The plate flutter problem is studied in detail in the assumption that Mach number is large, and for calculation of pressure acting on the plate piston theory can be used. This theory gives a simple expression for the pressure as a function of the plate deflection for M >> 1 [1?3]. For low Mach numbers, 1 < M < 1.7, piston theory is not valid, while exact potential flow theory gives a complex integral-differential expression for the pressure. Due to this, plate flutter problem at low supersonic speeds is studied insufficiently. Recently, with use of asymptotic method [4], another region of instability for plates of large lengths has been discovered. This region cannot be detected through piston theory [5], at that physical nature of instability differs from the known before. Later, existence of this instability, named 'single mode flutter', was confirmed experimentally [6]. In this paper, plate stability is studied numerically for arbitrary plate sizes. Stability boundaries of the first six modes are obtained. The effect of the problem parameters is studied.
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