Investigation of the Orthogonal Blade-Vortex Interaction 2nd Interim Report. G.U. Aero Report 0103

Preliminary results from a PIV study of the orthogonal blade-vortex interaction are presented. This report presents a comparison of the details of the orthogonal BVI over the lower and upper surfaces of the blade. Detailed differences in the mechanics of these interactions have been noted. Features of the vortex behaviour in the wake of the blade are also presented together with the results obtained at very close proximity to the blade surface

Investigation of the Orthogonal Blade-Vortex Interaction 1st Interim Report. G.U. Aero Report 0210

Steps towards the implementation of a stereoscopic particle image velocimetry (PIV) system for the investigation of the orthogonal blade-vortex interaction are described. The design of the stereo PIV system used is described, and details of the Scheimpflug camera mounts are provided. The necessary changes to the image capture and calibration procedures are described, and brief details of the stereo PIV analysis are given. This is essential preparatory work for the experimental study of the orthogonal blade-vortex interaction using stereoscopic PIV to take place later in this project

Investigation of the Orthogonal Blade-Vortex Interaction 2nd Interim Report. G.U. Aero Report 0303

Steps towards the implementation of a stereoscopic particle image velocimetry (PIV) system for the investigation of the orthogonal blade-vortex interaction are described. The accuracy of the 2D PIV system has been reassessed in the light of the greater accuracy demands of stereo PIV. The improvement to the perceived quality of the PIV vector map from a discrete window offset algorithm was investigated, and it was observed that significant improvements were made in the critical vortex core region

Investigation of the Orthogonal Blade-Vortex Interaction 1st Interim Report. G.U. Aero Report 0012

Preliminary results from a PIV study of the orthogonal blade-vortex interaction are presented. The tests have focussed upon phenomena occurring over the lower and upper surfaces of the blade. An analysis of the BVI over the upper surface has revealed an inflow to the vortex core, which contrasts with the radial outflow previously observed over the lower surface

Investigation of the Orthogonal Blade-Vortex Interaction 1st Interim Report. G.U. Aero Report 0210

Steps towards the implementation of a stereoscopic particle image velocimetry (PIV) system for the investigation of the orthogonal blade-vortex interaction are described. The design of the stereo PIV system used is described, and details of the Scheimpflug camera mounts are provided. The necessary changes to the image capture and calibration procedures are described, and brief details of the stereo PIV analysis are given. This is essential preparatory work for the experimental study of the orthogonal blade-vortex interaction using stereoscopic PIV to take place later in this project

Open-closed duality and Double Scaling

Nonperturbative terms in the free energy of Chern-Simons gauge theory play a key role in its duality to the closed topological string. We show that these terms are reproduced by performing a double scaling limit near the point where the perturbation expansion diverges. This leads to a derivation of closed string theory from this large-N gauge theory along the lines of noncritical string theories. We comment on the possible relevance of this observation to the derivation of superpotentials of asymptotically free gauge theories and its relation to infrared renormalons.Comment: 10 pages, LaTe

Probing the fuzzy sphere regularisation in simulations of the 3d \lambda \phi^4 model

We regularise the 3d \lambda \phi^4 model by discretising the Euclidean time and representing the spatial part on a fuzzy sphere. The latter involves a truncated expansion of the field in spherical harmonics. This yields a numerically tractable formulation, which constitutes an unconventional alternative to the lattice. In contrast to the 2d version, the radius R plays an independent r\^{o}le. We explore the phase diagram in terms of R and the cutoff, as well as the parameters m^2 and \lambda. Thus we identify the phases of disorder, uniform order and non-uniform order. We compare the result to the phase diagrams of the 3d model on a non-commutative torus, and of the 2d model on a fuzzy sphere. Our data at strong coupling reproduce accurately the behaviour of a matrix chain, which corresponds to the c=1-model in string theory. This observation enables a conjecture about the thermodynamic limit.Comment: 31 pages, 15 figure