Abstract
The objective of this study is to clarify the aerodynamic characteristics of the triangular shaped airfoil at very low Reynolds number corresponding to the Mars airplane flying in very low atmospheric density on Mars. Two-dimensional aerodynamic forces and pitching moments of the thin angular airfoils and the triangular airfoils with various thicknesses were studied through wind tunnel tests conducted in very low Reynolds number range of 3,000 - 20,000. Although the maximum lift coefficient and lift-to-drag ratio were large even for the triangular airfoil composed of a line pattern at the present Reynolds number, these aerodynamic components were affected in the airfoil thicknesses by changing the Reynolds number. The non-linear lift and pitching moment curves were characterized in low Reynolds number flows. It was found that the non-linearity of the aerodynamic curves was caused by the existence of the leading-edge separation bubble by measuring the pressure distributions of the airfoil at various Reynolds numbers.
