The use of a boundary layer in sliding-mode control has been a common technique to reduce chattering of the control signal. However, different choices of the boundary layer width lead to conflicting effects: a large/small boundary layer width can more/less effectively alleviate the chattering phenomenon, but leads to less/more accurate control results. This note proposes online adjusting the wi...

I discuss the results of simplified three dimensional magnetohydrodynamic simulations of the boundary layer between a disc and a non-rotating, unmagnetized star. Strong magnetic fields, possibly approaching equipartition with the thermal energy, occur in the boundary layer due to the shearing of disc-generated fields. The mean boundary layer magnetic field, which is highly variable on an orbita...

Improve the understanding of cloud and boundary layer processes within the littoral through the use of the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS) and relevant observations. Improve the moist and boundary layer physics schemes used in COAMPS based on knowledge gained through extensive testing and verification of high-resolution (1-20 km horizontal grid spacing) numerical s...

This paper presents numerical solutions and idealized analytical solutions of axisymmetric, f -plane models of the tropical cyclone boundary layer. In the numerical model, the boundary layer radial and tangential flow is forced by a specified pressure field, which can also be interpreted as a specified gradient balanced tangential wind field vgr(r) or vorticity field ζgr(r). When the specified ...

where CP is the cavity of P and BP the ball of P . We derive two algorithms to compute Cp. The first algorithm is tuned to be a fast point reprojection to the geometry even in the presence of a boundary layer mesh. The second one is tuned to generate boundary layer meshes for complex geometries. We show how quasistructured elements can be enforced. In addition, enhancements as multi-normals can...

Baroclinic eddy equilibration and the roles of different boundary layer processes in limiting the baroclinic adjustment are studied using an atmosphere–ocean thermally coupled model. Boundary layer processes not only affect the dynamical constraint of the midlatitude baroclinic eddy equilibration but also are important components in the underlying surface energy budget. The authors’ study shows...

Boundary layer structure and decoupling from synoptic scale flow during NAMBLEX E. G. Norton, G. Vaughan, J. Methven, H. Coe, B. Brooks, M. Gallagher, and I. Longley School of Earth, Atmospheric and Environmental science, University of Manchester, Building Sackville Street, Manchester, M60 1QD, UK Department of Meteorology, University of Reading, PO Box 243, Earley Gate, Reading, RG6 6BB, UK Sc...

Numerical models of thermally activated convective flow in Earth's mantle do not resemble active plate tectonics because of their inability to model successfully the process of subduction, other than by the inclusion of artificial weak zones. Here we show, using a boundary layer argument, how the "rigid lid" style of convection favored by thermoviscous fluids leads to lithospheric stresses whic...