This page has only limited features, please log in for full access.

Dr. Zhihua Ma
School of Computing, Mathematics and Digital Technology, The Manchester Metropolitan University, Manchester M1 5GD, England, UK

Basic Info


Research Keywords & Expertise

0 Parallel Computing
0 Wave breaking simulation
0 Multiphase flow modelling
0 Hydrodynamic impact
0 High-speed compressible flows

Fingerprints

Hydrodynamic impact

Honors and Awards

The user has no records in this section


Career Timeline

The user has no records in this section.


Short Biography

The user biography is not available.
Following
Followers
Co Authors
The list of users this user is following is empty.
Following: 0 users

Feed

Journal article
Published: 01 March 2020 in International Journal of Offshore and Polar Engineering
Reads 0
Downloads 0
ACS Style

Hao Chen; Zaibin Lin; Ling Qian; Zhihua Ma; Wei Bai. CFD Simulation of Wave Energy Converters in Focused Wave Groups Using Overset Mesh. International Journal of Offshore and Polar Engineering 2020, 30, 70 -77.

AMA Style

Hao Chen, Zaibin Lin, Ling Qian, Zhihua Ma, Wei Bai. CFD Simulation of Wave Energy Converters in Focused Wave Groups Using Overset Mesh. International Journal of Offshore and Polar Engineering. 2020; 30 (1):70-77.

Chicago/Turabian Style

Hao Chen; Zaibin Lin; Ling Qian; Zhihua Ma; Wei Bai. 2020. "CFD Simulation of Wave Energy Converters in Focused Wave Groups Using Overset Mesh." International Journal of Offshore and Polar Engineering 30, no. 1: 70-77.

Journal article
Published: 01 March 2020 in International Journal of Offshore and Polar Engineering
Reads 0
Downloads 0
ACS Style

Edward Ransley; Shiqiang Yan; Scott Brown; Martyn Hann; David Graham; Christian Windt; Pal Schmitt; Josh Davidson; John Ringwood; Pierre-Henri Musiedlak; Jinghua Wang; Junxian Wang; Qingwei Ma; Zhihua Xie; Ningbo Zhang; Xing Zheng; Giuseppe Giorgi; Hao Chen; Zaibin Lin; Ling Qian; Zhihua Ma; Wei Bai; Qiang Chen; Jun Zang; Haoyu Ding; Lin Cheng; Jinhai Zheng; Hanbin Gu; Xiwu Gong; Zhenghao Liu; Yuan Zhuang; Decheng Wan; Harry Bingham; Deborah Greaves. A Blind Comparative Study of Focused Wave Interactions with Floating Structures (CCP-WSI Blind Test Series 3). International Journal of Offshore and Polar Engineering 2020, 30, 1 -10.

AMA Style

Edward Ransley, Shiqiang Yan, Scott Brown, Martyn Hann, David Graham, Christian Windt, Pal Schmitt, Josh Davidson, John Ringwood, Pierre-Henri Musiedlak, Jinghua Wang, Junxian Wang, Qingwei Ma, Zhihua Xie, Ningbo Zhang, Xing Zheng, Giuseppe Giorgi, Hao Chen, Zaibin Lin, Ling Qian, Zhihua Ma, Wei Bai, Qiang Chen, Jun Zang, Haoyu Ding, Lin Cheng, Jinhai Zheng, Hanbin Gu, Xiwu Gong, Zhenghao Liu, Yuan Zhuang, Decheng Wan, Harry Bingham, Deborah Greaves. A Blind Comparative Study of Focused Wave Interactions with Floating Structures (CCP-WSI Blind Test Series 3). International Journal of Offshore and Polar Engineering. 2020; 30 (1):1-10.

Chicago/Turabian Style

Edward Ransley; Shiqiang Yan; Scott Brown; Martyn Hann; David Graham; Christian Windt; Pal Schmitt; Josh Davidson; John Ringwood; Pierre-Henri Musiedlak; Jinghua Wang; Junxian Wang; Qingwei Ma; Zhihua Xie; Ningbo Zhang; Xing Zheng; Giuseppe Giorgi; Hao Chen; Zaibin Lin; Ling Qian; Zhihua Ma; Wei Bai; Qiang Chen; Jun Zang; Haoyu Ding; Lin Cheng; Jinhai Zheng; Hanbin Gu; Xiwu Gong; Zhenghao Liu; Yuan Zhuang; Decheng Wan; Harry Bingham; Deborah Greaves. 2020. "A Blind Comparative Study of Focused Wave Interactions with Floating Structures (CCP-WSI Blind Test Series 3)." International Journal of Offshore and Polar Engineering 30, no. 1: 1-10.

