اثر مجاورت به سطح آب بر خواص آيروديناميكي يك بالواره

EFFECT OF SURFACE PROXIMITY ON THE AERODYNAMIC PROPERTIES OF A SURFACE EFFECT CRAFTʹS AIRFOIL EFFECT CRAFT

In this paper, the variation of aerodynamic properties of an airfoil in ground or free surface proximity is investigated. The linear vortex panel method is extended to include the effect of the proximity of an airfoil to an arbitrary surface. Two methods are introduced for ground or free surface modeling and their limit of application are compared. Some simple experiments are also performed for experimental validation of the theoretical results. According to the results, effect of free surface deformation due to the motion of an airfoil in its proximity is negligible. Then one could consider the free surface as a solid one.The best section form for attaining favorable characteristicts near the surface is an airfoil with small camber and thickness, which is placed at small angle of attack. Wave surface form, i.e., wavelength and amplitude, could have a considerable effect on the aerodynamic properties. In summary, proximity of an airfoil to a wavy surface amplifies the surface effect. them as a tool to select magnetic field parameters. The current study has been confined to a magnetic field resulting from coils surronding a rectangular surface. In addition, an arbitary constraint might exist within the rectangle to be observed by the moving object. Besides the rectagular shapes, the methodology could well be extended to other shapes of magnetic fields.