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Ocean wave energy represents a vast renewable energy resource which is mostly untapped. With the current focus on renewable energy, the ability to accurately test wave energy converter (WEC) designs is gaining importance both in research and in industry. The numerical testing of WEC geometry, in place of multiple scale experimental model testing sa...
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Citations
... Viscous fluid motion near the stagnation region of a solid body has motivated many researchers for more decades, where ''body" corresponds to either fix or moving surfaces [1][2][3] in a fluid. This multidisciplinary concept has frequent applications in, thrust bearings, thermal oil recovery, wave energy converters and air condensers [4,5]. ...
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... At the upstream end of domain, a constant velocity is specified for the current flow and the fluid is allowed to flow out at the downstream of the domain. The pressure gradient at the downstream end of the domain is assumed to be zero [26][27][28]: ...
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1 Abstract A numerical method is developed to capture the interaction of a solid object with two-phase flow with high density ratios. The full two-dimensional Navier-Stokes equations are solved on a regular structured grid to resolve the flow field. Level set and immersed boundary methods 1
Purpose
A numerical method is developed to capture the interaction of solid object with two-phase flow with high density ratios. The current computational tool would be the first step of accurate modeling of wave energy converters in which the immense energy of the ocean can be extracted at low cost.
Design/methodology/approach
The full two-dimensional Navier–Stokes equations are discretized on a regular structured grid, and the two-step projection method along with multi-processing (OpenMP) is used to efficiently solve the flow equations. The level set and the immersed boundary methods are used to capture the free surface of a fluid and a solid object, respectively. The full two-dimensional Navier–Stokes equations are solved on a regular structured grid to resolve the flow field. Level set and immersed boundary methods are used to capture the free surface of liquid and solid object, respectively. A proper contact angle between the solid object and the fluid is used to enhance the accuracy of the advection of the mass and momentum of the fluids in three-phase cells.
Findings
The computational tool is verified based on numerical and experimental data with two scenarios: a cylinder falling into a rectangular domain due to gravity and a dam breaking in the presence of a fixed obstacle. In the former validation simulation, the accuracy of the immersed boundary method is verified. However, the accuracy of the level set method while the computational tool can model the high-density ratio is confirmed in the dam-breaking simulation. The results obtained from the current method are in good agreement with experimental data and other numerical studies.
Practical/implications
The computational tool is capable of being parallelized to reduce the computational cost; therefore, an OpenMP is used to solve the flow equations. Its application is seen in the following: wind energy conversion, interaction of solid object such as wind turbine with water waves, etc.
Originality/value
A high efficient CFD approach method is introduced to capture the interaction of solid object with a two-phase flow where they have high-density ratio. The current method has the ability to efficiently be parallelized.