Research Article  Open Access
RuChao Shi, RuiYuan Huang, GuangYong Wang, YouKai Wang, YongChi Li, "Numerical Simulation of Underwater Shock Wave Propagation in the Vicinity of Rigid Wall Based on Ghost Fluid Method", Shock and Vibration, vol. 2015, Article ID 467376, 16 pages, 2015. https://doi.org/10.1155/2015/467376
Numerical Simulation of Underwater Shock Wave Propagation in the Vicinity of Rigid Wall Based on Ghost Fluid Method
Abstract
This paper presents numerical simulation of underwater shock wave propagation nearby complex rigid wall. The Ghost Fluid Method (GFM) for the treatment of complex rigid wall is developed. The theoretical analysis on the GFMbased algorithm and relevant numerical tests demonstrate that the GFMbased algorithm is firstorder accurate as applied to complex rigid wall. A large number of challenging numerical tests show that the GFMbased algorithm is robust and quite simple in various practical problems. The numerical results on shock wave propagation in the vicinity of rigid wall are verified by comparing to exact solution and the results by bodyfittedgrid method.
1. Introduction
Numerical simulation of underwater shock wave propagation nearby rigid wall has been a hot area of research in computational physics [1ā3], computational biological fluid mechanics, [4] and computer graphics [5]. On the side of application for practical engineering problems, structure somewhile has to be assumed to be rigid wall to simplify computational models [6ā10] or to present comparisons for numerical results on deformable solid and elasticplastic solid [11ā14]. There are three kinds of methods by so far to simulate the shock wave propagation in the vicinity of rigid wall. One of them, which is also the most popular, is bodyfittedgrid method that need bodyfitted grids to be constructed in curvilinear coordinate system according to the shape of rigid wall [15ā19]. After the computational regions are discretized by bodyfitted grids, numerical methods such as finite difference method, finite volume method, and finite element method can be employed to solve the flow field. Among these three numerical methods, finite difference method may lead to geometrically induced errors [20] while finite volume method and finite element method have shown stability in numerical simulation; finite element method especially is competent to various complicated problems. Another kind of method is Cartesiangrid methods that require the rigid wall to be treated by special algorithm that may be very complicated and can be divided into firstorder method [21ā24] and secondorder method [25]. The application of this kind of method for underwater shock wave propagation can be found in [1] whereas there are very few applications of the Cartesiangrid methods since this kind of method is quite complicated in numerical implementation. The third kind is meshless methods (e.g., Smooth Particle Hydrodynamic method) that have widely applications for complex computational boundary but also have few applications for underwater shock wave propagation because of the large computational resources taken in numerical modelling and simulation.
In this work, we employ the idea of Ghost Fluid Method (GFM) in Cartesian grids to treat complex rigid wall to simulate underwater shock wave propagation. Actually, GFMs are not accurate for defining boundary condition, such as solidliquid interface, solidgas interface, liquidgas interface, and liquidliquid interface. However in recent years GFMs have shown wide range applications [26ā29] for shock wave propagation while interacting with material interface because of simplification and robustness. GFMs can be divided into original GFM (OGFM) and several improved versions. OGFM is developed by Fedkiw et al. [30] and the essence of nonoscillation has been verified. Nevertheless, OGFM is incapable in numerical simulation of multimedium that is very stiff at interface or where the density ratio is very large though it can be applied for low pressure gasliquid flow. Then a modified GFM (MGFM) is developed by Liu et al. [31], which is robust for gasliquid flow where the density ratio of the medium is very large. Next, real GFM (RGFM) [32] is developed to treat moving interface in some extreme situations. Subsequently some attempts in employing GFMs to treat liquidsolid interface and gassolid interface have been made. A few of simple applications of GFM for fluid/solid coupling are presented by Fedkiw [33] but GFM is still found to be inaccurate in some situations. To overcome this problem, an essentially MGFM for fluid/elastic solid coupling is proposed and developed by Liu et al. [34] by employing Navier equation to solve solid and constructing an approximate Riemann problem at the interface.
