoweiHe

    Shizho Wng,Beiji Shi,b,Yuhng Li,b,Guowei He,b,?

    aThe State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China

    bSchool of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

    A large eddy simulation of flows around an underwater vehicle model using an immersed boundary method

    Shizhao Wanga,Beiji Shia,b,Yuhang Lia,b,Guowei Hea,b,?

    aThe State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China

    bSchool of Engineering Sciences,University of Chinese Academy of Sciences,Beijing 100049,China

    H I G H L I G H T S

    ·The velocity self-similarity of wake is predicted by using large-eddy simulation.

    ·Diffuse interface immersed boundary method is coupled with large eddy simulation.

    ·The flow solver with IB method shows nearly linear parallel scalabilities.

    A R T I C L E I N F O

    Article history:

    Received 2 November 2016

    Accepted 7 November 2016

    Available online 22 November 2016

    Underwater vehicle

    SUBOFF

    Immersed boundary method

    Large eddy simulation

    Adaptive mesh refinement

    A large eddy simulation(LES)of the flows around an underwater vehicle model at intermediate Reynolds numbers is performed. The underwater vehicle model is taken as the DARPA SUBOFF with full appendages, where the Reynolds number based on the hull length is 1.0×105.An immersed boundary method based on the moving-least-squares reconstruction is used to handle the complex geometric boundaries.The adaptive mesh refinement is utilized to resolve the flows near the hull.The parallel scalabilities of the flow solver are tested on meshes with the number of cells varying from 50 million to 3.2 billion.The parallel solver reaches nearly linear scalability for the flows around the underwater vehicle model.The present simulation captures the essential features of the vortex structures near the hull and in the wake. Both of the time-averaged pressure coefficients and streamwise velocity profiles obtained from the LES areconsistent with the characteristics of the flows pass an appended axisymmetric body.The code efficiency and its correct predictions on flow features allow us to perform the full-scale simulations on tens of thousands of cores with billions of grid points for higher-Reynolds-number flows around the underwater vehicles.

    ?2016 The Authors.Published by Elsevier Ltd on behalf of The Chinese Society of Theoretical and Applied Mechanics.This is an open access article under the CC BY-NC-ND license(http:// creativecommons.org/licenses/by-nc-nd/4.0/).

    The modern underwater vehicles have untraditional appendages to achieve high maneuverability at intermediate to high Reynolds numbers[1,2].This raises two challenges for a full-scale simulation of the flows around the underwater vehicles:the first one is to handle the complex geometric and moving boundaries; the second one is to calculate the characteristics of viscous flows near the boundaries and in the wake[3,4].Recently,the immersed boundary(IB)method in combination with large eddy simulation has been developed to simulate turbulent flows with complex geometric and moving boundaries[5–7].The IB method is a nonbody conformal method and circumvents the generation of bodyfitting grids,where an artificial force is added to the Navier–Stokes equations to represent the boundary effect on flows,This method has been widely used in cardiovascular flows,bio-locomotion,and wind-turbines[8–10]with great successes.

    Recently,Posa and Balaras[11]have used the hybrid immersed boundary method and large eddy simulation to simulate the wake of an axisymmetric body with appendages.They choose a sharp interface IB method to simulate the turbulent wakes.The sharp interface IB method treats the boundaries on the Eulerian meshes by using complex local flow field reconstructions or the cut cell techniques,which are usually time consuming for a body with complex geometry.Instead of reconstructing the cell near boundaries,the diffuse interface IB method spreads the effects of solid boundaries onto a band of cells near boundaries.This method ensures the efficiency and robustness of the implementation. The diffuse interface IB method has been successfully utilized in laminar flows,but the grid resolution near the wall often limits its application to turbulent flows.The diffuse interface IBmethodcannotrefinethegridonlyalongthewallnormaldirection, since it is a non-body conformal method.The adaptive mesh refinement is an efficient way to locally refine the mesh,and can be utilized to reduce the number of mesh cells in the diffusive IB method.Furthermore,the diffusive IB method needs to be combinedwiththelargeeddysimulationtoavoidresolvingallflow structures in turbulence.However,the combinations of the diffuse interface IB method,adaptive mesh refinement,and large eddy simulationmightnotguaranteetheiraccuracyandefficiency,since they have different theoretical bases and numerical implement techniques.The simulations of turbulent flows with complex geometric boundaries are required to investigate the validation and efficiency of the combinations of the diffuse interface IB method,adaptive mesh refinement,and the large eddy simulation.

    Fig.1.DARPA SUBOFF with full appendages(a)and the Lagrangian mesh near the sail(b)and fins(c).

    The objective of the present work is to investigate the validation and efficiency of the hybrid diffuse interface IB method, adaptive mesh refinement and large eddy simulation for turbulent flows with complex geometric boundaries.The advantages and disadvantages of the method will also be reported.The simulated model is taken as the flows around an underwater vehicle.We will use the moving-least-squares reconstruction on a block structured mesh with the adaptive mesh refinement technique.We will first introduce the underwater vehicle model and the numerical method that will be used.The efficiency of our code will be discussed and numerical results will be presented.Finally,we will summarize the results and future work.