Journal article
Published: 16 October 2019 in Ocean Engineering
Reads 0
Downloads 0

This paper presents a numerical study of oblique focused wave group generation and interaction with a fixed FPSO-shaped body, with thorough validations against available experimental data. The 3D numerical model is based on the open-source toolbox OpenFOAM®, where the oblique waves are generated using multiple virtual segmented wave paddles. The surface elevation and velocity profiles on each paddle are derived based on the snake principle, which mimics the behaviour of wave paddles in the physical wave tank. Numerical tests are firstly conducted for focused wave groups propagating obliquely in an empty wave tank using the proposed scheme. By analysis of the surface elevation, it is found that reasonably good quality of oblique wave fields can be generated in the central area of the wave basin. Furthermore, investigations are carried out on the effects of wave angles on the harmonic structures of the wave groups using the phase-inversion method. It is shown that while the wave angle has minor effects on the linear and second order harmonics, the third order harmonic is altered by the wave angles, albeit its magnitude is very small. Finally, to show the effectiveness of the numerical oblique wave generation method and the importance of the angle effects in the wave-structure interaction process, simulations are carried out for the oblique focused wave group interacting with a fixed FPSO-shaped body. The effects of the wave incidence angle are clearly shown from the comparison of the integrated wave forces between the cases with different wave propagating angles.

ACS Style

Hao Chen; Ling Qian; Wei Bai; Zhihua Ma; Zaibin Lin; Mi-An Xue. Oblique focused wave group generation and interaction with a fixed FPSO-shaped body: 3D CFD simulations and comparison with experiments. Ocean Engineering 2019, 192, 106524 .

AMA Style

Hao Chen, Ling Qian, Wei Bai, Zhihua Ma, Zaibin Lin, Mi-An Xue. Oblique focused wave group generation and interaction with a fixed FPSO-shaped body: 3D CFD simulations and comparison with experiments. Ocean Engineering. 2019; 192 ():106524.

Chicago/Turabian Style

Hao Chen; Ling Qian; Wei Bai; Zhihua Ma; Zaibin Lin; Mi-An Xue. 2019. "Oblique focused wave group generation and interaction with a fixed FPSO-shaped body: 3D CFD simulations and comparison with experiments." Ocean Engineering 192, no. : 106524.

Journal article
Published: 01 June 2019 in International Journal of Offshore and Polar Engineering
Reads 0
Downloads 0
ACS Style

Edward Ransley; Shiqiang Yan; Scott Andrew Brown; Tri Mai; David Graham; Qingwei Ma; Pierre-Henri Musiedlak; Allan Peter Engsig-Karup; Claes Eskilsson; Qian Li; Jinghua Wang; Zhihua Xie; Sriram Venkatachalam; Thorsten Stoesser; Yuan Zhuang; Qi Li; Decheng Wan; Gang Chen; Hao Chen; Ling Qian; Zhihua Ma; Clive Mingham; Derek Causon; Inno Gatin; Hrvoje Jasak; Vuko Vukcevic; Steven Downie; Pablo Higuera; Eugeny Buldakov; Dimitris Stagonas; Qiang Chen; Jun Zang; Deborah Greaves. A Blind Comparative Study of Focused Wave Interactions with a Fixed FPSO-like Structure (CCP-WSI Blind Test Series 1). International Journal of Offshore and Polar Engineering 2019, 29, 113 -127.

AMA Style

Edward Ransley, Shiqiang Yan, Scott Andrew Brown, Tri Mai, David Graham, Qingwei Ma, Pierre-Henri Musiedlak, Allan Peter Engsig-Karup, Claes Eskilsson, Qian Li, Jinghua Wang, Zhihua Xie, Sriram Venkatachalam, Thorsten Stoesser, Yuan Zhuang, Qi Li, Decheng Wan, Gang Chen, Hao Chen, Ling Qian, Zhihua Ma, Clive Mingham, Derek Causon, Inno Gatin, Hrvoje Jasak, Vuko Vukcevic, Steven Downie, Pablo Higuera, Eugeny Buldakov, Dimitris Stagonas, Qiang Chen, Jun Zang, Deborah Greaves. A Blind Comparative Study of Focused Wave Interactions with a Fixed FPSO-like Structure (CCP-WSI Blind Test Series 1). International Journal of Offshore and Polar Engineering. 2019; 29 (2):113-127.

Chicago/Turabian Style

Edward Ransley; Shiqiang Yan; Scott Andrew Brown; Tri Mai; David Graham; Qingwei Ma; Pierre-Henri Musiedlak; Allan Peter Engsig-Karup; Claes Eskilsson; Qian Li; Jinghua Wang; Zhihua Xie; Sriram Venkatachalam; Thorsten Stoesser; Yuan Zhuang; Qi Li; Decheng Wan; Gang Chen; Hao Chen; Ling Qian; Zhihua Ma; Clive Mingham; Derek Causon; Inno Gatin; Hrvoje Jasak; Vuko Vukcevic; Steven Downie; Pablo Higuera; Eugeny Buldakov; Dimitris Stagonas; Qiang Chen; Jun Zang; Deborah Greaves. 2019. "A Blind Comparative Study of Focused Wave Interactions with a Fixed FPSO-like Structure (CCP-WSI Blind Test Series 1)." International Journal of Offshore and Polar Engineering 29, no. 2: 113-127.

