Abstract

This research paper applies the blade element momentum theory on a horizontal axis wind turbine to study a 2-stage wind turbine with an independent rotating shaft, a type of small-scale wind turbine that has never been studied. The article also includes the Prandtl loss in the theory of the blade element momentum method to calculate the wind turbine so that the calculated power and efficiency are close to the actual efficiency instead of the consideration of ideal conditions. These theories have been around for a long time, but their applicability is still very high besides the use of modern computational tools such as computational fluid dynamics. Calculation results in the study are achieved by applying basic theories, then comparing with simulation results from Qblade software, a software that is commonly used in studies to calculate small and large-scale horizontal axis wind turbines and gives an error of less than 10%. This method is to ensure the objectivity and authenticity of the article. The proposed method in this study can be used to calculate various blade profiles of wind turbines. The paper aims to use the CL/CD ratio corresponding to a certain angle of attack as a specific case to optimize the calculation process, giving the problem can be automated.