Unsteady Flow in a Single Stage Turbine

Abstract

This paper presents unsteady pressure and heat transfer measurements made on a high pressure turbine stage at DERA Pyestock, and compares them with numerical simulations made using the 2D unsteady code UNSFLO. The aim of the work was to evaluate the performance of the code, and to use the predictions to allow a fuller interpretation of the flow physics than could have been achieved from the measurements alone. The unsteady heat transfer and pressure fluctuations around the mid height section of the rotor blade have been examined in detail. Agreement between measured and predicted pressure fluctuations on the rotor was excellent. Interaction with the ngv potential field dominated the pressure surface, while the suction surface showed pressure waves moving forward over the blade, possibly as a result of shock/wake interaction.

Continuous Closed-Loop Transonic Linear Cascade for Aerothermal Performance Studies in Microturbomachinery

“…It is a crucial procedure for temporal stability and spatial periodicity [14]. However, the introduction of tailboards causes shockwave reflections from the solid boundaries and promotes undesirable pressure fluctuations [30]. In order to negate this effect, which is an artifact of the test conditions, the tailboards include 3 mm perforations at 60 deg incline to the flow (Fig.…”

Reducing Shock Interactions in Transonic Turbine via Three-Dimensional Aerodynamic Shaping

“…It is also apparent that many embodiments of the airfoil bow can increase resonant stresses. Fortunately for the airfoil designer, improvements in gas-turbine computational fluid dynamics (CFD) have allowed for ever more sophisticated flowfield predictions (e.g., Dunn [21] and Adamczyk [22]), and it is now possible to predict both the time-averaged and time-resolved pressure loadings on transonic airfoils with good accuracy within constraints consistent with appropriate code validation (e.g., Rao et al [23], Busby et al [24], Hilditch et al [25], and many others [26][27][28][29]). Design-optimization systems have previously been used in conjunction with steady-state flow solvers with beneficial effects on transonic turbine airfoils (e.g., Jennions and Adamczyk [30] and Clark et al [20]).…”

Time-resolved vane-rotor-vane interaction in a transonic one-and-a-half stage turbine

“…A small number of papers have described investigations into blade row interaction in high pressure turbines at engine representative conditions [9][10][11][12][13][14]. These papers have resulted in a good understanding of the interaction mechanism within the rst turbine stage.…”