Experimental study of beating motion of mosquito : Investigation on mechanics of the flapping

Abstract

Mosquito belongs to the Diptera and its beating is based upon indirect flight muscles. To investigate flapping of indirect flight, we cut their wing in a span direction by two methods; cutting right and left simultaneously and cutting right and left by turns. The results showed that flapping frequency increased with the decrease in wing span. It was suggested that mosquito was flapping by indirect flight muscles. We measured morphological parameter of mosquito wing. An enlarged scale model experiment was carried out using a very low speed wind tunnel under the condition that Reynolds number and Strouhal number were made equal to those of real mosquito. The flow around the wing model moving up and down was visualized using smoke. Unsteady vortices was generated on the upper surface of the model wing in the period of downstroke. We measured circulation by the vortices and calculated lift force on the assumption that the flow was quasi-steady.