Numerical simulation research on ecological protection device for marine water intake engineering based on cfd

1941-1948The ecological protection originated from marine engineering is the key factor for the healthy and sustainable development of marine ecological system. Combined with the tidal dynamic characteristics, a new optimistic ecological protection device concept model is designed for marine water intake engineering to avoid the ecological loss, which following the principles of safe, stable, easy installation and maintenance, unaffected water intake. Based on computational fluid dynamics (CFD), the three dimensional mathematical model of ecological protection device for marine water intake engineering is constructed to simulate and evaluate the feasibility of the proposed device. The flow field and pressure distribution are simulated and analyzed before and after the device installation. The numerical results of flow velocity in the intake, intake box and intake channel show that the ecological protection device has a weak effect on the flow field and the device can provide ecological safeguard for marine intake engineering. The pressure distribution from the ecological protection device would also reflect the underlying reason of the flow velocity change

Determination of Superconducting Gap of SmFeAsFxO1-x Superconductors by Andreev Reflection Spectroscopy

The superconducting gap in FeAs-based superconductor SmFeAs(O1-xFx) (x = 0.15 and 0.30) and the temperature dependence of the sample with x = 0.15 have been measured by Andreev reflection spectroscopy. The intrinsic superconducting gap is independent of contacts while many other "gap-like" features vary appreciably for different contacts. The determined gap value of 2D = 13.34 +/-0.47 meV for SmFeAs(O0.85F0.15) gives 2D/kBTC = 3.68, close to the BCS prediction of 3.53. The superconducting gap decreases with temperature and vanishes at TC, in a manner similar to the BCS behavior but dramatically different from that of the nodal pseudogap behavior in cuprate superconductors.Comment: 13 pages, 9 figures, Special Issue of Physica C on Superconducting Pnictide

Research on multi-parameter stepwise coupling inversion method for marine integrated element water quality model based on data-driven and genetic calculation

1546-1561In this method, there are two inversion phases step by step, namely, preliminary inversion and precise inversion. Preliminary inversion is implemented by coupling data-driven model with Marine Integrated Element Water Quality Model (MIEWQM), to determine the relationship between the multi-parameter and the pollution concentration values in gauge stations. Field data are inputted the relationship to obtain the initial values of multi-parameter matching. MIEWQM is embedded into Genetic Algorithms (GAs) to search global multi-parameter optimal values in the precise inversion. Preliminary inversion provides the initial values of multi-parameter matching to the precise inversion for shortening the value-taking range of population in GAs. Case studies in Bohai Bay, China. An “identical twin experiment” method and a practical application with Dissolved Inorganic Nitrogen (DIN) are used to verify the present method