    In the present work,the DARPA SUBOFF is used as the underwater vehicle model.The model consists of an axisymmetric hull,a sail and four fins,as shown in Fig.1.The axisymmetric hull is composed of a bow forebody,a parallel middle body section,and a curved stern.The hull has a maximum diameterDand a lengthL/D=8.6.The details of the used model can be found in the Ref.[12].The appendages raise the challenges in both handling with the complex geometric boundaries and capturing the flow features(such as boundary layer,junction flows,tip flows,and their interactions),which provide a sufficient complex model for investigating the capability of the diffuse interface IB method in combination of large eddy simulation and the adaptive mesh refinement.

    Table 1 Strong scalability of the flow solver on a mesh of about 50 million cells.The notations‘Ncore’and‘Ncell’denote the number of cores and the number of cells, respectively.‘Tstep’denotes the wall-clock time cost per step.

    Table 2 Weak scalability of the flow solver with a mesh of about 0.26 million cells per core. The notations‘Ncore’and‘Ncell’denote the number of cores and the number of cells,respectively.‘Tstep’denotes the wall-clock time cost per step.

    The present work focuses on deep-submergence underwater vehicle,where the effects of free surface on the flows near the model are ignored.The flows around the model are governed by theNavier–Stokesequationsforsinglephaseincompressibleflows. The governing equations for large eddy simulation are given by where?ui(i=1,2,3)and?pare the filtered velocity components and pressure,respectively.The sub-grid stresses?τijis represented by the wall-adapting local eddy-viscosity model withCw= 0.6[13].fi(i=1,2,3)are the volume forces that represent the effects of boundaries on the flows in the IB method.Re is the Reynolds number.

    Equations(1)and(2)are discretized on a Cartesian Eulerian mesh and solved by using a projection method.The secondorder central difference is used for the spatial derivatives,and the second-order Adams–Bashforth method is used for the time advance.Figure 1 presents the Lagrangian mesh near the sail and fins on the SUBOFF.A diffuse interface IB method based on the moving-least-squares reconstruction is used to represent the effects of the model surface on flows.[14,15].The computational domain is[-4.3D,4.3D]×[-4.3D,4.3D]×[-2.6D,23.2D].The uniformupstreamflowboundaryconditionisusedattheinlet,and convective outflow boundary condition is used at the outlet.The non-slip boundary conditions are used on the immersed surfaces. The slip boundary conditions are used at the outer boundaries.A trip wire is located at the 0.25Ddownstream of the model nose. The Reynolds number based on the upstream flow velocity and the length of the model isReL=U∞L/ν=1.0×105,corresponding to a Reynolds number based on the maximum diameter ofReD=U∞D(zhuǎn)/ν≈ 1.16×104.HereU∞is the uniform free stream flow velocity andνis the kinematic viscosity of the fluid.

    In the present simulation,we utilize the block-structured mesh with adaptive mesh refinement.The parallel scalability of the flow solver is tested on meshes with different levels of refinement. Table 1 gives the wall-clock time cost of the flow solver on a mesh of about 50 million cells,which decreases as increasing the number of cores;Table 2 gives the wall-clock time cost of the flow solver on a mesh of about 0.26 million cells per core,which keeps nearly constant as increasing the number of cores.They show the strong and weak scalabilities of the parallel solver,respectively. In this letter,we report the preliminary results on the mesh of 50 million cells with a minimum grid length ofdh=0.0336. The minimum grid length is about 300 wall units,where the wall unit is estimated based on the turbulent boundary layer over a flat plate.The grid independence is checked to guarantee the sufficient resolution for the time-averaged pressure coefficient on the hull and the streamwise velocity profiles in the wake.It is worth to mention that the grid resolution is not fine enough to directly calculate the wall shear stress.A wall model is usually utilized to correctly obtain the wall shear stress in the LES with such a near-wallgridresolution.Wecalculatethetime-averagedpressure coefficient on the hull and the streamwise velocity profiles in the wake in the present letter.The simulations with wall models and the distribution of wall shear stress will be carried on in future.

    Fig.2.(Color Online)The snapshots of the instantaneous vorticity magnitude(a,c)and pressure(b)at the symmetric plane(x=0).The notations‘TV’and‘BL’denote‘Tip Vortex’and‘Boundary Layer’,respectively.

    Figure 2 plots the contours of vorticity magnitude and pressure at the symmetric plane(x=0).The essential features of flows can be observed,such as boundary layer,tip flows,shear layers and their interactions:(1)the pressure increases in front of the hull due to the decreasing velocities near the stagnation point at the nose;(2)the boundary layer develops from the stagnation point. The flow separates at the trip wire and reattaches to the hull in the rear of the trip wire;(3)the boundary layer and upstream flows interact with the leading edge of the sail,which causes a local pressure peak in front of the sail;(4)the tip flow origins from the top of the sail and moves downstream in the form of tip vortex;(5)the tip vortex(denoted as TV in Fig.2)interacts with the boundary layer(denoted as BL in Fig.2)in the middle of the hull;(6)the adverse pressure gradient occurs near the stern due to the contraction of hull and contributes to the boundary layer separation;(7)the boundary layer from the hull interacts with the fins,resulting in local pressure peaks in front of the fins;(8)the free shear layers shed from the fins and the hull are convected downstream into the wake;(9)the bimodal behavior of vorticity magnitudes can be observed in the wake,which is caused by the boundary layer separation and the interactions of the shear layers from both hull and fins.The pressure is consistent with the observed vortex structures[11,16,17],which can be found in the discussion on Fig.3.

