Coupled Fluids-Radiation Analysis of a High-Mass Mars Vehicle

The NEQAIR line-by-line radiation code has been incorporated into the DPLR Navier-Stokes flow solver such that the NEQAIR subroutines are now callable functions of DPLR. The coupled DPLR-NEQAIR code was applied to compute the convective and radiative heating rates over high-mass Mars entry vehicles. Two vehicle geometries were considered - a 15 m diameter 70-degree sphere cone configuration and a slender, mid-L/D vehicle with a diameter of 5 m called an Ellipsled. The entry masses ranged from 100 to 165 metric tons. Solutions were generated for entry velocities ranging from 6.5 to 9.1 km/s. The coupled fluids-radiation solutions were performed at the peak heating location along trajectories generated by the Traj trajectory analysis code. The impact of fluids-radiation coupling is a function of the level of radiative heating and the freestream density and velocity. For the high-mass Mars vehicles examined in this study, coupling effects were greatest for entry velocities above 8.5 km/s where the surface radiative heating was reduced by up 17%. Generally speaking, the Ellipsled geometry experiences a lower peak radiative heating rate but a higher peak turbulent convective heating rate than the MSL-based vehicle

Schubert, Gunter and Jens Damm Eds. Taiwanese Identity in the Twenty-first Century: Domestic, Regional and Global Perspectives, Abingdon: Routledge. 2011.

Book review

A Conservative Finite Difference Scheme for Poisson-Nernst-Planck Equations

A macroscopic model to describe the dynamics of ion transport in ion channels is the Poisson-Nernst-Planck(PNP) equations. In this paper, we develop a finite-difference method for solving PNP equations, which is second-order accurate in both space and time. We use the physical parameters specifically suited toward the modelling of ion channels. We present a simple iterative scheme to solve the system of nonlinear equations resulting from discretizing the equations implicitly in time, which is demonstrated to converge in a few iterations. We place emphasis on ensuring numerical methods to have the same physical properties that the PNP equations themselves also possess, namely conservation of total ions and correct rates of energy dissipation. We describe in detail an approach to derive a finite-difference method that preserves the total concentration of ions exactly in time. Further, we illustrate that, using realistic values of the physical parameters, the conservation property is critical in obtaining correct numerical solutions over long time scales

On the Tails of the Limiting QuickSort Density

We give upper and lower asymptotic bounds for the left tail and for the right tail of the continuous limiting QuickSort density f that are nearly matching in each tail. The bounds strengthen results from a paper of Svante Janson (2015) concerning the corresponding distribution function F. Furthermore, we obtain similar upper bounds on absolute values of derivatives of f of each order

Coupled Fluids-Radiation Analysis of a High-Mass Mars Entry Vehicle

The NEQAIR line-by-line radiation code has been incorporated into the DPLR Navier-Stokes flow solver such that the NEQAIR subroutines are now callable functions of DPLR. The coupled DPLR-NEQAIR code was applied to compute the convective and radiative heating rates over high-mass Mars entry vehicles. Two vehicle geometries were considered - a 15 m diameter 70-degree sphere cone configuration and a slender, mid-L/D vehicle with a diameter of 5 m called an Ellipsled. The entry masses ranged from 100 to 165 metric tons. Solutions were generated for entry velocities ranging from 6.5 to 9.1 km/s. The coupled fluids-radiation solutions were performed at the peak heating location along trajectories generated by the Traj trajectory analysis code. The impact of fluids-radiation coupling is a function of the level of radiative heating and the freestream density and velocity. For the high-mass Mars vehicles examined in this study, coupling effects were greatest for entry velocities above 8.5 km/s where the surface radiative heating was reduced by up 17%. Generally speaking, the Ellipsled geometry experiences a lower peak radiative heating rate but a higher peak turbulent convective heating rate than the MSL-based vehicle

4-{(E)-N′-[2-(8-Quinolyloxy)acetyl]hydrazonomethyl}benzoic acid methanol solvate

In the title compound, C19H15N3O4·CH4O, the mean planes of the benzene ring and the quinoline system make a dihedral angle of 6.7 (2)°. The acetohydrazide host mol­ecules are connected via inter­molecular O—H⋯O hydrogen bonds into two-dimensional zigzag sheets extending in the ab plane. The methanol solvent mol­ecule is linked to the host mol­ecule via inter­molecular N—H⋯O and O—H⋯N hydrogen bonds

(E)-6-Chloro-N′-(3,5-dichloro-2-hydroxy­benzyl­idene)­nicotinohydrazide

The title Schiff base compound, C13H8Cl3N3O2, was synthesized by the condensation reaction of 3,5-dichloro­salicyl­aldehyde with 6-chloro­nicotinic acid hydrazide in 95% ethanol. The mol­ecule is nearly planar, with a dihedral angle of 1.9 (2)° between the aromatic ring planes, and an intra­molecular O—H⋯N hydrogen bond is observed. In the crystal, the mol­ecules are connected by inter­molecular N—H⋯O hydrogen bonds into infinite chains propagating in [100]