Journal article
Published: 23 February 2019 in Ocean Engineering
Reads 0
Downloads 0

This paper presents a numerical wave tank based on the overset mesh approach. Overset mesh is favourable to the moving mesh method owing to its ability to represent complex geometries whilst maintaining a good quality mesh, especially for large amplitude body motions. The numerical wave tank is developed by integrating a generic overset mesh functionality with an efficient wave generation library in OpenFOAM®. A series of benchmark test cases, including 2D regular waves interacting with a floating cylinder and box-shaped body with superstructures, 2D water entry of a rigid wedge and a ship hull section as well as the heave decay of a point absorber wave energy converter and the lifeboat motion in regular waves, are carried out to evaluate the capabilities of the developed numerical wave tank. The computed solutions agree well with the experimental data and other reference results reported in the literature, which demonstrates the capability of the numerical wave tank for modelling flow around structures with complex geometries under various wave conditions. The parallel efficiency of the solver, effects of the overlapping area on the solution accuracy and comparisons with the results from a dynamic mesh are also discussed.

ACS Style

Hao Chen; Ling Qian; Zhihua Ma; Wei Bai; Ye Li; Derek Causon; Clive Mingham. Application of an overset mesh based numerical wave tank for modelling realistic free-surface hydrodynamic problems. Ocean Engineering 2019, 176, 97 -117.

AMA Style

Hao Chen, Ling Qian, Zhihua Ma, Wei Bai, Ye Li, Derek Causon, Clive Mingham. Application of an overset mesh based numerical wave tank for modelling realistic free-surface hydrodynamic problems. Ocean Engineering. 2019; 176 ():97-117.

Chicago/Turabian Style

Hao Chen; Ling Qian; Zhihua Ma; Wei Bai; Ye Li; Derek Causon; Clive Mingham. 2019. "Application of an overset mesh based numerical wave tank for modelling realistic free-surface hydrodynamic problems." Ocean Engineering 176, no. : 97-117.

Journal article
Published: 12 September 2018 in Journal of Fluids and Structures
Reads 0
Downloads 0

We introduce a fluid–structure interaction (FSI) framework for the resolution of two-phase fluid flow problems and isothermal non-linear elastic bodies. The discretisation of both the fluid and solid governing equations relies exclusively on the finite volume method. A strong coupling partitioned approach is implemented to ensure the two-way coupling of information between the fluid and solid regions defined in the simulation. Moreover, this FSI framework is integrated on top of a multi-region coupling procedure developed in companion papers [Martínez-Ferrer et al. (2016, 2018)], which has been successfully applied in numerical wave tanks (NWTs), and shown to work transparently with standard domain decomposition techniques used in parallel simulations. Therefore, this retained approach results in a high performance computing strategy to carry out accurate and efficient FSI simulations of wave impacts against structures characteristic of ocean and coastal engineering problems. We conduct a series of test cases to verify the implementation of this FSI framework and its parallel performance for an increasing number of CPU cores. These benchmarks include the dynamic and static responses of cantilever and clamped beams under various loads, a lid-driven flow in an elastic cavity, the water entry of an elastic wedge and, finally, a water dam impact on an elastic plate. The results obtained in this work agree well with analytical solutions, laboratory measurements as well as other numerical simulations reported in the literature.

ACS Style

Pedro J. Martínez-Ferrer; Ling Qian; Zhihua Ma; Derek M. Causon; Clive G. Mingham. An efficient finite-volume method to study the interaction of two-phase fluid flows with elastic structures. Journal of Fluids and Structures 2018, 83, 54 -71.

AMA Style

Pedro J. Martínez-Ferrer, Ling Qian, Zhihua Ma, Derek M. Causon, Clive G. Mingham. An efficient finite-volume method to study the interaction of two-phase fluid flows with elastic structures. Journal of Fluids and Structures. 2018; 83 ():54-71.

Chicago/Turabian Style

Pedro J. Martínez-Ferrer; Ling Qian; Zhihua Ma; Derek M. Causon; Clive G. Mingham. 2018. "An efficient finite-volume method to study the interaction of two-phase fluid flows with elastic structures." Journal of Fluids and Structures 83, no. : 54-71.

