اثر پروفيل مقطع پره يك ميكرو توربين بادي بر زمان راه‌اندازي آن

Effect of blade section profile on the starting time of a micro-wind turbine

در اين پژوهش به محاسبه زمان راه‌اندازي يك ميكرو توربين بادي پرداخته مي‌شود. به اين منظور از نظريه‌ي اندازه حركت المان پره استفاده شده و پس از صحت سنجي كد تهيه شده، پارامتر زمان راه‌اندازي محاسبه مي‌شود. سپس با توجه به محدوديت كاري رينولدز، چهار ايرفويل NACA4412، SD7062، SG6040 و SG6043 انتخاب و اثر بهره‌گيري از آن‌ها بررسي مي‌شود. نتايج نشان مي‌دهد استفاده از ايرفويل SG6043 نه تنها توان بيشتري را به همراه داشته بلكه زمان راه‌اندازي كمتري نيز دارد. نسبت بالاي برآ به پسآي ايرفويل SG6043 به همراه كم بودن مساحت سطح از عوامل اصلي برتري اين ايرفويل مي‌باشد.

The study investigates the effect of airfoil used in a horizontal axis wind turbine blade on its power coefficient and also the starting time. Although the effect of airfoil type used in wind turbine blades is known from the aerodynamics viewpoint and researchers have tried to use airfoils with high aerodynamic efficiency, the appropriate choose of an airfoil requires more investigation from the standpoint of starting. In this study, the output power and the starting time of a small horizontal axis wind turbine are calculated via blade element momentum theory. For that purpose, a numerical scheme is developed and validated by the experimental data. Thereafter, the four airfoils namely NACA4412, SD7062, SG6040 and SG6043 are selected and the effect of employing these profiles on the turbine performance is examined. The results reveal that the use of SG6043 airfoil not only leads to more output power but it also results in shorter starting time. The superiority of SG6043 over other airfoils are due to its higher lift to drag ratio and also its lower surface area.