An Aspect of Aerofoil Lift and Pressure Distribution: Lecture Given to the Glasgow University Maclaurin Society on 17th November, 1982. G.U. Aero Report 8207

No abstract available

Comments on the Prediction of Dynamic Stall. G.U. Aero Report 8501

Summary: This report contains a brief discussion on the categories and capabilities of current methods of predicting dynamic stall. The categories considered are similar to those of previous surveys, whilst the quality and capabilities of each model considered, are assessed on the basis of the currently accepted salient features of the stall and other influential factors. The subjective assessments of the model details are concisely presented in tabular form which covers the major portion of the work. The table is intended as a quick reference guide to the models. Finally, the report concludes with a speculative discussion on future prospects

The Aerodynamic Characteristics of a GU25-5(11)8 Aerofoil for Low Reynolds' Numbers. G.U. Aero Report 8410

The paper presents the results of wind tunnel tests of a GU25-5(11)8 aerofoil section over the Reynolds number range, 50,000 to 610,000. For the particular test conditions, the aerofoil exhibits severe degradation of performance below Re = 300,000; a phenomenon which is known to be quite general. This particular aerofoil section has been used for the canards of microlights where low Reynolds numbers are not uncommon

The Prediction of Turbulent Boundary Layers. G.U. Aero Report 7702

Summary: In the past there has been some argument about how the problem of predicting turbulent boundary layers could best be handled. The present paper attempts to alleviate some of the disagreement and separately treats the model and the solution procedure. It is shown that the choice of dependent variable for the closure hypothesis is of minor importance when compared to the final form of the model. Consideration is also given to the way in which simple models, such as the constant eddy-viscosity assumption, may be improved and also the possible limitation of such procedures. This, it is suggested, is when, of necessity, the specification of the modelled quantity is by a complicated rate equation. Here the use of the turbulent transport equations as a basis for the model is accepted. However, it is concluded that until the complex and hopefully more general turbulence models can predict relatively uncomplicated flows, with at least as good an accuracy as the simpler models discussed, then their use in such flows is superfluous. Finally, a brief discussion on integral methods suggests, that where a suitable velocity profile family exists, such procedures can form the basis of a fast, simple and accurate method of solution

Modelling of Unsteady, Incompressible Separation on an Aerofoil Using an Inviscid Flow Algorithm. G.U. Aero Report 8412

Presented in this report is a new method for the prediction of unsteady, incompressible separated flow over a two-dimensional aerofoil. The algorithm was developed from an existing unsteady potential flow model and makes use of an inviscid formulation for the flowfield. The aerofoil is represented by vortex panels of linearly varying strength which are piecewise continuous at the corners. Discrete vortices with finite cores are used to model the separating shear layers. Following a brief summary of unsteady separation modelling, the theoretical framework is presented and the subsequent numerical implementation is discussed in detail. Results are given for flows which tend asymptotically to the steady state and conclusions are drawn regarding the usefulness of the method

The Collected Data for Ramp Function Tests on a NACA 23012 Aerofoil. Volume 1: Description and Pressure Data. G.U. Aero Report 8413

Summary: Here in is presented the collected data for tests in which a NACA 23012 aerofoil was subjected to a variety of ramp type displacements in pitch about the quarter chord position. The data clearly illustrates the effect of reduced frequency on the aerofoil characteristics and the chordal pressure distribution at the midspan position of the aerofoil model

A Method for Predicting Unsteady Potential Flow About an Aerofoil. G.U. Aero Report 8401

Summary: A new model is presented for the calculation of the incompressible, inviscid flow around an arbitrary aerofoil undergoing unsteady motion. The technique was developed from the steady flow algorithm of Leishman and Galbraith (1) in which use was made of a linear distribution of panel vorticity. The procedure is in the same class as that of Basu and Hancock (2) but, because of the particular approach to the manner of specifying the shed vorticity, only a set of linear simultaneous equations needs be solved, unlike the method of reference (2), complicated by the necessary solution of a quadratic. A brief history of unsteady flow modelling is given in the introduction, followed by the mathematical details of the current method. Results are presented and discussed for a number of cases which clearly illustrate relevant characteristics of unsteady flow

Data for a NACA 23012C Aerofoil Pitched about its Quarter Chord Axis. Volume I: Pressure data from static and ramp function tests, with photographs of oil-flow visualisation tests

Herein is presented the collected data for tests in which a NACA 23012C aerofoil was subjected to a variety of ramp type displacements in pitch about the quarter chord position at low Reynolds numbers. In addition, the results of static tests and oil-flow visualisation experiments on the aerofoil are displayed

Data for a NACA 23012C Aerofoil Pitched about its Quarter Chord Axis. Volume I: Pressure data from static and ramp function tests, with photographs of oil-flow visualisation tests

Herein is presented the collected data for tests in which a NACA 23012C aerofoil was subjected to a variety of ramp type displacements in pitch about the quarter chord position at low Reynolds numbers. In addition, the results of static tests and oil-flow visualisation experiments on the aerofoil are displayed

Use of a Numerical Model in the Conceptual Design of a New Blade Vortex Interaction Facility. Department of Aerospace Engineering internal report no. 9509

This report describes and presents results from a numerical model developed to aid the preliminary design of a new wind tunnel based blade-vortex interaction (BVI) facility. The proposed facility will simulate tail rotor BVI by interacting a transverse vortex, produced by a single-bladed rotor situated in the wind tunnel contraction, with a blade mounted vertically in the tunnel working section. In the model a three dimensional source panel method is used to calculate the constrained flow through the low speed wind tunnel and a free wake vortex model represents the wake generated by the upstream rotor. Convection of the wake is then determined by superposition of the undisturbed tunnel velocity and the induced velocity components from the wake itself. Results, obtained via a parametric analysis, illustrate the geometry of the wake and tip vortex and their relation to basic design parameters. In particular, two possible operational strategies for the upstream rotor are examined with reference to development of the experimental facility. It is concluded that, while a short duration finite rotor traverse may be the optimum vortex generation strategy, a continuous running rotor may be the most cost effective option