Journal article
Published: 22 June 2018 in Ocean Engineering
Reads 0
Downloads 0

An immersed boundary method is applied to simulate the green water over a fixed deck by combining a level set method for the free water surface capturing. An efficient Navier-Stokes equation solver of second-order accuracy adopting the fractional step method at a staggered Cartesian grid system is used to solve the incompressible fluid motion. The numerical model is validated by comparing extensively the wave elevation and pressure with the experimental data for two types of fixed decks, which suggests that the developed immersed boundary method coupled with the level set method is very promising to predict green water problems due to its accuracy and efficiency. Furthermore, the cross-sectional velocity distribution over the deck, which is an important parameter in the industrial application, is computed and compared to the analytical Ritter's solution. It is found that Ritter's solution is much more conservative than the numerical simulations, which confirms the safe application of the simplified analytical solution in the current design practise. Volume of green water over the deck that affects the stability of deck is also tracked. The numerical results reveal that the amount of green water over both the two types of fixed decks shows a linear relationship with the relative wave height. This important finding may be very helpful for the prediction of deck elevation under a certain wave condition to reduce the occurrence of green water event.

ACS Style

Bin Yan; Wei Bai; Ling Qian; Zhihua Ma. Study on hydro-kinematic characteristics of green water over different fixed decks using immersed boundary method. Ocean Engineering 2018, 164, 74 -86.

AMA Style

Bin Yan, Wei Bai, Ling Qian, Zhihua Ma. Study on hydro-kinematic characteristics of green water over different fixed decks using immersed boundary method. Ocean Engineering. 2018; 164 ():74-86.

Chicago/Turabian Style

Bin Yan; Wei Bai; Ling Qian; Zhihua Ma. 2018. "Study on hydro-kinematic characteristics of green water over different fixed decks using immersed boundary method." Ocean Engineering 164, no. : 74-86.

Journal article
Published: 01 May 2018 in Journal of Computational Physics
Reads 0
Downloads 0
ACS Style

Jiale Zhang; Zhi-Hua Ma; Hong-Quan Chen; Cheng Cao. A GPU-accelerated implicit meshless method for compressible flows. Journal of Computational Physics 2018, 360, 39 -56.

AMA Style

Jiale Zhang, Zhi-Hua Ma, Hong-Quan Chen, Cheng Cao. A GPU-accelerated implicit meshless method for compressible flows. Journal of Computational Physics. 2018; 360 ():39-56.

Chicago/Turabian Style

Jiale Zhang; Zhi-Hua Ma; Hong-Quan Chen; Cheng Cao. 2018. "A GPU-accelerated implicit meshless method for compressible flows." Journal of Computational Physics 360, no. : 39-56.

Journal article
Published: 01 March 2018 in Ocean Engineering
Reads 0
Downloads 0

We introduce a dynamic-boundary numerical wave generation procedure developed for wave structure interaction (WSI) simulations typical of ocean and coastal engineering problems. This implementation relies on a dynamic mesh which deforms in order to replicate the motion of the wave-maker, and it is integrated in wsiFoam: a multi-region coupling strategy applied to two-phase Navier-Stokes solvers developed in our previous work [Martínez Ferrer et al. A multi-region coupling scheme for compressible and incompressible flow solvers for two-phase flow in a numerical wave tank. Computer & Fluids 125 (2016) 116–129]. The combination of the dynamic-boundary method with a multi-region mesh counteracts the increase in computational cost, which is intrinsic to simulations featuring dynamic domains. This approach results in a high performance computing wave generation strategy that can be utilised in a numerical wave tank to carry out accurate and efficient simulations of wave generation, propagation and interaction with fixed structures and floating bodies. We conduct a series of benchmarks to verify the implementation of this wave generation method and the capabilities of the solver wsiFoam to deal with wave structure interaction problems. These benchmarks include regular and focused waves, wave interaction with a floating body and the modelling of a wave energy converter, using different wave-maker geometries: piston, flap and plunger. The results gathered in this work agree well with experimental data measured in the laboratory and other numerical simulations.

ACS Style

Pedro J. Martínez-Ferrer; Ling Qian; Zhihua Ma; Derek M. Causon; Clive G. Mingham. Improved numerical wave generation for modelling ocean and coastal engineering problems. Ocean Engineering 2018, 152, 257 -272.

AMA Style

Pedro J. Martínez-Ferrer, Ling Qian, Zhihua Ma, Derek M. Causon, Clive G. Mingham. Improved numerical wave generation for modelling ocean and coastal engineering problems. Ocean Engineering. 2018; 152 ():257-272.

Chicago/Turabian Style

Pedro J. Martínez-Ferrer; Ling Qian; Zhihua Ma; Derek M. Causon; Clive G. Mingham. 2018. "Improved numerical wave generation for modelling ocean and coastal engineering problems." Ocean Engineering 152, no. : 257-272.