    The distributions of the time-averaged pressure coefficients at the bottom and top meridians of the model are shown in Fig.3.The pressure coefficient is computed in terms of

    Fig.3.(Color Online)Time-averaged pressure coefficients on the top and bottom meridians of the model.

    where?p∞and 0.5ρU2∞are the static and dynamic pressures at the inlet,respectively.ρis the density of the fluid.The overall distribution of the time-averaged pressure coefficient is consistent with the experimental result of Jiménez et al.[16]and the numerical simulation of Posa and Balaras[11].The differences between the current simulation and the Refs.[11,16]are caused by the different Reynolds numbers.The Reynolds number in the present simulations isReL=U∞L/ν= 1.0× 105,which is only about 1/10 of those from the experiment(ReL=U∞L/ν= 1.1×106)[16]and the numerical simulation(ReL=U∞L/ν= 1.2×106)[11].The detailed features of the pressure coefficient are as follows:(1)the pressure coefficient has a maximum value at the stagnation point(z/L=0),and decreases sharply before it reaches the trip wire(0 <z/L< 0.03);(2)the pressure coefficient increases in the rear of the trip wire,and reaches a local maximum at the top meridian in front of the sail(0.03<z/L< 0.2).The present simulation has a lower pressure region right behind the trip wire.The low pressure is caused by the size of the trip wire,in addition to the low Reynolds number effects.The diameter of the trip wire in the present simulation is about 10 times as large as those in the previous experiment and numerical simulation[11,16],which ensures the boundary layer transition at a lower Reynolds number;(3)the pressure coefficient at the bottom meridian varies slowly in the middle of the hull(0.2 <z/L< 0.7),since there is a parallel section in the model;the pressure coefficient at the top meridian varies slowly only in the region 0.4<z/L< 0.7,because the wake of sail affects the pressure beforez/L=0.4;(4)The adversed pressure gradient appears near the stern(0.7 <z/L< 0.9). The pressure coefficient near the stern is higher than those in the Refs.[11,16].This is caused by the lower Reynolds number in the present simulation.The lower Reynolds number is corresponding to a thicker boundary layer along the hull.The thicker boundary layer reduces the effect of the geometry contraction of the hull; (5)the pressure coefficient reaches the local peak in front of the fins(z/L≈0.9),which corresponds to the interaction of boundary layers with fins.Notice that no fin is used in the experiment[16]. Instead, the full appendages are used in the present simulation.We also checked the effect of refinement levels on the distribution of pressure coefficients.The results show that the diffuse interface IB method reproduces the essential features of the distribution of pressure coefficient.

    Figure 4 plots the time-averaged streamwise velocity profiles in the wake.The time-averaged streamwise velocity is normalized bythelocaldefectvelocityu0andhalf-wakewidthl0,whichsatisfy the following power law[18],respectively,

    Fig.4.(Color Online)Self-similar behaviors of the time-averaged streamwise velocity profiles in the wake.The labels‘6D’,‘9D’,and‘12D’indicate the velocity profiles at 6D,9D,and 12D downstream from the model tail.

    whereA,B,andx0are the coefficients dependent on the behaviors of the flow.The coefficients in Eqs.(4)and(5)for the present simulations areA=0.902,B=0.245,andx0=1.908.The velocity defects at three different locations in the wake are selfsimilar,since they nearly collapse into one single curve at the scaled vertical distances.The time-averaged velocity profile in the side of the sail(y/l0>0)is lower than that in the experiment[16]. The lower time-averaged velocity profile is also reported by Posa and Balaras[11].This is caused by the blockage of the support in the experiment, since a long sail to support the model is used in the experiment.The time-averaged velocity defects without the effect of support are obtained by Jiménez et al.[16]and an analytical model for the axisymmetric wake provided by Pope[19]are also plotted in Fig.4.The velocity defects in the present simulation are consistent with the experimental and analytical results.

    In summary,the large eddy simulation of DARPA SUBOFF with the full appendages is performed by using a diffuse interface immersed boundary method.Particularly,the IB method is implemented through the moving-least-squares reconstruction and the block structured meshes with adaptive mesh refinement. The parallel scalabilities of the flow solver are tested on meshes at different levels of refinement with the total cells number varying from 50 million to 3.2 billion.It is shown that the parallel solver has the nearly linear strong and weak scalabilities for the present configuration.The numerical results provide the overall features of the flows near the hull surfaces and in the wake. The time-averaged pressure coefficients on the hull surface are consistent with the model configuration.The defects of time-averaged streamwise velocities exhibit the self-similarities as predicted by the power law.

