Efficiency of a gyroscopic device for conversion of mechanical wave energy to electrical energy:Technical report from ESGI-83 workshop in industrial mathematics 2011

We consider a recently proposed gyroscopic device for conversion of mechanical ocean wave energy to electrical energy. Two models of the device derived from standard engineering mechanics from the literature are analysed, and a model is derived from analytical mechanics considerations. From these models, estimates of the power production, efficiency, forces and moments are made. We find that it is possible to extract a significant amount of energy from an ocean wave using the described device. Further studies are required for a full treatment of the device.Resulting from the interaction with Joltech A/S at ESGI-83 (European Study Group with Industry) workshop on industrial mathematics, Sønderborg Denmark, 2011.</p

Discretizations in isogeometric analysis of Navier-Stokes flow

Abstract This paper deals with isogeometric analysis of the 2-dimensional, steady state, incompressible Navier-Stokes equation subjected to Dirichlet boundary conditions. We present a detailed description of the numerical method used to solve the boundary value problem. Numerical infsup stability tests for the simplified Stokes problem confirm the existence of many stable discretizations of the velocity and pressure spaces, and in particular show that stability may be achieved by means of knot refinement of the velocity space. Error convergence studies for the full Navier-Stokes problem show optimal convergence rates for this type of discretizations. Finally, a comparison of the results of the method to data from the literature for the the lid-driven square cavity for Reynolds numbers up to 10,000 serves as benchmarking of the discretizations and confirms the robustness of the method