Peer review is an essential part in the publication process, ensuring that Journal of Marine Science and Engineering maintains high quality standards for its published papers.[...]

Peer review is an essential part in the publication process, ensuring that Journal of Marine Science and Engineering maintains high quality standards for its published papers.[...]

This work reports three-dimensional simulation results of thermal mixing in rectangular T-junction configuration at high Reynolds number. The validation data are provided by an experimental study done at the Department of Mechanical Engineering of Mie University, Japan. The T-Junction was selected as a benchmark for thermal mixing in the ERCOFTAC Workshop held in EDF Chatou, France, 2011. Reynolds Averaged Navier-Stokes (RANS), Unsteady Reynolds Averaged Navier-Stokes (URANS) and Scale-Adaptive Simulation (SAS) were performed with CFD code using finite volume method. Velocity and thermal field as well as the turbulent stresses are reported and compared to experimental data in several longitudinal stations. It was found from the comparison that URANS methodology can’t reproduce the striping phenomenon and secondly that SAS model fit better than SST model with experimental data. Additional contours of averaged longitudinal velocity end thermal field as well as the flow structures developing in the channels are presented and discussed.

A novel hydrophilic bi-component collodion composite membrane for ultrafiltration was prepared from an asymmetric polyester-coated technological support coated with a thin layer of two polyetherimide and polysulfone (PEI / PSU) physical copolymers. The influence of the mass percentage of each copolymer is a significant effect on the hydrodynamic properties of the membrane.

The present paper is focused on the sensitivity analysis of California line source model 4 (CALINE4) and Industrial source complex short-term model 3 (ISCST3) by changing one input variable at a time while keeping other variables as constant to identify the effect of each input variable on predicted PM10 and NOx concentrations. State Highway (SH-17) length of 3.3 km passing through the industrial area of Mysuru with six receptor points has been considered in the present study. The sensitivity analysis of CALINE4 and ISCST3 model showed pollutant concentrations were more influenced by meteorological factors such as wind speed, wind direction, atmospheric stability conditions; source strength such as traffic volume, emission factors (WEF) and pollutants emission rates. However, it was also found that pollutant concentrations were less influenced by mixing height, road width, and surface roughness coefficient.

In this numerical study two configurations are considered, the first configuration in natural convection corresponds to a closed cavity equipped with a heating bar and the second mixed configuration corresponds to the same cavity but ventilated. The flow is turbulent (GrH = 1,2.108), a choice of model is very important. The turbulence model chosen for natural convection is the low-Reynolds k-ε model. A comparison of the turbulence models led us to choose the RNG k-ε model for mixed convection study, because it is the suitable model for flows in ventilated cavities as well as flows with recirculation. Ventilation effect on natural flow has been studied by analyzing flow dynamic and thermal structure. Nusselt average number on each bar face is found to be improved by jet injection into the ventilated cavity, from about 50% to 60%. This comparison reveals the different velocities influence of the incoming air jet on the confined cavity flow structure, or this jet succeeds in breaking the single-cell flow of natural convection case into a multicellular flow for the other case of mixed convection at high velocities above the heating bar, of which it is the main purpose of this study.

Our research consists in studying the pre-feasibility of a hybrid PV / H2 hydrogen PV system for a remote residential area located at GPS coordinates (30.203584, -9.425989) in the south of Morocco. We are in a situation of solar energy prediction in order to integrate it into the Microgrid and, subsequently, to establish an evaluation of the electricity storage potential in the form of hydrogen produced by an electrolyser. Several technical studies are now being conducted on each of the components of our system that includes a PV electrolyser and a fuel cell. The electrolyser produces hydrogen from the excess energy provided by the PV. When the need for the charges exceeds the PV output, the fuel cell consumes the hydrogen gas to provide additional energy. The proposed Microgrid will constitute a reference and a decision tool for optimal sizing of its subsystems. To compensate for the investment risk resulting from a gap between prediction and actual operation, further study is to be expected taking into account two criteria: the cost of kWh and energy efficiency.

The recent energy dependence and climate change policies encourage development and utilization of renewable and clean energy forms worldwide. After solar and wind, biomass as source of biofuels is attracting an increased interest because of the diversity of biofuels that can be produced from this renewable resource. Among the vast array of biomasses available (waste biomass, lignocellulosic biomass, etc.), algae are regarded as the only source of renewable biofuels capable to meet the global demand for biofuels mainly for transport. Depending on the used technology, microalgal biomass can be used to produce at least 6 forms of biofuels: biodiesel, bio-oil, bioethanol, jet fuel, hydrogen and biogas, some of them are yet produced at large scale. This paper will provide an extensive review of the biofuels produced from microalgal biomass, named third generation biofuels and analyze the possibility to develop such activity in Morocco.

The VO(OH)-assisted letrozole electrochemical determination has been analyzed and evaluated by theoretical point of view. The electrochemical determination is realized by a cathodic process, in which vanadium (III) oxyhydroxide plays the role of active substance and proton-electron transfer mediator. The correspondent mathematical model has been analyzed and evaluated by means of linear stability theory and bifurcation analysis. It was shown that VO(OH) may be an excellent electrode modifier for the letrozole electrochemical determination in neutral and mildly acidic pH conditions. The oscillatory behavior in neutral media is less probable than in acidic media

Perrenial alfalfa is widley used in the Saharan regions of Algeria. In weltands, yields are acceptable, whereas in semi-arid to arid areas irrigation is required. But in water scarcity case and large population growth, the urban sector is fovored compared to the agricultural sector. In front of this situation, the use of cubic meters of irrigation water for optimum sustainble production is discussed. Alfalfa considered to be a drought-adapted species is covering and contributes to the sustainability of rainfall systems. Its behavior is a function of, among other things, the water regime. The choice of cultivars that meet these characteristcs must be tested under extreme conditions. For these goals, under Lower-Cheliff climatic conditions, sixteen cultivars are tested over four years of experimentation, in two trials under two water regimes, one in rainfed and the other in maximum evapotranspiration conditions. The variance analysis and discriminant factorial analysis showed a multiannual bahavior variability of the parameters studied. This variability seems to be depending on the cultivars, year of production, the water regime and climatic conditions. Thus, Ameristand 801S, Ecotipo siciliano, Mamuntanas and Erfoud1, have adapted well to the climate of Lower-Cheliff. However, Tamantit, Africaine and Prosementi were badly acclimated.