Fouling is an important performance degradation factor of axial flow compressor. Proper fouling sensitive parameter is crucial to more effectively monitor the fouling severity. Currently fouling level and cleaning necessity are judged by the decrease degree of thermodynamic performance parameter from macro point. But simulation research of NASA rotor 37 finds that tip clearance increase also ca...

Abstract―This paper illustrates the theory behind computational fluid dynamics (CFD) of flow though a gas turbine engine low pressure compressor. The goal of study is to develop a tool to perform shape optimization of low speed airfoils. Mathematical model and computational tool are developed using programming software. Analytical solution is developed to create airfoil geometry. The NACA 4 dig...

Introduction. This paper deals with some transonic flow problems for the supersonic axial flow compressor: these arise in connection with flutter analysis for fan blading. Very detailed solutions for unsteady plane transonic flows through a cascade of flat plates have been given by Goldstein Braun and Adamczyk (1977) and Nagashima and Whitehead (1977), see also Goldstein (1975), Kurosaka (1974)...

We show an application of the method of extremum seeking to the problem of maximizing the pressure rise in an axial flow compressor. First we apply extremum seeking to the Moore–Greitzer model and design a feedback scheme actuated through a bleed valve which simultaneously stabilizes rotating stall and surge and steers the system towards the equilibrium with maximal pressure. Then we implement ...

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...

Ever increasing demand of higher pressure ratio of aero-engine compressors has always been hindered by two distinct aerodynamic instabilities. The first known as surge is; large one dimensional periodic mass flow fluctuation through the compressor, which involves the entire pumping system including compressor, ducting, plenum and throttle. The second is the rotating stall which can be character...