As GFM has the advantages of simplification, robustness, and flexibility, we apply the idea and essence of GFM for treatment of complex rigid wall. There are several problems that need to be solved. The dominant problem is how to define Riemann problem for waterrigid wall interface. The second problem is how to evaluate the flow states at ghost grid nodes. The last one is how to analyze the numerical accuracy of the GFMbased algorithm. The text below is arranged as follows. In Section 2, we briefly present the methods, governing equations and numerical schemes, which are employed to solve the flow field. In Section 3, the GFM for the treatment of waterrigid wall interface and analysis on conservation errors are presented in detail. In Section 4, the theoretical solution for underwater shock wave propagation in the vicinity of rigid wall is provided to further test the numerical error of GFMalgorithm developed. In Section 5, various challenging tests are carried out by GFMbased algorithm, bodyfittedgrids method, and theoretical analysis for further comparisons and discussions. In last section, brief conclusions are summarized and given.
2. Methods and Governing Equations
In this work, Euler equations are employed to solve flow field. While we apply GFM to rigid wall, level set method and related techniques are used to keep track of waterrigid wall interface and other material interfaces.
2.1. Euler Equations
The flow field is governed by Euler equations:where is density and , , and are velocities at , , and direction, respectively. is total energy which can be expressed asHere, is internal energy per unit mass. 2D Euler equations are obtained by setting . 1D Euler equations are obtained by setting and and can be given aswhere and . The total energy can be written asIn calculations, Euler equations are solved with fifthorder WENO spatial discretization [35] and secondorder RungeKutta (RK) time discretization.
2.2. Equations of State
For gas, we employ law which is expressed aswhere is pressure, is density, is internal energy per unit mass, and is the ratio of specific heats. For high pressure gas, we can also use JWL equation [36]:where is pressure, is density, is internal energy per unit mass, and , , , , and are constants.
For water, Tait equation [36] and isentropic onefluid model [37] are employed here and given aswhere is the saturated pressure of water, , , , , , , and the initial value of is set to be . For every iteration step, would be updated by if the result of is beyond . Generally, . To succinctly express the relationship between pressure and density , we rewrite the EOS of water that does not include gas phase asOne may find that pressure of water can be determined by density directly. For water, the internal energy per unit mass is also the function of density , which can be expressed as [36]Since the internal energy of water can be determined by the density directly, it is not necessary to solve corresponding energy conservation equation in calculations.
2.3. Level Set Method
We use level set equation [38] to keep track of material interface:where , , and are velocities in , , and directions, respectively. is the sign distance function of arbitrary point in the domain and can be written asFor 2D problems, in (10) is set to be . For 1D problems, both and are set to be . The velocity extension technique [39] is employed to improve the accuracy of results by level set method. In calculations, level set equation is discretized by fifthorder HJWENO [40] and secondorder RK method.
2.4. Constant Extrapolation Approach
One of the most important steps of GFM is extrapolation that can extrapolate flow states from real region to ghost region. The partial equations for extrapolations can be expressed as [30, 41]where is artificial time, is the flow states that need to be extrapolated, and is the vector normal material interface and will be given as . The sign āā is taken as ā+ā if the flow states need to be extended from to . If the flow states are extrapolated from to , we take ā.ā In calculations, (12) is simply solved by firstorder upwind MinMod scheme.
3. The GFM for Rigid Wall
GFMs include assuming that medium also exists outside the boundary of real medium, how to set ghost grid nodes for real medium and then how to update the flow states at these ghost grid nodes. In order to develop the GFM for rigid wall, we may first construct meshes on the entire domain neglecting whether or not the meshes are on the side of fluid (water). Then we extend the values at the grid nodes on the side of fluid (water) across fluidrigid wall interface to the other side where ghost fluid is assumed to exist and grid nodes are correspondingly set as ghost nodes. While we try to complete the two steps mentioned above, the interface between real fluid and ghost fluid needs to be defined and we choose level set function to describe this interface. The algorithm for updating status of ghost fluid nodes should retrain real fluid from escaping when real fluid interacts with the interface and should behave the essential features of rigid wall on the opposite side of real fluid.