Journal article
Published: 01 March 2018 in International Journal of Offshore and Polar Engineering
Reads 0
Downloads 0
ACS Style

Pedro J Martínez-Ferrer; Ling Qian; Derek M Causon; Clive G Mingham; Zhihua Ma. Numerical Simulation of Wave Slamming on a Flap-Type Oscillating Wave Energy Device. International Journal of Offshore and Polar Engineering 2018, 28, 65 -71.

AMA Style

Pedro J Martínez-Ferrer, Ling Qian, Derek M Causon, Clive G Mingham, Zhihua Ma. Numerical Simulation of Wave Slamming on a Flap-Type Oscillating Wave Energy Device. International Journal of Offshore and Polar Engineering. 2018; 28 (1):65-71.

Chicago/Turabian Style

Pedro J Martínez-Ferrer; Ling Qian; Derek M Causon; Clive G Mingham; Zhihua Ma. 2018. "Numerical Simulation of Wave Slamming on a Flap-Type Oscillating Wave Energy Device." International Journal of Offshore and Polar Engineering 28, no. 1: 65-71.

Journal article
Published: 31 January 2018 in Computers & Fluids
Reads 0
Downloads 0

This paper extends a recently proposed multi-region based numerical wave tank (Martínez-Ferrer et al. [1]) to solve water entry problems in naval engineering. The original static linking strategy is developed to enable the dynamic coupling of several moving regions. This permits the method to deal with large-amplitude motions for structures slamming into water waves. A background grid and one or more component meshes are firstly generated to overlay the whole computational domain and the sub-domains surrounding the structures, respectively. During computation, the background mesh is fixed while the small grids move freely or as prescribed without deformation and regeneration. This effectively circumvents the large and often excessive error-prone dynamic deformation of a single-block mesh as well as the complex and time-consuming mesh regeneration. Test cases of dam breaking with and without obstacles are first conducted to verify the developed code by comparing the numerical solution against experimental data. Then the new code is used to solve prescribed and free-fall water entry problems. The obtained results agree well with experimental measurements and other computational results reported in the literature.

ACS Style

Z.H. Ma; Ling Qian; Pedro J. Martínez-Ferrer; D.M. Causon; C.G. Mingham; W. Bai. An overset mesh based multiphase flow solver for water entry problems. Computers & Fluids 2018, 172, 689 -705.

AMA Style

Z.H. Ma, Ling Qian, Pedro J. Martínez-Ferrer, D.M. Causon, C.G. Mingham, W. Bai. An overset mesh based multiphase flow solver for water entry problems. Computers & Fluids. 2018; 172 ():689-705.

Chicago/Turabian Style

Z.H. Ma; Ling Qian; Pedro J. Martínez-Ferrer; D.M. Causon; C.G. Mingham; W. Bai. 2018. "An overset mesh based multiphase flow solver for water entry problems." Computers & Fluids 172, no. : 689-705.

Journal article
Published: 09 October 2017 in Ocean Engineering
Reads 0
Downloads 0

This paper presents a numerical study of the gap resonance between two side-by-side barges by using a multiphase Navier-Stokes equations model. In order to verify the multiphase flow model, it is firstly applied to simulate a two-dimensional gap resonance problem for two fixed boxes under various wave conditions. A comparison of the free surface elevations obtained on successively refined grids confirms the mesh convergence of numerical solutions. The calculated wave elevation response amplitude operators (RAOs) in the gap compare well with the experimental measurements. The multiphase flow model is further extended to calculate a three-dimensional gap resonance problem for two adjacent rectangular barges. The computed free surface RAOs in the gap also agree well with the experimental results. A close examination of the flow velocity and vorticity in the gap region at the piston resonant mode reveals that large amount of vortices are generated by the sharp corners of the two barges and shed downwards, which provide an effective mechanism to dissipate the flow kinematic energy and to reduce the wave elevation in the gap. On the contrary, rounded corners are not able to induce the same level amount of vortices to dampen the gap resonance. The effects of incident wave steepness on the viscous damping associated with the twin-barge system are highlighted.

ACS Style

Xingya Feng; W. Bai; X.B. Chen; Ling Qian; Zhihua Ma. Numerical investigation of viscous effects on the gap resonance between side-by-side barges. Ocean Engineering 2017, 145, 44 -58.

AMA Style

Xingya Feng, W. Bai, X.B. Chen, Ling Qian, Zhihua Ma. Numerical investigation of viscous effects on the gap resonance between side-by-side barges. Ocean Engineering. 2017; 145 ():44-58.

Chicago/Turabian Style

Xingya Feng; W. Bai; X.B. Chen; Ling Qian; Zhihua Ma. 2017. "Numerical investigation of viscous effects on the gap resonance between side-by-side barges." Ocean Engineering 145, no. : 44-58.