    The diffuse interface IB method used in this work is robust and efficient for simulating intermediate Reynolds number flows aroundunderwatervehicles.However,itremainsagreatchallenge that the IB method is used to predict the shear stresses on hull surfaces.The shear stresses are dependent on the velocity gradients near surfaces so that the finer meshes in the wallnormal direction are needed.It is noted that the meshes in the IB method cannot be refined only in the wall-normal direction. Two possible approaches to overcome this defeat are to increase the grid numbers near wall and use the wall models.The nearly linear scalability of the present flow solver allows us to use tens of thousands of cores with billions of grid points in National Center of Supercomputer.Meanwhile,we will use the wall models for the IB method to reduce the computational cost and provide a feasible approach for the simulation-based studies of underwater vehicles.

    Acknowledgments

    This work was supported by the National Natural Science Foundation of China(11302238,11232011 and 11572331).The authors would like to acknowledge the support from the Strategic Priority Research Program(XDB22040104)and the Key Research Program of Frontier Sciences of the Chinese Academy of Sciences (QYZDJ-SSW-SYS002)and the National Basic Research Program of China(973 Program 2013CB834100:Nonlinear science).

    [1]P.R. Bandyopadhyay, Trends in biorobotic autonomous undersea vehicles, IEEE J. Ocean. Eng. 30 (2005) 109–139

    [2]X.C. Wu, Y.W. Wang, C.G. Huang, et al., An effective CFD approach for marine-vehicle maneuvering simulation based on the hybrid reference frames method, Ocean Eng. 109 (2015) 83–92.

    [3]Y.Yang,D.I.Pullin,Evolution of vortex-surface fields in viscous Taylor-Green and Kida-Pelz flows,J.Fluid Mech.685(2011)146–164.

    [4]Y.M.Zhao,Y.Yang,S.Y.Chen,Vortex reconnection in the late transition in channel flow,J.Fluid Mech.802(2016)R4.http://dx.doi.org/10.1017/jfm. 2016.492.

    [5]J.M.Yang,E.Balaras,An embedded-boundary formulation for large-eddy simulation of turbulent flows interacting with moving boundaries,J.Comput. Phys.215(2006)12–40.

    [6]X.L.Yang,G.W.He,X.Zhang,Large-eddy simulation of flows past a flapping airfoil using immersed boundary method,Sci.China Phys.Mech.Astron.53 (2010)1101–1108.

    [7]C.Yan,W.X.Huang,G.X.Cui,et al.,A ghost-cell immersed boundary method for large eddy simulation of flows in complex geometries,Int.J.Comput.Fluid Dyn.29(2015)1–14.

    [8]C.S.Peskin,The immersed boundary method,Acta Numer.11(2001)479–517.

    [9]R.Mittal,G.Iaccarino,Immersed boundary methods,Annu.Rev.Fluid Mech. 37(2005)239–261.

    [10]F.Sotiropoulos,X.L.Yang,Immersed boundary methods for simulating fluid–structure interaction,Prog.Aerosp.Sci.65(2014)1–21.

    [11]A.Posa,E.Balaras,A numerical investigation of the wake of an axisymmetric body with appendages,J.Fluid Mech.792(2016)470–498.

    [12]N.C.Groves,T.T.Huang,M.S.Chang,Geometric Characteristics of the DARPA SUBOFF Models,Tech.Rep.No.DTRC/SHD-1298-01,David Taylor Research Center,Bethesda,MD,1989.

    [13]F.Nicoud,F.Ducros,Subgrid-scale stress modelling based on the square of the velocity gradient tensor,Flow Turbul.Combust.62(1999)183–200.

    [14]M.Vanella,P.Rabenold,E.Balaras,A direct-forcing embedded-boundary method with adaptive mesh refinement for fluid–structure interaction problems,J.Comput.Phys.229(2010)6427–6449.

    [15]M.Vanella,E.Balaras,A moving-least-squares reconstruction for embeddedboundary formulations,J.Comput.Phys.228(2009)6617–6628.

    [16]J.M.Jiménez,R.T.Reynolds,A.J.Smits,The intermediate wake of a body of revolution at high Reynolds numbers,J.Fluid Mech.659(2010)516–539.

    [17]J.M.Jiménez,R.T.Reynolds,A.J.Smits,The effects of fins on the intermediate wake of a submarine model,J.Fluids Eng.132(2010)031102.

    [18]P.B.V.Johansson,W.George,M.Gourlay,Equilibrium similarity,effects of initial conditions and local Reynolds number on the axisymmetric wake,Phys. Fluids 15(2003)603–617.

    [19]S.B.Pope,Turbulent Flows,Cambridge University,United Kingdom,London, 2010(Chapter 5).

    ?Corresponding author.

    E-mail address:hgw@lnm.imech.ac.cn(G.He).

    http://dx.doi.org/10.1016/j.taml.2016.11.004

    2095-0349/?2016 The Authors.Published by Elsevier Ltd on behalf of The Chinese Society of Theoretical and Applied Mechanics.This is an open access article under the CC BY-NC-ND license(http://creativecommons.org/licenses/by-nc-nd/4.0/).