3.1. GFMBased Algorithm
Supposing fluid is on left side of interface while rigid wall is on the right side of interface, we follow the ideology of [30, 31] and mathematically described the 1D GFM for treating fluidrigid wall interface aswhere the subscripts and , respectively, represent the status on the left and right side of interface and the sign āā refers to the ghost status at the related grid nodes. The density and velocity on the side of rigid wall can be considered asThe interfacial status at next time step will be predicted. Since GFM needs to behave the features of slip wall boundary for inviscid flow, we havewhere superscript āā indicates that the value of is predicted for next time step. will be extrapolated from interface to ghost region; hence we haveBy combining (14), (15), and (16), we haveSince density and pressure must satisfy continuous condition, we also extrapolate the values at the real grid nodes that are in the neighborhood of interface to ghost grid nodes, which can be expressed asThe illustration for GFM algorithm mentioned above is shown in Figure 1. For multidimensional problem, velocity resolutions are tangential velocity and normal velocity . and are obtained the same as and , and is treated as and :where will be determined byCorrespondingly, the schematic for multidimensional GFM algorithm is shown in Figure 2.
3.2. Analysis on Conservation Errors
Suppose the fluidrigid wall interface is located at where the rigid wall is on the right side of interface. Since the rigid wall is motionless, the location of interface will be treated as constant. The increase within fluid domain from the time to can be given asThe flux that flows out of fluid domain from the time to can be expressed asAs denotes three conservative variables, density, momentum, and energy, we haveBy computing double integral of 1D Euler equations (3) with the ranges and , we haveFurthermore,By combining (22), (23), and (25), we haveThe total conservation error is the sum of and and will be written asGFM for rigid wall has no ability to maintain conservation just like other applications of GFM. This is because the computational boundary of real medium is treated as mediummedium interface while this treatment is not absolute accurate. In numerical implementation, errors on mass conservation and shock location may occur. We only need to test the numerical accuracy of due to the linear relation between mass conservation error and shock location error. Let the computational domain be discretized by meshes. Locate the interface at one mesh where and is grid node so that interface is between (see Figure 3). Then will be given aswhere is the grid node at the boundary. For WENO scheme and RK method, the densities of all cells are not solved directly. Thus we use the density of two adjacent nodes to determine the density of cell, which can be expressed as where is density of cell and are the densities of grid nodes. The numerical test for conservation errors is presented in Case 1 of Section 5.
3.3. Numerical Implementation
The specific procedures for numerical simulation are summarized as follows.(1)Construct grid in entire domain and divide the grid nodes into real ones and ghost ones according to fluidrigid wall interface.(2)Define level set function (11) according to the fluidrigid wall interface.(3)Extrapolate the flow states (, , and ) at real gird nodes just near interface and interfacial flow states predicted into a narrow band in ghost region via (12).(4)Solve the values at grid nodes in entire domain for next time step.(5)Keep track of interface by level set method.(6)Update the values of grid nodes according to the numerical results in step .(7)Go to step for next time step. In step , the width of the band is set as to satisfy calculations based on fifthorder WENO spatial discretization and secondorder RK time discretization. In general, one can decide the width of band in accordance with the difference schemes for governing equations. The status of the ghost grid nodes outside the abovementioned band can be set as constants, for example, the initial parameters of fluid. For steps and , it is not necessary to define and solve the location by level set method for each time step because the rigid wall is motionless. However, if there are more than one kind of medium on the side of fluid, steps and should be repeated every time step.
4. Exact Solution for Underwater Shock Wave Propagation
Suppose there is an underwater shock wave moving right and its velocity relative to the fluid in front of shock is (). We build 1D shock wave fixed coordinates as shown in Figure 4. According to equation of continuity, equation of momentum, we havewhere the subscripts and indicate the status in front of shock and behind shock, respectively. The sign of tilde represents that the flow states are for moving coordinate system. Generally the flow states in front of shock such as pressure, density, and velocity () are already provided, and we can employ EOS for water (8) to close (29). Then the flow states behind shock in moving coordinates including velocity , density , and pressure can be solved. Eventually, one may obtain the velocity behind shock in global coordinates bywhere and are the respective velocities in front of shock and behind shock. The velocity of shock wave in global coordinates is .
