Physics of shock waves and high-temperature hydrodynamic phenomena - Ya.B. Zeldovich and Yu.P. Raizer (translated from the Russian and then edited by Wallace D. Hayes and Ronald F. Probstein); Dover Publications, New York, 2002, 944 pp., $34.

Xiangshan Bay is a semi-enclosed bay in China, in which tidal flats have been substantially reclaimed to support the development of local economies and society over previous decades. The loss of tidal flats has led to changes of tides and locally suspended sediment in the bay. The effects of tidal flat reduction on locally suspended sediment dynamics was investigated using a numerical model forced by tidal data and calibrated by observed tidal elevation and currents. The model satisfactorily reproduces observed water levels, currents, and suspended sediment concentration in the estuary, and therefore is subsequently applied to analyze the impact of tidal flat reclamation on locally suspended sediment transport. After the loss of the tidal flats from 1963 to 2010, the suspended sediment concentrations (SSC) at the bottom boundary layer were reduced/increased in the outer bay/tidal flat areas due to weakened tidal currents. In the inner bay, the SSC values near the bottom level increased from 1963 to 2003 due to the narrowed bathymetry, and then decreased from 2003 to 2010 because of the reduced tidal prism. The model scenarios suggest that: (1) a reduction of tidal flat areas appears to be the main factor for enhancing the transport of sediments up-estuary, due to the increased Eulerian velocity and tidal pumping; (2) A reduction of tidal flat areas impacts on spatial and temporal SSC distribution: reducing the SSC values in the water areas due to the reduced current; and (3) a tidal flat reduction influences the net sediment fluxes: lessening the erosion and inducing higher/lower landward/seaward sediment transportation.

Responses of water environment to tidal flat reduction in Xiangshan Bay: Part II locally re-suspended sediment dynamics

Wide range scaling laws for radiation driven shock speed, wall albedo and ablation parameters for high-Z materials

Analytical benchmark for non-equilibrium radiation diffusion in finite size systems

Positive effect of a canal system and reservoir group on the spatial-temporal redistribution of water resources in a pinnate drainage pattern.

Fully implicit 1D radiation hydrodynamics: Validation and verification

Investigation of various methods for wall loss reduction in Inertial Confinement Fusion hohlraums

Detailed radiation hydrodynamic simulations are carried out to investigate the x-ray emission process in four high-Z planar targets, namely, tungsten (W), gold (Au), lead (Pb), and uranium (U) irradiated by 1 ns, 351 nm flat top laser pulses. A thorough zoning analysis is performed for all laser-driven high-Z foils over a wide intensity range of [Formula: see text] W/cm2 with appropriately chosen photon energy range and recombination parameter. The resulting variation of conversion efficiency over the full intensity range exhibits an optimum for all materials, which is explained by considering the characteristic emission contributions from two different regions of laser irradiated plasma, namely, conversion layer and re-emission zone. A new generalized single scaling relation based upon smooth broken power law is proposed for conversion efficiency variation along with the separate determination ( ηS, ηM) in soft and hard/M-band x-ray regions. It has been observed that ηS for Pb and W always lies in between that for Au and U for intensities smaller than [Formula: see text] W/cm2. On further increase in intensity, ηS is observed to be maximum for Au and U, whereas it is minimum for W. Significant contribution to M-band conversion efficiencies is observed in all elements for intensities higher than [Formula: see text] W/cm2 with maximum and minimum values attained by W and U, respectively. The results are explained by considering the contributions from the emission coefficients of all materials in both conversion layer and re-emission zone up to corresponding photon cutoff energies at different laser intensities.

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Karabi Ghosh

Papers

Fully implicit 1D radiation hydrodynamics: Validation and verification

Wide range scaling laws for radiation driven shock speed, wall albedo and ablation parameters for high-Z materials

Analytical benchmark for non-equilibrium radiation diffusion in finite size systems

Investigation of various methods for wall loss reduction in Inertial Confinement Fusion hohlraums

Detailed investigation on x-ray emission from laser-driven high-Z foils in a wide intensity range: Role of conversion layer and re-emission zone