    *This article belongs to the Fluid Mechanics

    日本欧美视频一区| 少妇精品久久久久久久| 久久精品熟女亚洲av麻豆精品| 成人一区二区视频在线观看| 成人免费观看视频高清| 纵有疾风起免费观看全集完整版| 26uuu在线亚洲综合色| 精品久久久久久久久av| 免费观看性生交大片5| 精品人妻熟女av久视频| 国产深夜福利视频在线观看| 久久婷婷青草| 久久久精品免费免费高清| 性高湖久久久久久久久免费观看| 天堂中文最新版在线下载| 日韩伦理黄色片| 成人影院久久| 热99国产精品久久久久久7| 免费看av在线观看网站| av在线老鸭窝| 欧美一级a爱片免费观看看| 亚洲人成网站在线观看播放| 天堂中文最新版在线下载| 少妇人妻 视频| 一级二级三级毛片免费看| 久久久久网色| 国产乱人偷精品视频| 99re6热这里在线精品视频| 两个人的视频大全免费| 亚洲美女视频黄频| a级毛片免费高清观看在线播放| 91久久精品国产一区二区成人| 男人和女人高潮做爰伦理| 成年免费大片在线观看| 成年女人在线观看亚洲视频| 99精国产麻豆久久婷婷| 观看av在线不卡| 成人影院久久| 国产美女午夜福利| av在线老鸭窝| 色网站视频免费| 日本午夜av视频| 黑人猛操日本美女一级片| 亚洲四区av| 久久精品国产鲁丝片午夜精品| 不卡视频在线观看欧美| 国产av码专区亚洲av| 免费观看av网站的网址| 日韩国内少妇激情av| 欧美人与善性xxx| av.在线天堂| 精品国产三级普通话版| 亚洲不卡免费看| 亚洲欧美成人精品一区二区| 亚洲精品aⅴ在线观看| 国产成人免费观看mmmm| 欧美zozozo另类| 热re99久久精品国产66热6| 国产av一区二区精品久久 | 久久久午夜欧美精品| 777米奇影视久久| 精品一区二区免费观看| 一级毛片电影观看| 亚洲色图综合在线观看| 国产美女午夜福利| 亚洲第一av免费看| 色网站视频免费| 国产精品av视频在线免费观看| 色视频在线一区二区三区| 久久久色成人| 亚洲人成网站在线播| 亚洲在久久综合| 午夜福利网站1000一区二区三区| 一级毛片 在线播放| 亚洲欧美日韩无卡精品| 最近最新中文字幕免费大全7| 中国三级夫妇交换| 亚洲成人手机| 少妇人妻精品综合一区二区| 一级毛片aaaaaa免费看小| 亚洲国产高清在线一区二区三| 九九久久精品国产亚洲av麻豆| 久久国产亚洲av麻豆专区| 99热这里只有是精品在线观看| 日韩一区二区视频免费看| 亚洲欧美一区二区三区黑人 | 看非洲黑人一级黄片| 一级毛片久久久久久久久女| 水蜜桃什么品种好| 涩涩av久久男人的天堂| 色综合色国产| 精品久久久久久久久亚洲| 国产精品女同一区二区软件| 久久人人爽人人片av| 80岁老熟妇乱子伦牲交| 男的添女的下面高潮视频| 又粗又硬又长又爽又黄的视频| 日本欧美国产在线视频| 最近最新中文字幕大全电影3| 99视频精品全部免费 在线| 日本午夜av视频| 这个男人来自地球电影免费观看 | av国产精品久久久久影院| 欧美zozozo另类| 国产亚洲精品久久久com| 99久久人妻综合| 性高湖久久久久久久久免费观看| 精品国产三级普通话版| 久久韩国三级中文字幕| 中文字幕制服av| 十八禁网站网址无遮挡 | 2018国产大陆天天弄谢| 在现免费观看毛片| 青春草视频在线免费观看| 在线看a的网站| av又黄又爽大尺度在线免费看| 日本一二三区视频观看| 国产日韩欧美在线精品| 国产av精品麻豆| 一个人看视频在线观看www免费| 国产免费一级a男人的天堂| 91aial.com中文字幕在线观看| 国产亚洲91精品色在线| 高清欧美精品videossex| 国产日韩欧美亚洲二区| 大陆偷拍与自拍| 18禁裸乳无遮挡动漫免费视频| 亚洲四区av| 久久婷婷青草| 亚洲一区二区三区欧美精品| 亚洲精品国产成人久久av| 亚洲欧美日韩另类电影网站 | 一区在线观看完整版| 亚洲欧美日韩卡通动漫| 在线亚洲精品国产二区图片欧美 | 亚洲图色成人| av福利片在线观看| 日韩不卡一区二区三区视频在线| 久久午夜福利片| av黄色大香蕉| 一个人看的www免费观看视频| 成人一区二区视频在线观看| 国产精品.