Suppose the underwater shock wave mentioned above impacts on rigid wall and results in a reflection wave (see Figure 5). Similarly, we build reflection shock fixed coordinates. Due to conservation of mass and momentum, we havewhere the subscript indicates the flow states in front of reflection wave which is identical to the flow states behind the incident wave and the subscript denotes the flow states behind reflection wave, and the bars signify that status is in reflection wave fixed coordinates. Since pressure and density in front of reflection wave, and , can be determined by (29) and (30), we only need to use EOS of water and the relationship between shock wave coordinate system and global coordinate system to close (31). This relationship can be given aswhere is the velocity (in global coordinates) in front of reflection wave and will be determined by (29) and (30), is the velocity (in global coordinates) behind reflection wave and will be set as , and () is the velocity of reflection shock wave relative to the water in front of shock. By combination of (31), (32), and EOS of water, one can obtain variables , , , , and . The velocity of reflection wave in global coordinates is .
5. Results and Discussions
In this section, unless otherwise noted all calculations are done with employment of fifthorder WENO scheme to discretize spatial term of Euler equations, fifthorder HJWENO to discretize spatial term of level set equations, and secondorder RK method to discretize time term of both Euler equations and level set equations.
Case 1. The purpose of this case is to test the numerical accuracy of GFMbased algorithm. The computational domain is discretized with cells () and grid nodes. A rigid wall is situated at one cell when . The coordinate of rigid wall is set as where and an underwater shock wave is located at as shown in Figure 3. We will test numerical errors when to compare with numerical errors when . Since the location of rigid wall is , on the side of rigid wall, there are still six ghost nodal points that can be used to accomplish the numerical calculations when is equal to and fifthorder WENO and secondorder RK scheme are employed. The nondimensional initial parameters in front of incident shock are , , , and (means the velocity of shock wave is ). With the employment of theory in Section 4, the exact solution behind incident shock can be solved as , , and . And the exact solution behind reflection wave can be solved as , , , and (means the velocity of reflection wave is ). The computation is proceeded to . The conservation errors are presented in Table 1. The numerical results show that GFMbased algorithm is first order. The numerical results on density by GFM depicted in Figure 6 concur very well with the theoretical results.

Case 2. This is a 1D case for practical problem to test the performance of GFM for rigid wall. In this case, shock wave generated by underwater explosion hits rigid wall and then results in a reflection wave. The computational domain is with 100 meshes uniformly distributed. The interface between explosive and water is at . The rigid wall is located at . The regions of explosive and water are and , respectively. The boundary type at and is symmetric and outflow, respectively. The initial flow states for water are , , and . The initial status for explosive is , , and which are the parameters of TNT charge [36] and where JWL EOS needs to be employed. In addition, the grid nodes bordering explosivewater interface is updated by RGFM algorithm [32]. The computation is run to . Figures 7(a), 7(b), and 7(c), respectively, show pressure, density, and velocity profiles. The theoretical solution is also provided for comparison. There are few discrepancies between the numerical results and exact solution and the shock front are predicted accurately.
(a)
(b)
(c)
Case 3. This is also a 1D case for practical problem. In this case, the underwater shock wave is generated by underwater explosion whereas explosive gas is solved by law. The computational domain is . The waterrigid wall interface is located at . The radius of explosive is 0.5. The left boundary type of entire domain is symmetric. The initial flow states of explosive are , , and , and the initial flow states of water are , . The computation is run to . The numerical results by the GFM presented are depicted in Figure 8 and show that the density coincides very well with the theoretical results.
