Quick Search Adv. Search

J4 ›› 2011, Vol. 8 ›› Issue (4): 387-394.doi: 10.1016/S1672-6529(11)60044-9

• article • Previous Articles     Next Articles

Added Mass Effect and an Extended Unsteady Blade Element Model of Insect Hovering

Xingyao Yan1, Shanan Zhu2, Zhongdi Su1, Hongjun Zhang1   

  1. 1. College of Metrology Technology and Engineering, China Jiliang University, Hangzhou 310018, P. R. China
    2. College of Electrical Engineering, Zhejiang University, Hangzhou 310027, P. R. China
  • Online:2011-12-30
  • Contact: Xingyao Yan E-mail:zju_yan@163.com

Abstract:

During the insect flight, the force peak at the start of each stroke contributes a lot to the total aerodynamic force. Yet how this force is generated is still controversial. Two current explanations to this are wake capture and Added Mass Effect (AME) mechanisms. To study the AME, we present an extended unsteady blade element model which takes both the added mass of fluid and rotational effect of the wing into account. Simulation results show a high force peak at the start of each stroke and are quite similar to the measured forces on the physical wing model. We found that although the Added Mass Force (AMF) of the medium contributes a lot to this force peak, the wake capture effect further augments this force and may play a more important role in delayed mode. Furthermore, we also found that there might be an unknown mechanism which may augment the AME during acceleration period at the start of each stroke, and diminish the AME during deceleration at the end of each stroke.

Key words: added mass, wake capture, insect flight, simplified aerodynamic model