Wells turbine blade profile optimization for better wave energy capture

Abstract

Summary Despite the fact that wave energy is available at no cost, it is always desired to harvest the maximum possible amount of this energy. The axial flow air turbines are commonly used with oscillating water column devices as a power take‐off system. The present work introduces a blade profile optimization technique that improves the air turbine performance while considering the complex 3D flow phenomena. This technique produces non‐standard blade profiles from the coordinates of the standard ones. It implements a multi‐objective optimization algorithm in order to define the optimum blade profile. The proposed optimization technique was successfully applied to a biplane Wells turbine in the present work. It produced an optimum blade profile that improves the turbine torque by up to 9.3%, reduces the turbine damping coefficient by 10%, and increases the turbine operating range by 5%. The optimized profile increases the annual average turbine power by up to 3.6% under typical sea conditions. Moreover, new blade profiles were produced from the wind turbine airfoil data and investigated for use with the biplane Wells turbine. The present work showed that two of these profiles could be used with low wave energy seas. Copyright © 2017 John Wiley & Sons, Ltd.

Optimalisasi Desain Turbin Wells pada Sistem Osilasi Kolom Air Pembangkit Listrik Tenaga Gelombang Laut Sebagai Upaya Meningkatkan Potensi Supply Energi Terbarukan pada Masyarakat Pesisir

“…Banyak cara dapat dilakukan untuk memodifikasi turbin Wells, terutama memodifikasi parameter desain yang tujuan utamanya adalah untuk meningkatkan efisiensi kerja turbin. Misalnya, modifikasi ketebalan dan lokasi sudu maksimum profil NACA standar (Shaaban, 2017), modifikasi bagian tengah dan ujung sweep sudu (Halder dkk., 2017), modifikasi pada sudu duadimensi dan kepadatan tip (Gratton, 2018), dan masih banyak lagi.…”

Passive Flow Control via Tip Grooving and Stall Fencing Mechanisms of a Marine Energy Harvesting Turbine

“…In addition, the use of a casing groove has demonstrated tremendous potential for stall delay by reducing the tip leakage losses 18 . Past researchers also applied varieties of optimization methods for better performance and delaying stall of the turbine [19][20][21] . The modified blade geometry considerably enhanced the turbine's performance.…”

Performance enhancement of Wells turbine: Combined radiused edge blade tip, static extended trailing edge, and variable thickness modifications

“…Researchers investigated various configuration such as bi-plane (Raghunathan and Tan, 1983), guide vanes (Gato, 1990), contra-rotating (Raghunathan and Beattie, 1996), blade sweep (Gato and Webster, 2001), variable chord (Govardhan and Dhanasekaran, 2002) and optimized airfoil profiles (Mohamed et al, 2011;Shaaban, 2017) to improve the Wells turbine performance. As discussed earlier, the TLF affects the performance of Wells turbine significantly.…”