(a)
(b)
(c)
Case 4. This is a 2D case to test the performance of GFM for complex rigid wall in multidimensional practical problem. In this case, an underwater explosion of TNT charge occurs near complex rigid wall and then shock waves appear and propagate in the immediate vicinity of rigid wall. While GFMbased algorithm is employed to present numerical results, curvilinear coordinate system () is also constructed according to the shape of rigid wall to provide comparisons between numerical results by GFMbased algorithm and bodyfittedgrid method. The illustration of computational region is shown in Figure 9. The center of explosive is located at the origin . The initial flow states are , , , , , , , , and . The computational domain is . The shape of rigid wall satisfies . For calculations based on GFM, there are cells distributed uniformly to discretize computational domain with . For calculations based on bodyfittedgrid method, the computational domain on the side of fluid is discretized by cells where coordinates of nodal points satisfy and . Thus the cells in curvilinear coordinate system are smooth and the coordinates at every gird nodes are derivative. For each computational time step, the grid nodes bordering explosivewater interface are updated by RGFM algorithm. In Figures 10(a), 10(b), and 10(c), the differences between the results based on GFM and bodyfittedgrid method are shown. Obviously, both of these two methods can be used to capture the underwater shock save reflected from rigid wall. Few discernible discrepancies between the shape and locations of reflection waves, respectively, obtained by GFM and bodyfittedgrid method can be perceptible. In Figure 11, we provide pressure distribution at the bottom wall with different grid step. The interface obtained by GFM is implicit; thus, the pressure on waterrigid wall interface is not able to be solved directly. We output the pressure at the grid nodes just bordering the rigid wall. Since there is distance between these grid nodes and rigid wall, and reflection wave propagates with decreasing strength, the pressure distribution output by GFM is below the results by bodyfittedgrid method.
(a)
(b)
(c)
Case 5. This is a 3D case which is taken directly form [37]. The related experiment results on this case have been presented in [42]. A sphere PETN charge is located in the center of a container full of water. The diameter and height of the container are and , respectively. The diameter of explosive is . Since we cut the container in half, the computational domain is set to be and discretized by uniform cells. The initial status of water and explosive is , , , , , , , , , , and . For each computational time step, the grid nodes bordering explosivewater interface are updated by MGFM algorithm [31]. Figure 12 shows the processes for underwater shock wave propagation in rigid container. The pressure contours on meridian plane by using 2D axissymmetric Euler equation has been presented in [37]. For ease of comparison we also present the pressure contours and pressure cloud pictures on the meridian plane. Once the explosion starts, an underwater shock wave is generated and propagates to cylindrical wall with decreasing strength resulting in a reflection wave from the wall. The reflection wave hits the explosivewater interface and generates a rarefaction wave as shown in Figure 12(a). The rarefaction wave moves toward column wall and then makes a reflection wave again as shown in Figure 12(b). This new reflection wave is also very strong and creates cavitation flow in the vicinity of rigid wall as shown in Figure 12(c). Meanwhile the rarefaction wave toward basal plan is so strong that cavitation region is created in the immediate vicinity of gaswater interface as shown in Figure 12(d). We may note that numerical results shown in Figure 12 are consistent with numerical results by 2D axissymmetric Euler equation and experiments. In Figure 13, we compare the results presented, the results by 2D axissymmetric Euler equation and experimental results. It can be noticed that all the contour lines are almost uniformly distributed. We export the pressure history at the internal grid node to compare with pressure history at the boundary by 2D axissymmetric Euler equations. There are few discrepancies between the two profiles. Since elasticplastic solid is assumed to be rigid body in both the numerical models developed in this paper and the numerical method developed in [37], one may find that the third profile by experiments decreases more rapidly after peaking at about .
(a)
(b)
(c)
(d)
Case 6. This challenging case is used to test the performance of GFM on the treatment of quite complex rigid wall. In Figure 14, the explosive is located in the center of ellipsoidal vessel whose radii are respectively , and . Constructing Cartesian coordinate system along with the axis of vessel while setting the center of vessel is the origin , we can write the equation of ellipsoid as . The length of explosive is set to be . The angles of inclination between the axis of column and Cartesian coordinate system are , , and respectively. The computational domain is defined as with grid nodes uniformly distributed. The initial flow states are , , , , and . Once the explosion is initiated, a strong shock wave is generated and propagates outwards the wall of vessel with exponentially decreasing strength while high pressure bubble is expanding rapidly. As shown in Figure 15 shock wave hits rigid wall resulting in a strong reflection wave. Figure 16 shows that reflection wave hits the bubble and then generates rarefaction wave while expanding of bubble becomes slow because of the impact of shock wave. Figure 17 shows that the reflection waves from the rigid wall intersect and interact with each other resulting in another new strong reflection shock wave which propagates towards the wall at the end of long axis of vessel. Figure 18 shows that this new reflection wave reflects from the end of vessel and then results in third reflection wave that propagates toward the bubble (shown in Figure 19). This third reflection wave is so strong that cavitation flow (see Figure 20) occurs in large areas nearby rigid wall. One can notice that no contour distortion is found and all the contour lines are nearly regularly distributed. This also demonstrates the efficiency and robustness of GFM for rigid wall.