久久久| 91午夜精品亚洲一区二区三区| 亚洲国产av新网站| 国产高清国产精品国产三级 | 人人妻人人看人人澡| 亚洲精品自拍成人| 一级毛片久久久久久久久女| 欧美日韩亚洲高清精品| 亚洲久久久国产精品| 精华霜和精华液先用哪个| 毛片一级片免费看久久久久| 新久久久久国产一级毛片| 国产有黄有色有爽视频| 国产一区亚洲一区在线观看| 日韩欧美精品免费久久| av线在线观看网站| 久久久久久久久久久免费av| 亚洲欧美日韩无卡精品| 亚洲欧美日韩卡通动漫| 97在线人人人人妻| 天堂中文最新版在线下载| 有码 亚洲区| 久久精品国产亚洲网站| 亚洲最大成人中文| 精品熟女少妇av免费看| 精品一区二区免费观看| 热99国产精品久久久久久7| 日韩欧美一区视频在线观看 | 日韩一本色道免费dvd| 激情 狠狠 欧美| 免费看av在线观看网站| 伦理电影大哥的女人| 久久久久久久久大av| 亚洲av免费高清在线观看| h视频一区二区三区| 蜜臀久久99精品久久宅男| 日韩成人av中文字幕在线观看| 纯流量卡能插随身wifi吗| av福利片在线观看| 久久人人爽人人爽人人片va| 久久久久性生活片| 国产精品不卡视频一区二区| 日本av免费视频播放| 天天躁日日操中文字幕| 久久精品夜色国产| 99热这里只有是精品50| 国产精品一区二区在线观看99| 男女边摸边吃奶| 色视频在线一区二区三区| 直男gayav资源| 男女免费视频国产| 国产视频首页在线观看| 免费在线观看成人毛片| 久久久久久久久久成人| 视频区图区小说| 卡戴珊不雅视频在线播放| 晚上一个人看的免费电影| 中文资源天堂在线| 美女主播在线视频| 一区二区三区乱码不卡18| 成人综合一区亚洲| 亚洲激情五月婷婷啪啪| av在线播放精品| 中文字幕人妻熟人妻熟丝袜美| 国产免费一级a男人的天堂| 美女xxoo啪啪120秒动态图| 久久久久久人妻| 亚洲av日韩在线播放| 丰满迷人的少妇在线观看| 欧美日韩亚洲高清精品| 日本免费在线观看一区| 麻豆国产97在线/欧美| 建设人人有责人人尽责人人享有的 | av不卡在线播放| 亚洲精品一二三| 亚洲av国产av综合av卡| 97超视频在线观看视频| 亚洲精品日本国产第一区| 国产精品人妻久久久久久| 最新中文字幕久久久久| 成年人午夜在线观看视频| 小蜜桃在线观看免费完整版高清| 身体一侧抽搐| 一级二级三级毛片免费看| 成年av动漫网址| 麻豆成人av视频| 国产 一区精品| 一区二区三区免费毛片| av黄色大香蕉| 国产黄色免费在线视频| 91精品伊人久久大香线蕉| 国产成人精品一,二区| 亚洲精品日韩在线中文字幕| 国产精品精品国产色婷婷| 狠狠精品人妻久久久久久综合| 久久国产精品大桥未久av | 久久久国产一区二区| 日本黄色片子视频| 成人亚洲欧美一区二区av| 九色成人免费人妻av| 亚洲成人一二三区av| 亚洲成人av在线免费| 国产亚洲午夜精品一区二区久久| 亚洲精品中文字幕在线视频 | 欧美最新免费一区二区三区| 亚洲国产欧美人成| 国产美女午夜福利| 亚洲丝袜综合中文字幕| 免费大片黄手机在线观看| 国产精品偷伦视频观看了| a级毛片免费高清观看在线播放| 亚洲四区av| 狠狠精品人妻久久久久久综合| 黄色一级大片看看| 一区二区av电影网| 欧美xxxx黑人xx丫x性爽| 久热久热在线精品观看| 看免费成人av毛片| 国产 一区精品| 少妇猛男粗大的猛烈进出视频| 成年女人在线观看亚洲视频| 看非洲黑人一级黄片| 简卡轻食公司| 精品酒店卫生间| 国产男女内射视频| 特大巨黑吊av在线直播| 你懂的网址亚洲精品在线观看| 亚洲av欧美aⅴ国产| 国产精品爽爽va在线观看网站| 妹子高潮喷水视频| 久久精品国产亚洲av涩爱| 亚洲熟女精品中文字幕| 最近手机中文字幕大全| 91精品一卡2卡3卡4卡| 精品一区二区免费观看| 国产精品国产三级国产专区5o| 国产熟女欧美一区二区| 美女xxoo啪啪120秒动态图| 国产一区有黄有色的免费视频| 精品人妻视频免费看| 久久午夜福利片| 国产伦理片在线播放av一区| 成人国产av品久久久| av女优亚洲男人天堂| 看免费成人av毛片| 精品久久国产蜜桃| 亚洲av在线观看美女高潮| 日产精品乱码卡一卡2卡三| 亚洲精品国产av成人精品| 中文资源天堂在线| 久久久成人免费电影| 青青草视频在线视频观看| 免费看av在线观看网站| 亚洲欧美精品自产自拍| 国精品久久久久久国模美| 色视频在线一区二区三区| 国产成人精品一,二区| 3wmmmm亚洲av在线观看| 国产黄色视频一区二区在线观看| 国产白丝娇喘喷水9色精品| 多毛熟女@视频| 又爽又黄a免费视频| 