Journal article
Published: 16 July 2016 in Ocean Engineering
Reads 0
Downloads 0

This paper presents a numerical investigation of a plunging wave impact event in a low-filling depressurised sloshing tank using a compressible multiphase flow model implemented in open-source CFD software. The main focus of this study is on the hydrodynamic loadings that impinge on the vertical wall of the tank. The detailed numerical solutions compare well with experimental results and confirm that an air trapped plunging wave impact causes the vertical wall to experience pulsating pressure loadings in which alternate positive and negative gauge pressures occur in sequence following the first applied pressure peak. The strongest pulsations of the pressure are found to be near the air pocket trapped by the water mass. The instantaneous pressure distribution along the vertical wall is nearly uniform in the area contained by the air pocket. The phases of pulsating pressures on the wall are in synchronisation with the expansion and contraction of the trapped air pocket. The pocket undergoes changes in shape, moves upwards with the water mass and eventually breaks up into small parts. A careful integration of the wall pressure reveals that the vertical structure as a whole experiences pulsating horizontal impact forces. It is found that the average period of pulsation cycles predicted in the present study is around 5–6 ms, and the loading pulsations are quickly damped out in 0.1–0.2s. Further exploratory investigation of the fluid thermodynamics reveals that the temperature inside the trapped air pocket rises quickly for about 2 ms synchronised with the pocket's first contraction, then the generated heat is rapidly transferred away in around 3 ms.

ACS Style

Z.H. Ma; D.M. Causon; Ling Qian; C.G. Mingham; Pedro J. Martínez-Ferrer. Numerical investigation of air enclosed wave impacts in a depressurised tank. Ocean Engineering 2016, 123, 15 -27.

AMA Style

Z.H. Ma, D.M. Causon, Ling Qian, C.G. Mingham, Pedro J. Martínez-Ferrer. Numerical investigation of air enclosed wave impacts in a depressurised tank. Ocean Engineering. 2016; 123 ():15-27.

Chicago/Turabian Style

Z.H. Ma; D.M. Causon; Ling Qian; C.G. Mingham; Pedro J. Martínez-Ferrer. 2016. "Numerical investigation of air enclosed wave impacts in a depressurised tank." Ocean Engineering 123, no. : 15-27.

Journal article
Published: 25 January 2016 in Physics of Fluids
Reads 0
Downloads 0

This paper presents an experimental and numerical investigation of the entry of a rigid square flat plate into pure and aerated water. Attention is focused on the measurement and calculation of the slamming loads on the plate. The experimental study was carried out in the ocean basin at Plymouth University’s COAST laboratory. The present numerical approach extends a two-dimensional hydro-code to compute three-dimensional hydrodynamic impact problems. The impact loads on the structure computed by the numerical model compare well with laboratory measurements. It is revealed that the impact loading consists of distinctive features including (1) shock loading with a high pressure peak, (2) fluid expansion loading associated with very low sub-atmospheric pressure close to the saturated vapour pressure, and (3) less severe secondary reloading with super-atmospheric pressure. It is also disclosed that aeration introduced into water can effectively reduce local pressures and total forces on the flat plate. The peak impact loading on the plate can be reduced by half or even more with 1.6% aeration in water. At the same time, the lifespan of shock loading is prolonged by aeration, and the variation of impulse is less sensitive to the change of aeration than the peak loading.

ACS Style

Z. H. Ma; D. M. Causon; L. Qian; C. G. Mingham; T. Mai; Deborah Greaves; Alison Raby. Pure and aerated water entry of a flat plate. Physics of Fluids 2016, 28, 016104 .

AMA Style

Z. H. Ma, D. M. Causon, L. Qian, C. G. Mingham, T. Mai, Deborah Greaves, Alison Raby. Pure and aerated water entry of a flat plate. Physics of Fluids. 2016; 28 (1):016104.

Chicago/Turabian Style

Z. H. Ma; D. M. Causon; L. Qian; C. G. Mingham; T. Mai; Deborah Greaves; Alison Raby. 2016. "Pure and aerated water entry of a flat plate." Physics of Fluids 28, no. 1: 016104.

Journal article
Published: 02 December 2015 in Computers & Fluids
Reads 0
Downloads 0

We present a multi-region coupling procedure based on the finite-volume method and apply it to two-phase hydrodynamic free surface flow problems. The method combines the features of one incompressible and one compressible two-phase flow solvers to obtain a coupled system which is generally superior to either solver alone. The coupling strategy is based on a partitioned approach in which different solvers, pre-defined in different regions of the computational domain, exchange information through interfaces, i.e. areas separating these regions. The interfaces act as boundary conditions passing the information from one region to the other mimicking the finite-volume cell-to-face interpolation procedures. This results in high performance computing coupled simulations whose functionality can be further extended in order to build a generic numerical wave tank accounting for incompressible flow regions as well as compressibility and aeration effects. We select a series of preliminary benchmarks to verify this coupling procedure which includes the simulation of a hydrodynamic dam break, the propagation and reflection of regular waves, the convection of an inviscid vortex, pseudocavitation, a water column free drop in a closed tank and a plunging wave impact at a vertical wall. The obtained results agree well with exact solutions, laboratory experiments and other numerical data.