6. Conclusions
In this work, we propose and develop a GFMbased algorithm for the treatment of complex rigid wall and present numerical simulation of underwater shock wave propagation nearby rigid wall. GFM for complex rigid wall is tested and verified by comparing to exact solution and the results by bodyfittedgrid method. Numerical simulation on strong underwater shock wave is more challenging and more difficult than numerical simulation for normal shock wave so most of our tests focus on extreme situations where the pressure is quite high. GFM for complex rigid wall is verified to be firstorder accuracy on mass conservation and very simple and robust in various practical problems.
Conflict of Interests
The authors declare that there is no conflict of interests regarding the publication of this paper.
Acknowledgments
The research is mainly supported by Doctoral Fund of Henan Polytechnic University (Grant no. 60707/011) and supported in part by National Natural Science Foundation of China (Grant no. 11402266) and the Fund of the State Key Laboratory of Disaster Prevention & Mitigation of Explosion & Impact (PLA University of Science and Technology, Grant no. DPMEIKF201401).
References
 T. G. Liu, B. C. Khoo, K. S. Yeo, and C. Wang, āUnderwater shockfree surfacestructure interaction,ā International Journal for Numerical Methods in Engineering, vol. 58, no. 4, pp. 609ā630, 2003. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 S. Shin, āInternal wave computations using the ghost fluid method on unstructured grids,ā International Journal for Numerical Methods in Fluids, vol. 47, no. 3, pp. 233ā251, 2005. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 W. F. Xie, T. G. Liu, and B. C. Khoo, āApplication of a onefluid model for large scale homogeneous unsteady cavitation: the modified Schmidt model,ā Computers and Fluids, vol. 35, no. 10, pp. 1177ā1192, 2006. View at: Publisher Site  Google Scholar
 A. P. Bhalla, R. Bale, B. E. Griffith, and N. A. Patankar, āA unified mathematical framework and an adaptive numerical method for fluidstructure interaction and rigid, deforming, and elastic bodies,ā Journal of Computational Physics, vol. 250, pp. 446ā476, 2013. View at: Publisher Site  Google Scholar  MathSciNet
 R. Bridson, Fluid Simualtion for Compter Fluids, A K Peters, Natick, Mass, USA, 2007.
 M. R. Motley, Y. L. Young, and Z. Liu, āThreedimensional underwater shock response of composite marine structures,ā Journal of Applied Mechanics—Transactions ASME, vol. 78, no. 6, 2011. View at: Publisher Site  Google Scholar
 A. Schiffer and V. L. Tagarielli, āThe response of rigid plates to blast in deep water: fluidstructure interaction experiments,ā Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences, vol. 468, no. 2145, pp. 2807ā2828, 2012. View at: Publisher Site  Google Scholar
 R. Ghoshal and N. Mitra, āNoncontact nearfield underwater explosion induced shockwave loading of submerged rigid structures: nonlinear compressibility effects in fluid structure interaction,ā Journal of Applied Physics, vol. 112, no. 2, Article ID 024911, 2012. View at: Publisher Site  Google Scholar
 M. Riley, M. Smith, J. E. van Aanhold, and N. Alin, āLoading on a rigid target from close proximity underwater explosions,ā Shock and Vibration, vol. 19, no. 4, pp. 555ā571, 2012. View at: Publisher Site  Google Scholar
 M. Greco, G. Colicchio, and O. M. Faltinsen, āA domaindecomposition strategy for a compressible multiphase flow interacting with a structure,ā International Journal for Numerical Methods in Engineering, vol. 98, no. 11, pp. 840ā858, 2014. View at: Publisher Site  Google Scholar  MathSciNet