亚洲真实伦在线观看| 热99国产精品久久久久久7| 国产精品一区二区三区四区免费观看| 成人特级av手机在线观看| 晚上一个人看的免费电影| 日韩人妻高清精品专区| 精品久久久久久久末码| 亚洲欧美成人精品一区二区| 国产一区亚洲一区在线观看| 久久久久久久国产电影| 亚洲精品视频女| 国语对白做爰xxxⅹ性视频网站| 人妻一区二区av| 少妇的逼好多水| 丝瓜视频免费看黄片| av网站免费在线观看视频| 天堂8中文在线网| 亚洲美女搞黄在线观看| 制服丝袜香蕉在线| 亚洲欧美日韩卡通动漫| kizo精华| 久久久国产一区二区| 伊人久久国产一区二区| freevideosex欧美| 男人和女人高潮做爰伦理| 亚洲色图av天堂| 在线观看国产h片| 在线观看一区二区三区激情| 亚洲欧美成人综合另类久久久| 日本黄色片子视频| 久久久久久九九精品二区国产| 一区二区三区免费毛片| 不卡视频在线观看欧美| 男女国产视频网站| 国产v大片淫在线免费观看| 老司机影院毛片| 国产男人的电影天堂91| 亚洲四区av| 老师上课跳d突然被开到最大视频| 高清午夜精品一区二区三区| 99久久中文字幕三级久久日本| 亚洲国产最新在线播放| 国产又色又爽无遮挡免| 精品一区二区免费观看| 晚上一个人看的免费电影| 午夜福利在线在线| 麻豆成人午夜福利视频| 精品国产露脸久久av麻豆| 黄色怎么调成土黄色| a级一级毛片免费在线观看| 久久久久精品久久久久真实原创| 韩国高清视频一区二区三区| 日韩欧美 国产精品| 夜夜骑夜夜射夜夜干| h日本视频在线播放| 搡老乐熟女国产| 热re99久久精品国产66热6| 熟女电影av网| 在线观看国产h片| 欧美高清性xxxxhd video| 国产一区二区三区av在线| 国产精品一区www在线观看| 欧美区成人在线视频| 少妇猛男粗大的猛烈进出视频| 99国产精品免费福利视频| 欧美少妇被猛烈插入视频| 久久精品国产鲁丝片午夜精品| 91aial.com中文字幕在线观看| 亚洲精品第二区| 国产免费福利视频在线观看| 午夜老司机福利剧场| 五月开心婷婷网| 青青草视频在线视频观看| 午夜视频国产福利| www.色视频.com| 精品99又大又爽又粗少妇毛片| 国产精品偷伦视频观看了| 免费黄色在线免费观看| 夜夜看夜夜爽夜夜摸| 日韩av免费高清视频| 国产无遮挡羞羞视频在线观看| 日韩,欧美,国产一区二区三区| 久久久久久久久大av| 午夜激情福利司机影院| 少妇高潮的动态图| 一级二级三级毛片免费看| 午夜视频国产福利| 少妇的逼好多水| 国产免费又黄又爽又色| 国产精品一及| av在线app专区| 成人国产麻豆网| 亚洲av不卡在线观看| 国产精品成人在线| 麻豆乱淫一区二区| 国产乱人视频| 国产精品一区www在线观看| 高清黄色对白视频在线免费看 | 国产人妻一区二区三区在| 亚洲av日韩在线播放| 2021少妇久久久久久久久久久| 国产av码专区亚洲av| 国产高清有码在线观看视频| 在线播放无遮挡| 欧美另类一区| 久久这里有精品视频免费| 啦啦啦在线观看免费高清www| 欧美极品一区二区三区四区| av网站免费在线观看视频| 亚洲婷婷狠狠爱综合网| 亚洲欧美日韩东京热| 我要看日韩黄色一级片| 欧美高清成人免费视频www| 色哟哟·www| 久久国产精品男人的天堂亚洲 | 亚洲成人一二三区av| 久久99蜜桃精品久久| 免费在线观看成人毛片| 2022亚洲国产成人精品| 亚洲欧美一区二区三区国产| 国产女主播在线喷水免费视频网站| 99久久精品国产国产毛片| 亚洲电影在线观看av| 一区二区三区免费毛片| 国产男女超爽视频在线观看| 91久久精品国产一区二区成人| 国产欧美亚洲国产| 18禁在线播放成人免费| 久热这里只有精品99| 草草在线视频免费看| 久久99热6这里只有精品| 两个人的视频大全免费| 久久6这里有精品| 涩涩av久久男人的天堂| 亚洲欧美日韩无卡精品| 成年免费大片在线观看| 黄片无遮挡物在线观看| 成人二区视频| av播播在线观看一区| 国产乱来视频区| 男人舔奶头视频| 国产乱来视频区| 街头女战士在线观看网站| 麻豆精品久久久久久蜜桃| 自拍偷自拍亚洲精品老妇| 热re99久久精品国产66热6| 欧美日韩在线观看h| 人妻系列 视频| 久久99蜜桃精品久久| 国产无遮挡羞羞视频在线观看| 日韩制服骚丝袜av| 久久久色成人| 交换朋友夫妻互换小说| 国产精品久久久久久精品电影小说 | 免费久久久久久久精品成人欧美视频 | 在线观看人妻少妇| 97超视频在线观看视频| 一级爰片在线观看| 精品久久久久久电影网| 国产深夜福利视频在线观看| 亚洲伊人久久精品综合| 97在线人人人人妻| av免费在线看不卡| 男人狂女人下面高潮的视频| 亚洲精品日韩在线中文字幕| 亚洲四区av| 高清黄色对白视频在线免费看 | 直男gayav资源| 国产精品一及| 免费少妇av软件| 亚洲国产欧美人成| 国产又色又爽无遮挡免| 成人漫画全彩无遮挡| 亚洲久久久国产精品| 久久精品久久精品一区二区三区| 国产在线视频一区二区| 女人十人毛片免费观看3o分钟| 欧美激情极品国产一区二区三区 | 老熟女久久久| 一级毛片 在线播放| 成人美女网站在线观看视频| 少妇的逼好多水| 国产成人午夜福利电影在线观看| 激情 狠狠 欧美| 国产探花极品一区二区| 卡戴珊不雅视频在线播放| 99精国产麻豆久久婷婷| av不卡在线播放| 精品人妻偷拍中文字幕| 久久精品夜色国产| 亚洲美女黄色视频免费看| 国产精品久久久久久久久免| 亚洲精品日韩av片在线观看| 国产精品蜜桃在线观看| 九九久久精品国产亚洲av麻豆| 国产亚洲av片在线观看秒播厂| 久久久久久伊人网av| 又黄又爽又刺激的免费视频.| 亚洲精品乱久久久久久| 一级毛片aaaaaa免费看小| 国产高清国产精品国产三级 | 成人漫画全彩无遮挡| 欧美日本视频| 一级毛片电影观看| av专区在线播放| 国产亚洲欧美精品永久| av在线老鸭窝| 丰满人妻一区二区三区视频av| 直男gayav资源| 日韩制服骚丝袜av| 国产乱人偷精品视频| 久久精品久久久久久噜噜老黄| 久久久久性生活片| freevideosex欧美| 国产精品99久久99久久久不卡 | 美女内射精品一级片tv| 熟女电影av网| 丝袜脚勾引网站| 亚洲欧美精品专区久久| 免费黄网站久久成人精品| 99热网站在线观看| 成人美女网站在线观看视频| 丰满乱子伦码专区| 伦精品一区二区三区| 国产精品久久久久久av不卡| 精品熟女少妇av免费看| 少妇人妻精品综合一区二区| 中文欧美无线码| 丝瓜视频免费看黄片| 亚洲自偷自拍三级| 久久久精品免费免费高清| 我要看日韩黄色一级片| 精品酒店卫生间| 春色校园在线视频观看| 日韩av不卡免费在线播放| 国产亚洲精品久久久com| 夫妻性生交免费视频一级片| 久久国内精品自在自线图片| 在线天堂最新版资源| 日韩免费高清中文字幕av| 在线天堂最新版资源| 麻豆成人午夜福利视频| 自拍偷自拍亚洲精品老妇| 高清毛片免费看| 又粗又硬又长又爽又黄的视频| 中文资源天堂在线| 国产成人a∨麻豆精品| 在线看a的网站| 成年免费大片在线观看| 99久久精品热视频| 在线观看免费视频网站a站| 国产高清国产精品国产三级 | 丰满少妇做爰视频| 中文天堂在线官网| 亚洲精品456在线播放app| 国产真实伦视频高清在线观看| 欧美日韩亚洲高清精品| 日日撸夜夜添| 国产日韩欧美在线精品| 激情 狠狠 欧美| 亚洲经典国产精华液单| 麻豆成人午夜福利视频| 亚洲欧美日韩无卡精品| 涩涩av久久男人的天堂| 欧美少妇被猛烈插入视频| 黄色配什么色好看| 美女cb高潮喷水在线观看| 日产精品乱码卡一卡2卡三| 高清毛片免费看| 精品久久久久久久久av| 国产一区二区三区综合在线观看 | 亚洲欧美日韩东京热| 美女cb高潮喷水在线观看| 日日啪夜夜撸| 欧美极品一区二区三区四区| 在线观看三级黄色| 欧美日本视频| 97热精品久久久久久| 国产永久视频网站| 中文字幕制服av| 一级片'在线观看视频| 国产伦理片在线播放av一区| 国模一区二区三区四区视频| 91午夜精品亚洲一区二区三区| 亚洲精品国产av蜜桃| 国产欧美另类精品又又久久亚洲欧美| 中国美白少妇内射xxxbb| 国产精品久久久久久av不卡| 国产免费福利视频在线观看| 麻豆精品久久久久久蜜桃| 成人国产麻豆网| 国产成人精品一,二区| 久久ye,这里只有精品| 亚洲欧美日韩东京热| 久久国内精品自在自线图片| av播播在线观看一区| 国产亚洲av片在线观看秒播厂| 成人影院久久| 大陆偷拍与自拍| 免费在线观看成人毛片| 日本vs欧美在线观看视频 | 在线天堂最新版资源| 三级国产精品片| 精品久久久久久电影网| 另类亚洲欧美激情| 亚洲aⅴ乱码一区二区在线播放| 两个人的视频大全免费| 男人狂女人下面高潮的视频| 菩萨蛮人人尽说江南好唐韦庄| 99久久精品一区二区三区| 卡戴珊不雅视频在线播放|