Abstract. In this paper, the global existence of smooth solutions for the three-dimensional (3D) non-isentropic bipolar hydrodynamic model is showed when the initial data are close to a constant state. This system takes the form of non-isentropic Euler–Poisson with electric field and frictional damping added to the momentum equations. Moreover, the L-decay rate of the solutions is also obtained...

A two-layer Hamiltonian toy model consisting of two isentropic stratospheric layers is simplified using perturbation analysis while preserving the Hamiltonian structure. These two layers are neutrally and stably stratified. The first approximation applies when the Froude number of the upper isentropic layer is small, such that the upper surface is approximately rigid, and this upper layer is mu...

Batch melting of ascending mantle can be approximated as an isentropic process, since on the time scale of melting heat flow into or out of source regions will typically be negligible and the process is slow enough to be close to reversible. Similarly, fractional fusion can be idealized as a series of incremental isentropic melting steps, although the entropy of the residue decreases in each st...

Isentropic transport and mixing are important processes for the distribution of chemical constituents in the mid-to-high latitudes. A new framework is introduced to quantify both isentropic transport and isentropic mixing in a modified Lagrangian coordinate. The framework is applied to quantify the transport and mixing associated with the two types of Rossby wave breaking (i.e. cyclonic and ant...

In this paper, we first generalize the classical results on Cauchy problem for positive symmetric quasilinear systems to more general Besov space. Through this generalization, we obtain the local well-posedness with initial data in the space B d 2 +1 2,1 (R ) which has critical regularity index. We then apply these results to give an explicit characterization on the Isentropic approximation for...

The impulse turbo expander (ITE) is employed to replace the throttling valve in the vapor compression refrigeration cycle to improve the system performance. An improved ITE and the corresponding cycle are presented. In the new cycle, the ITE not only acts as an expansion device with work extraction, but also serves as an economizer with vapor injection. An increase of 20% in the isentropic effi...

resource allocation and optimal leveling are among the top challenges in project management. this paper presents a dea-based procedure for determining an optimal level of inputs to produce a fixed level of outputs. to achieve this goal, we assume that the levels of outputs can be forecasted in the next season and the procedure will determine optimal level of inputs for all dmus. such as some of...

The dependence of some thermodynamic properties of spin-polarized liquid 3He such as velocity of sound, adiabatic index, isentropic compressibility and temperature on the spin polarization has been investigated along different isentropic paths. The Lennard-Jones potential has been used in our calculations. It has been found that for higher values of entropy, the spin polarization has greate...

To achieve multi-objective aerodynamics design optimization for a 1.5-stage transonic compressor, platform incorporating blade parameterization methods, BPNN surrogate model, and the NSGA-II method was developed. The stagger angle distribution of three rows selected as variable, with isentropic efficiency at new condition stall margin set goal functions. Results demonstrated that, without alter...