 Z. Zong, āDynamic plastic response of a submerged freefree beam to an underwater gas bubble,ā Acta Mechanica, vol. 161, no. 34, pp. 179ā194, 2003. View at: Google Scholar  Zentralblatt MATH
 S. Iakovlev, āInteraction between a submerged evacuated cylindrical shell and a shock wave—part I: diffractionradiation analysis,ā Journal of Fluids and Structures, vol. 24, no. 7, pp. 1077ā1097, 2008. View at: Publisher Site  Google Scholar
 S. Iakovlev, āInteraction between a submerged evacuated cylindrical shell and a shock wave—part II: numerical aspects of the solution,ā Journal of Fluids and Structures, vol. 24, no. 7, pp. 1098ā1119, 2008. View at: Publisher Site  Google Scholar
 Q. Li, M. Manolidis, and Y. L. Young, āAnalytical modeling of the underwater shock response of rigid and elastic plates near a solid boundary,ā Journal of Applied Mechanics, Transactions ASME, vol. 80, no. 2, Article ID 21017, 2013. View at: Publisher Site  Google Scholar
 S. Beji and K. Nadaoka, āFully dispersive nonlinear water wave model in curvilinear coordinates,ā Journal of Computational Physics, vol. 198, no. 2, pp. 645ā658, 2004. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 H. Zhang, L. Zhu, and Y. You, āA numerical model for wave propagation in curvilinear coordinates,ā Coastal Engineering, vol. 52, no. 6, pp. 513ā533, 2005. View at: Publisher Site  Google Scholar
 J. Huang, P. M. Carrica, and F. Stern, āCoupled ghost fluid/twophase level set method for curvilinear bodyfitted grids,ā International Journal for Numerical Methods in Fluids, vol. 55, no. 9, pp. 867ā897, 2007. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 A. Baghlani, N. Talebbeydokhti, and M. J. Abedini, āA shockcapturing model based on fluxvector splitting method in boundaryfitted curvilinear coordinates,ā Applied Mathematical Modelling, vol. 32, no. 3, pp. 249ā266, 2008. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 F.F. Tong, Y.M. Shen, J. Tang, and L. Cui, āWater wave simulation in curvilinear coordinates using a timedependent mild slope equation,ā Journal of Hydrodynamics, vol. 22, no. 6, pp. 796ā803, 2010. View at: Publisher Site  Google Scholar
 R. G. Hindman, āgeneralized coordinate forms of governing fluid equations and associated geometrically induced errors,ā AIAA Journal, vol. 20, no. 10, pp. 1359ā1367, 1982. View at: Google Scholar
 M. J. Berger and R. J. LeVeque, āA rotated difference scheme for cartesian grids in complex geometries,ā AIAA Paper CP911602, 1991. View at: Google Scholar
 J. J. Quirk, āAn alternative to unstructured grids for computing gas dynamic flows around arbitrarily complex twodimensional bodies,ā Computers and Fluids, vol. 23, no. 1, pp. 125ā145, 1994. View at: Publisher Site  Google Scholar
 R. B. Pember, J. B. Bell, P. Colella, W. Y. Curtchfield, and M. L. Welcome, āAn adaptive Cartesian grid method for unsteady compressible flow in irregular regions,ā Journal of Computational Physics, vol. 120, no. 2, pp. 278ā298, 1995. View at: Publisher Site  Google Scholar
 H. Forrer, āBoundary treatment for a cartesian grid method,ā ETH Research Report No. 9604, 1996. View at: Google Scholar
 H. Forrer and R. Jeltsch, āA higherorder boundary treatment for Cartesiangrid methods,ā Journal of Computational Physics, vol. 140, no. 2, pp. 259ā277, 1998. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 B. Zhang, H. Liu, F. Chen, and G. Wang, āNumerical simulation of flow fields induced by a supersonic projectile moving in tubes,ā Shock Waves, vol. 22, no. 5, pp. 417ā425, 2012. View at: Publisher Site  Google Scholar
