A Brayton cycle with, external and internal irreversibilities, is analyzed. Optimization of the dimensionless work with respect to two parameters: the isentropic temperatures ratio and the allocation ratio of the heat exchangers, is performed. The qualitative and asymptotic behaviour of the coupled optimal analytic expressions obtained are presented. Using realistic numerical values of the isen...

Although Geostationary Operational Environmental Satellite (GOES) sounding observations of moisture are unique in their ability to depict the pre-convective environment at high temporal and spatial resolutions in three-dimensions, new approaches are needed to more fully take advantage of this highly under-utilized dataset. The NearCast model is a Lagrangian trajectory model that has been develo...

We establish the vanishing viscosity limit of the Navier-Stokes equations to the isentropic Euler equations for one-dimensional compressible fluid flow. For the NavierStokes equations, there exist no natural invariant regions for the equations with the real physical viscosity term so that the uniform sup-norm of solutions with respect to the physical viscosity coefficient may not be directly co...

We propose a new approach for analyzing multi-scale properties of the atmospheric flow that employs the recently introduced isentropic streamfunction and relies on its scale decomposition with Haar wavelets. We applied this method to a cloud resolving simulation of a planetary Walker Cell characterized by pronounced multi-scale flow. The resulting set of isentropic streamfunctions – obtained at...

This paper analyzes synoptic-scale trough-thinning processes using a filamentation time diagnostic. The filamentation time diagnostic is derived from the potential vorticity equation expressed in spherical coordinates in the horizontal plane and the isentropic coordinate in the vertical direction. The diagnostic is an accurate measure of stirring processes under the condition of ‘‘slowly varyin...

An all speed scheme for the Isentropic Euler equation is presented in this paper. When the Mach number tends to zero, the compressible Euler equation converges to its incompressible counterpart, in which the density becomes a constant. Increasing approximation errors and severe stability constraints are the main difficulty in the low Mach regime. The key idea of our all speed scheme is the spec...

The one–dimensional differential equations for the conservation mixture mass and mixture momentum coupled by a relative velocity conservation equation have been solved for an isentropic mixture of gas and liquid two–phase flow. Under certain restrictions the resulting system of partial differential equations is hyperbolic and allow discontinuous solutions. These equations have been solved by th...

Both the porous medium equation and the system of isentropic Euler equations can be considered as steepest descents on suitable manifolds of probability measures in the framework of optimal transport theory. By discretizing these variational characterizations instead of the partial differential equations themselves, we obtain new schemes with remarkable stability properties. We show that they c...

Centrifugal compressors are used in a large number of different compression applications. This tutorial addresses applications for centrifugal compressors in the upstream and midstream sector, such as LNG compression, refrigeration, pipeline compression, compression for gas injection, gas lift, gas gathering, export compression, air compression, and others. The focus is on the specific compress...