ACS Style

P.J. Martínez Ferrer; D.M. Causon; Ling Qian; C.G. Mingham; Zhihua Ma. A multi-region coupling scheme for compressible and incompressible flow solvers for two-phase flow in a numerical wave tank. Computers & Fluids 2015, 125, 116 -129.

AMA Style

P.J. Martínez Ferrer, D.M. Causon, Ling Qian, C.G. Mingham, Zhihua Ma. A multi-region coupling scheme for compressible and incompressible flow solvers for two-phase flow in a numerical wave tank. Computers & Fluids. 2015; 125 ():116-129.

Chicago/Turabian Style

P.J. Martínez Ferrer; D.M. Causon; Ling Qian; C.G. Mingham; Zhihua Ma. 2015. "A multi-region coupling scheme for compressible and incompressible flow solvers for two-phase flow in a numerical wave tank." Computers & Fluids 125, no. : 116-129.

English abstract
Published: 01 September 2015 in Zhongguo Dang Dai Er Ke Za Zhi
Reads 0
Downloads 0
ACS Style

Buli Bahati; Zhi-Hua Ma; Abulaiti Abudouhaer. [Time series analysis of Enterobacter cloacae nosocomial infections in children hospitalized in the pediatric intensive care unit]. Zhongguo Dang Dai Er Ke Za Zhi 2015, 17, 1 .

AMA Style

Buli Bahati, Zhi-Hua Ma, Abulaiti Abudouhaer. [Time series analysis of Enterobacter cloacae nosocomial infections in children hospitalized in the pediatric intensive care unit]. Zhongguo Dang Dai Er Ke Za Zhi. 2015; 17 (9):1.

Chicago/Turabian Style

Buli Bahati; Zhi-Hua Ma; Abulaiti Abudouhaer. 2015. "[Time series analysis of Enterobacter cloacae nosocomial infections in children hospitalized in the pediatric intensive care unit]." Zhongguo Dang Dai Er Ke Za Zhi 17, no. 9: 1.

Journal article
Published: 21 July 2015 in Computers & Fluids
Reads 0
Downloads 0

This paper presents a GPU based compressible multiphase hydrocode for modelling violent hydrodynamic impacts under harsh conditions such as slamming and underwater explosion. An effort is made to extend a one-dimensional five-equation reduced model (Kapila et al., 2001) to compute three-dimensional hydrodynamic impact problems on modern graphics hardware. In order to deal with free-surface problems such as water waves, gravitational terms, which are initially absent from the original model, are now considered and included in the governing equations. A third-order finite volume based MUSCL scheme is applied to discretise the integral form of the governing equations. The numerical flux across a mesh cell face is estimated by means of the HLLC approximate Riemann solver. The serial CPU program is firstly parallelised on multi-core CPUs with the OpenMP programming model and then further accelerated on many-core graphics processing units (GPUs) using the CUDA C programming language. To balance memory usage, computing efficiency and accuracy on multi- and many-core processors, a mixture of single and double precision floating-point operations is implemented. The most important data like conservative flow variables are handled with double-precision dynamic arrays, whilst all the other variables/arrays like fluxes, residual and source terms are treated in single precision. Several benchmark test cases including water-air shock tubes, one-dimensional liquid cavitation tube, dam break, 2D cylindrical underwater explosion near a planar rigid wall, 3D spherical explosion in a rigid cylindrical container and water entry of a 3D rigid flat plate have been calculated using the present approach. The obtained results agree well with experiments, exact solutions and other independent numerical computations. This demonstrates the capability of the present approach to deal with not only violent free-surface impact problems but also hull cavitation associated with underwater explosions. Performance analysis reveals that the running time cost of numerical simulations is dramatically reduced by use of GPUs with much less consumption of electrical energy than on the CPU.

ACS Style

Z.H. Ma; D.M. Causon; Ling Qian; H.B. Gu; C.G. Mingham; Pedro J. Martínez-Ferrer. A GPU based compressible multiphase hydrocode for modelling violent hydrodynamic impact problems. Computers & Fluids 2015, 120, 1 -23.

AMA Style

Z.H. Ma, D.M. Causon, Ling Qian, H.B. Gu, C.G. Mingham, Pedro J. Martínez-Ferrer. A GPU based compressible multiphase hydrocode for modelling violent hydrodynamic impact problems. Computers & Fluids. 2015; 120 ():1-23.

Chicago/Turabian Style

Z.H. Ma; D.M. Causon; Ling Qian; H.B. Gu; C.G. Mingham; Pedro J. Martínez-Ferrer. 2015. "A GPU based compressible multiphase hydrocode for modelling violent hydrodynamic impact problems." Computers & Fluids 120, no. : 1-23.