 C.H. Chang, X. Deng, and T. G. Theofanous, āDirect numerical simulation of interfacial instabilities: a consistent, conservative, allspeed, sharpinterface method,ā Journal of Computational Physics, vol. 242, pp. 946ā990, 2013. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 Z. D. Wu, L. Sun, and Z. Zong, āComputational investigation of the mitigation of an underwater explosion,ā Acta Mechanica, vol. 224, no. 12, pp. 3159ā3175, 2013. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 A. Lopez Ortega, M. Lombardini, D. I. Pullin, and D. I. Meiron, āNumerical simulation of elasticplastic solid mechanics using an Eulerian stretch tensor approach and HLLD Riemann solver,ā Journal of Computational Physics, vol. 257, pp. 414ā441, 2014. View at: Publisher Site  Google Scholar  MathSciNet
 R. P. Fedkiw, T. Aslam, B. Merriman, and S. Osher, āA nonoscillatory Eulerian approach to interfaces in multimaterial flows (the ghost fluid method),ā Journal of Computational Physics, vol. 152, no. 2, pp. 457ā492, 1999. View at: Publisher Site  Google Scholar  MathSciNet
 T. G. Liu, B. C. Khoo, and K. S. Yeo, āGhost fluid method for strong shock impacting on material interface,ā Journal of Computational Physics, vol. 190, no. 2, pp. 651ā681, 2003. View at: Publisher Site  Google Scholar  Zentralblatt MATH
 C. W. Wang, T. G. Liu, and B. C. Khoo, āA real ghost fluid method for the simulation of multimedium compressible flow,ā SIAM Journal on Scientific Computing, vol. 28, no. 1, pp. 278ā302, 2006. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 R. P. Fedkiw, āCoupling an Eularian fluid calculation to a Lagrangian solid calculation with the ghost fluid method,ā Journal of Computational Physics, vol. 175, no. 1, pp. 200ā224, 2002. View at: Publisher Site  Google Scholar
 T. G. Liu, J. Y. Ho, B. C. Khoo, and A. W. Chowdhury, āNumerical simulation of fluidstructure interaction using modified ghost fluid method and Naviers equations,ā Journal of Scientific Computing, vol. 36, no. 1, pp. 45ā68, 2008. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 C.W. Shu, āEssentially nonoscillatory and weighted essentially nonoscillatory schemes for hyperbolic conservation laws,ā Brown University Report ICASE9765, 1997. View at: Google Scholar
 A. B. Wardlaw, āUnderwater explosion test cases,ā IHTR 2069, 1998. View at: Google Scholar
 T. G. Liu, B. C. Khoo, and W. F. Xie, āIsentropic onefluid modelling of unsteady cavitating flow,ā Journal of Computational Physics, vol. 201, no. 1, pp. 80ā108, 2004. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 S. Osher and J. A. Sethian, āFronts propagating with curvaturedependent speed: algorithms based on HamiltonJacobi formulations,ā Journal of Computational Physics, vol. 79, no. 1, pp. 12ā49, 1988. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 D. Adalsteinsson and J. A. Sethian, āThe fast construction of extension velocities in level set methods,ā Journal of Computational Physics, vol. 148, no. 1, pp. 2ā22, 1999. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 G.S. Jiang and D. Peng, āWeighted ENO schemes for HamiltonJacobi equations,ā SIAM Journal on Scientific Computing, vol. 21, no. 6, pp. 2126ā2143, 2000. View at: Publisher Site  Google Scholar  MathSciNet
 T. D. Aslam, āA partial differential equation approach to multidimensional extrapolation,ā Journal of Computational Physics, vol. 193, no. 1, pp. 349ā355, 2004. View at: Publisher Site  Google Scholar  Zentralblatt MATH  MathSciNet
 A. B. Wardlaw Jr. and J. A. Luton, āFluidstructure interaction mechanisms for closein explosions,ā Shock and Vibration, vol. 7, no. 5, pp. 265ā275, 2000. View at: Publisher Site  Google Scholar
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Copyright © 2015 RuChao Shi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.