Numerical Investigation of an Offshore Oscillating Water Column

Frimpong Opoku¹, Michael Atkinson^1, and Mohammad Nasim Uddin¹

¹Mechanical Engineering, North Carolina A&T State University, Greensboro, USA

Cite this paper:
Frimpong Opoku, Michael Atkinson and Mohammad Nasim Uddin. Numerical Investigation of an Offshore Oscillating Water Column. American Journal of Mechanical Engineering. 2020; 8(3):88-105. doi: 10.12691/ajme-8-3-1

Abstract

In this study, a Numerical Wave Tank (NWT) was used to investigate the flowfield of an offshore Oscillating Water Column (OWC). An inviscid solution coupled to the Volume of Fluid method was carried out using ANSYS^TM Fluent to simulate six different offshore OWC configurations. The waterside chamber angle, θ₁, shoreside chamber angle, θ₂, and immersion extension depth d, were varied to evaluate their effect on pneumatic power and efficiency. It was determined that configuration parameters with θ₁ = 45^o, θ₂ = 90^o and d = 0 m produced the highest power with an efficiency of 23.1%; results showed that this case had a higher static pressure inside the duct which was the predominant reason for a higher pneumatic power. The cases with an additional extension into the water, d, was found to reduce the pneumatic power when compared to a similar case without an extension.

Keywords:
offshore oscillating water column numerical wave tank pneumatic power volume of fluid inviscid flow

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