Journal article
Published: 07 April 2015 in Current Pharmaceutical Biotechnology
Reads 0
Downloads 0
ACS Style

Peipei Tu; Zhihua Ma; Haisong Wang; Baicheng Ma; Xiaodan Li; Huikun Duan; Pingzhe Jiang; Miao Li; Ri Wu; Jianhong Zhu; Minggang Li. Expression of CTB-10×rolGLP-1 in E.coli and Its Therapeutic Effect on Type 2 Diabetes. Current Pharmaceutical Biotechnology 2015, 16, 564 -572.

AMA Style

Peipei Tu, Zhihua Ma, Haisong Wang, Baicheng Ma, Xiaodan Li, Huikun Duan, Pingzhe Jiang, Miao Li, Ri Wu, Jianhong Zhu, Minggang Li. Expression of CTB-10×rolGLP-1 in E.coli and Its Therapeutic Effect on Type 2 Diabetes. Current Pharmaceutical Biotechnology. 2015; 16 (6):564-572.

Chicago/Turabian Style

Peipei Tu; Zhihua Ma; Haisong Wang; Baicheng Ma; Xiaodan Li; Huikun Duan; Pingzhe Jiang; Miao Li; Ri Wu; Jianhong Zhu; Minggang Li. 2015. "Expression of CTB-10×rolGLP-1 in E.coli and Its Therapeutic Effect on Type 2 Diabetes." Current Pharmaceutical Biotechnology 16, no. 6: 564-572.

Journal article
Published: 01 January 2015
Reads 0
Downloads 0
ACS Style

Peipei Tu; Zhihua Ma; Haisong Wang; Baicheng Ma; Xiaodan Li; Huikun Duan; Pingzhe Jiang; Miao Li; Ri Wu; Jianhong Zhu; Minggang Li. Expression of CTB-10×rolGLP-1 in E. coli and its therapeutic effect on type 2 diabetes. 2015, 16, 1 .

AMA Style

Peipei Tu, Zhihua Ma, Haisong Wang, Baicheng Ma, Xiaodan Li, Huikun Duan, Pingzhe Jiang, Miao Li, Ri Wu, Jianhong Zhu, Minggang Li. Expression of CTB-10×rolGLP-1 in E. coli and its therapeutic effect on type 2 diabetes. . 2015; 16 (6):1.

Chicago/Turabian Style

Peipei Tu; Zhihua Ma; Haisong Wang; Baicheng Ma; Xiaodan Li; Huikun Duan; Pingzhe Jiang; Miao Li; Ri Wu; Jianhong Zhu; Minggang Li. 2015. "Expression of CTB-10×rolGLP-1 in E. coli and its therapeutic effect on type 2 diabetes." 16, no. 6: 1.

Conference paper
Published: 08 December 2014 in Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences
Reads 0
Downloads 0

This paper focuses on the numerical modelling of wave impact events under air entrapment and aeration effects. The underlying flow model treats the dispersed water wave as a compressible mixture of air and water with homogeneous material properties. The corresponding mathematical equations are based on a multiphase flow model which builds on the conservation laws of mass, momentum and energy as well as the gas-phase volume fraction advection equation. A high-order finite volume scheme based on monotone upstream-centred schemes for conservation law reconstruction is used to discretize the integral form of the governing equations. The numerical flux across a mesh cell face is estimated by means of the HLLC approximate Riemann solver. A third-order total variation diminishing Runge–Kutta scheme is adopted to obtain a time-accurate solution. The present model provides an effective way to deal with the compressibility of air and water–air mixtures. Several test cases have been calculated using the present approach, including a gravity-induced liquid piston, free drop of a water column in a closed tank, water–air shock tubes, slamming of a flat plate into still pure and aerated water and a plunging wave impact at a vertical wall. The obtained results agree well with experiments, exact solutions and other numerical computations. This demonstrates the potential of the current method to tackle more general wave–air–structure interaction problems.

ACS Style

Z. H. Ma; D. M. Causon; Ling Qian; C. G. Mingham; H. B. Gu; Pedro J. Martínez-Ferrer. A compressible multiphase flow model for violent aerated wave impact problems. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 2014, 470, 20140542 .

AMA Style

Z. H. Ma, D. M. Causon, Ling Qian, C. G. Mingham, H. B. Gu, Pedro J. Martínez-Ferrer. A compressible multiphase flow model for violent aerated wave impact problems. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 2014; 470 (2172):20140542.

Chicago/Turabian Style

Z. H. Ma; D. M. Causon; Ling Qian; C. G. Mingham; H. B. Gu; Pedro J. Martínez-Ferrer. 2014. "A compressible multiphase flow model for violent aerated wave impact problems." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 470, no. 2172: 20140542.