Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 11 of 11 for “"Rapid Distortion Theory"”.
-
Large Eddy Simulation of Shear-Free Interaction of Homogeneous Turbulence with a Flat-Plate Cascade
… develop a computational technique to predict the distortion of homogeneous isotropic turbulence as it passes through a cascade of thin flat plates. We use Large-Eddy Simulation (LES) to capture the spatial development of the incident turbulence and its interaction with the plates which are assumed …
-
Structure and Turbulence of the Three-Dimensional Boundary Layer Flow over a Hill
… flows are built on two-dimensional turbulence theory, limiting the accuracy of simulation results. To improve the accuracy of turbulence modeling capabilities, a better understanding of 3DTBL physics is required. This dissertation outlines the experimental investigation of the attached 3D TBL …
-
Turbulence Interaction in a Highly Sataggered Cascade-Propulsor Configuration
… been taken. Predictions of the same flow using Rapid Distortion Theory (RDT) were performed. Measurements and predictions were compared. The comparison was oriented to check the aptness of RDT in describing this kind of flow. Since this study represents the initial steps of a major project, the …
-
Differential Diffusion of Scalars in Sheared, Stratified Turbulence
To determine why differential diffusion occurs, rapid distortion theory (RDT) is used. To determine where differential diffusion occurs in the target parameter space, laboratory experiments are employed. RDT confirmed previous explanations that differential diffusion occurs because of excess …
-
Asymptotic approximations for the sound generated by aerofoils in unsteady subsonic flows
… interactions in steady uniform flows using rapid distortion theory, and has focused on aerofoils with simple geometries. We extend this to deal with aerofoils with more realistic geometries (by including camber, thickness, and angle of attack), as well as considering the new topic of …
-
Acoustic Scattering in Sheared Flow
… mathematical framework through an application of Rapid Distortion Theory, considering linearised perturbations to a transversely sheared background flow. Within this framework, the development of disturbances within a boundary-layer are investigated, both hydrodynamic and acoustic, over a variety …
-
Advanced Instrumentation and Measurements Techniques for Near Surface Flows
… profile is consistent with the prediction of Rapid Distortion Theory (RDT), confirming that the redistribution of normal stresses is an inviscid effect. The fluctuating component of the phase- averaged turbulent boundary layer profiles is described using the exact solution to laminar Stokes …
-
Large Scale Homogeneous Turbulence and Interactions with a Flat-Plate Cascade
… data was compared to linear cascade theory and showed good qualitative agreement, especially for wavenumbers above the region of influence of the wind tunnel and turbulence generator effects. As predicted, the turbulence is permanently modified by the presence of the cascade after …
-
Kinematic simulation of turbulent flow and particle motions
… particle dispersion in turbulent flow (e.g. K-theory and Random Flight) but they make assumptions about the fluid-particle interaction and require empirical coefficients. Theoretical work on the motion of bubbles and varticles in idealised flows has shown that the instantaneous structure of the …
-
Turbulence ingestion noise of open rotors
… atmospheric turbulence, known as Unsteady Distortion Noise (UDN), is likely to be higher for open rotors than for conventional turbofan engines since the rotors are fully exposed to oncoming turbulence and lack ducting to attenuate the radiated sound. However, UDN has received less …
-
An Experimental Investigation of Unsteady Surface Pressure on Single and Multiple Airfoils
… in turbulence and comparisons with inviscid theory are presented with the goal of determining the effect of angle of attack on an airfoils inviscid response. Unsteady measurements made on the surface of a linear cascade immersed in periodic flow are presented and analyzed to determine the …