This paper analyzes the nonlinear phenomenon of rotating stall via the methods of projection [Elementary Stability and Bifurcation Theory, G. Iooss and D. D. Joseph, Springer-Verlag, 1980] and Lyapunov [J.-H. Fu, Math. Control Signal Systems, 7, 255278, 1994]. A compressor model of Moore and Greitzer is adopted in which rotating stall dynamics are associated with Hopf bifurcations. Local stabil...

A plain journal bearing is spontaneously unstable above a critical speed and loses much of its load carrying capacity when subjected to a load rotating at about half the speed of the shaft. The almost axially symmetric flow in a compressor can break down at low flow into a rotating pattern of stall cells but only the special case of a single propagating stall cell gives rise to a mechanical cou...

An unsteady two-dimensional finite-volume solver was developed based on Van Leer’s flux splitting algorithm in conjunction with “Monotonic Upstream Scheme for Conservation Laws (MUSCL)” limiters to improve the order of accuracy and the two-layer Baldwin-Lomax turbulence model was also implemented. Two test cases were prepared to validate the solver. The computed results were compared with the e...

The following analysis is presented to serve as a preliminary design guide for micro turbine engine designers to consider the potential advantages of incorporating the Rampressor into their recuperated engine designs. It is shown that the increase in compressor efficiency and the shift in optimum pressure will increase the efficiency of the engine and lower the recuperator inlet temperature and...

As the analysis tool the well-known commercial software package (FINE/Design3D) is used. As the optimization software IOSO PM (parallel algorithm of IOSO) is used. The prospect presents the results of optimizing a three-stage axial compressor. The optimization goal was to improve the compressor efficiency at two flight conditions by optimizing geometry of the 5 compressor rows (62 design parame...