We study the Casimir force on a single surface immersed in an inhomoge-neous medium. Specifically we study the vacuum fluctuations of a scalar field with a spatially varying squared mass, m 2 + λ∆(x − a) + V (x), where V is a smooth potential and ∆(x) is a unit-area function sharply peaked around x = 0. ∆(x − a) represents a semi-penetrable thin plate placed at x = a. In the limits {∆(x−a) → δ(...

Recent work has produced a theory for tropical convective available potential energy (CAPE) that highlights the Clausius-Clapeyron (CC) scaling of the atmosphere’s saturation deficit as a driver of increases in CAPE with warming. Here we test this so-called “zero-buoyancy” theory for CAPE by modulating the saturation deficit of cloud-resolving simulations of radiative-convective equilibrium in ...

The heating of the solar corona and the puzzle of the slender high reaching magnetic loops seen in observations from the Transition Region And Coronal Explorer(TRACE) has been investigated through 3D numerical simulations, and found to be caused by the well observed plasma flows in the photosphere displacing the footpoints of magnetic loops in a nearly potential configuration. It is found that ...

A new collocated finite volume-based solution procedure for predicting viscous compressible and incompressible flows is presented. The technique is equally applicable in the subsonic, transonic, and supersonic regimes. Pressure is selected as a dependent variable in preference to density because changes in pressure are significant at all speeds as opposed to variations in density which become v...

The analytic properties of adjoint solutions are examined for the quasi-onedimensional Euler equations. For shocked flow, the derivation of the adjoint problem reveals that the adjoint variables are continuous with zero gradient at the shock, and that an internal adjoint boundary condition is required at the shock. A Green’s function approach is used to derive the analytic adjoint solutions cor...

We exploit a generic instability in the integration of steady, sonic, near-isothermal flows to find the complete transition diagram for recombination fronts (for a model system of equations). The instability requires the integration of the flow equations for speeds between the isothermal and adiabatic sound speeds to be performed with particular care. As a result of this, the previous work of N...

Abstract: This paper reports about progress in the development of numerical tools for adaptive aerodynamic configuration design. We try to illustrate the use of new software components allowing for the parameterized modelling of boundary conditions and the simulation of compressible steady and unsteady viscous flows including a computational flow control model. A coupling of these tools and the...