TY - JOUR
T1 - Numerical analysis of effects of arms with different cross-sections on straight-bladed vertical axis wind turbine
AU - Hara, Yutaka
AU - Horita, Naoki
AU - Yoshida, Shigeo
AU - Akimoto, Hiromichi
AU - Sumi, Takahiro
N1 - Funding Information:
Funding: This research was supported by the International Platform for Dryland Research and Education (IPDRE), Tottori University, the Collaborative Research Program of Research Institute for Applied Mechanics, Kyushu University, and the Grant-in-Aid for Scientific Research (16H04599) from the Japan Society for the Promotion of Science.
Funding Information:
This research was supported by the International Platform for Dryland Research and Education (IPDRE), Tottori University, the Collaborative Research Program of Research Institute for Applied Mechanics, Kyushu University, and the Grant-in-Aid for Scientific Research (16H04599) from the Japan Society for the Promotion of Science.
PY - 2019
Y1 - 2019
N2 - Most vertical axis wind turbines (VAWTs) need arms connecting the blades with the rotational axis. The arms increase the power loss of VAWTs; however, the distribution between the pressure and friction influences and their degrees of influence have not yet been investigated in detail in past research. We applied computational fluid dynamics (CFD) targeting a small-sized straight-bladed VAWT to elucidate the effects of arms on turbine performance. In the analysis, three kinds of arms with different cross-sections (NACA 0018 airfoil, 18% rectangular, circular) with the same height were added to an armless rotor. The tangential forces and resistance torques caused by the added arms were recalculated by dividing the pressure and friction influences based on the surface pressure and friction distributions obtained by the CFD on an arm or a blade. The pressure-based tangential force of an arm, regardless of the cross-section, had a tendency to increase near the connection part between the arm and a blade. Though the value was small, the friction on the rectangular arm generated a driving force, whereas the friction on the other arms generated resistance forces. The pressure-based tangential force of a blade increased for a wide region around the connection part. The friction-based tangential force of a blade dropped around the connection part of every arm-equipped rotor. The arm resistance torque added to a VAWT by the existence of arms was larger than the added blade resistance torque in the cases of rectangular and circular arm rotors. Conversely, in the case of the airfoil arm rotor, the resistance torque added to blades became larger than that of arms.
AB - Most vertical axis wind turbines (VAWTs) need arms connecting the blades with the rotational axis. The arms increase the power loss of VAWTs; however, the distribution between the pressure and friction influences and their degrees of influence have not yet been investigated in detail in past research. We applied computational fluid dynamics (CFD) targeting a small-sized straight-bladed VAWT to elucidate the effects of arms on turbine performance. In the analysis, three kinds of arms with different cross-sections (NACA 0018 airfoil, 18% rectangular, circular) with the same height were added to an armless rotor. The tangential forces and resistance torques caused by the added arms were recalculated by dividing the pressure and friction influences based on the surface pressure and friction distributions obtained by the CFD on an arm or a blade. The pressure-based tangential force of an arm, regardless of the cross-section, had a tendency to increase near the connection part between the arm and a blade. Though the value was small, the friction on the rectangular arm generated a driving force, whereas the friction on the other arms generated resistance forces. The pressure-based tangential force of a blade increased for a wide region around the connection part. The friction-based tangential force of a blade dropped around the connection part of every arm-equipped rotor. The arm resistance torque added to a VAWT by the existence of arms was larger than the added blade resistance torque in the cases of rectangular and circular arm rotors. Conversely, in the case of the airfoil arm rotor, the resistance torque added to blades became larger than that of arms.
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U2 - 10.3390/en12112106
DO - 10.3390/en12112106
M3 - Article
AN - SCOPUS:85067231590
SN - 1996-1073
VL - 12
JO - Energies
JF - Energies
IS - 11
M1 - 2106
ER -
