MTR benchmark static calculations with MCNP5 code

With the sustained development in computer technology, the use of more powerful computational tools becomes mandatory. The challenge today is to revisit safety features of the existing nuclear research reactors using new generation of computer tools. The objective is to verify that the safety requirements still met and when necessary to introduce some amendments coming from the new attainments. In the current paper the IAEA safety-related nuclear research reactors (RR) benchmark problem is reconsidered. The idea consists in performing static calculations of the benchmark using the last version of the MCNP5 code. This later offers updated code models and cross-section library. The results are afterwards compared with previous calculations and discussed.     

Mechanical and thermal properties of polyvinylchloride/olive residue flour blends treated by gamma irradiation

In this study, gamma irradiation treatments were used to improve the compatibility between poly(vinyl chloride) (PVC) and olive residue flour (ORF). The blends were subjected to gamma irradiation at doses of 10 and 70 kGy. The mechanical, thermal, and morphological behaviors of those blends have been assessed. The irradiated blends exhibit better thermal properties, higher tensile modulus, elongation, and strength at break than those of unirradiated blends. The contact angle of water on the surface of a blend irradiated at doses of 10 and 70 kGy is smaller than that for their corresponding unirradiated blend. These treatments cause surface oxidation of PVC/ORF films, as revealed by Fourier transform infrared (FTIR) spectroscopy analysis. J. VINYL ADDIT. TECHNOL., 22:273–278, 2016. © 2014 Society of Plastics Engineers     

Hydraulic permeability of structures made of geotextile sand containers: Laboratory tests and conceptual model

The permeability values were obtained for more than 15 different geotextile sand container (GSCs)-structures. The influence of the size of the sand containers (four different sizes were tested), arrangement and geometry was investigated. First results show that the size of the container represents one of the primary factors influencing the permeability but the method of placement of the GSCs also plays a significant role (different methods of placing resulted in a permeability with more than a 50% difference). The results show that the flow through the GSC-structure is solely governed by the gaps between neighbouring containers and that the flow through the sand fill in the containers can be neglected.In addition, several GSC-structures with the same geometry and the same size of containers but with different arrangements (and thus different permeabilities) were tested under wave action in the twin wave flume of LWI. The results show that the mode of placement of elements strongly affects the permeability and the stability of GSC-structures. Placement of the containers in such a way that the contact areas among containers are maximized resulted in the largest overall stability against wave action. A conceptual model for the determination of the permeability of GSC-structures is proposed.     

Enhanced electrocoagulation–electroflotation for turbidity removal by Opuntia ficus indica cladode mucilage

The optimisation of the electrocoagulation‐electroflotation (EC‐EF) process assisted by the mucilage of the Opuntia ficus indica (OFI), on the turbidity removal was performed through the response surface methodology (RSM). For a solution of 300 mg/L of silica gel, high turbidity removal (93.14% ± 1.31) was obtained under the optimal conditions of 2.5 mg/L, 21.2 V, 9.65 and 2.61 mS/cm for the mucilage concentration, voltage, pH and conductivity, respectively, this experimental value was close to the predicted value of 92.96% ± 0.3. OFI mucilage increases turbidity removal efficiency and reduces specific energy consumption at a fixed current density. The turbidity removal of the EC‐EF process was improved by 30.94% compared with the conventional EC–EF (EC–EF without OFI mucilage) which shows 62.02% ± 1.45 of turbidity removal.     

Hybrid Energy System with an Energy Management Control Strategy Based on the Online Fuel Consumption

Abstract

Many agriculture investments are oriented to the Sahara. Noticeably, they need electricity which is often provided by diesel generators. The refueling process is a real economic challenge due to the very remote area distance which makes it very expensive. To overcome this issue, the hybridization is initiated with the renewable solar photovoltaic energy. That marks an excess or a shortage of power; to cope this uncontrolled power a storage system is compulsory. This work is specific to the pumped hydroelectric storage system which is favorable due to its ecological aspects and the subject matter. The proposed management takes into account the solar temporal variation combined to the pumping scheduling time and real-time fuel consumption optimization. This last proves the PSH’s performance dual function in both the irrigation and power restitution; it also reduces the gas emission and saves fuel. As far as this study is concerned, the suggested control is successfully examined through the management strategy in comparison to that of the literature. Consequently, this study could be helpful for similar future studies. Because, it links the diesel efficiency, solar variation, and dynamic load under the constraints of diesel rated power optimal sizing, PV panels surface, and water tank dimension.     

Evaluation using online support-vector-machines and fuzzy reasoning. Application to condition monitoring of speeds rolling process

A method for process condition monitoring and evaluation, which combines the online support vector machine (SVM) regression and the fuzzy sets methods, is proposed. To account for the time dependence, the proposed approach is based on moving windows in order to take into account the past and new data for the model’s adaptation. The fuzzy analysis is then applied to the generated residual data to give an evaluation of the condition monitoring. The proposed approach is applied to hot rolling for constructing a complementary condition monitoring system, which permits an online quality evaluation in the rolling process. Simulation results based on residual data show that the new approach is easily implementable.     

Modelling systems defined by RTD curves

The RTD theory is commonly used for describing flow patterns in a large class of applications, and particularly for ventilated enclosures. Experimental RTD curves are used for modelling these premises with an application in the nuclear industry for predicting the airborne pollutant transfers in order to prevent radiological risk. An approach based on a superstructure involving interlinked elementary flow patterns such as CSTRs, PFRs, recycles and by-passes is implemented. In order to propose a generic and easy to use tool, the associated large-scale MINLP problem is solved by using the GAMS package. After a validation phase on examples with known solutions, a laboratory enclosure, called MELANIE, used in the nuclear industry is modelled. The comparison between experimental RTD curve and the ones obtained from models extracted from superstructures shows good agreement. The superstructure-based solution procedure constitutes an efficient and intermediate way between numerical simulations using CFD codes and experimental determinations of characteristic parameters, which are both difficult to implement in the case of large and cluttered systems which are typical of the nuclear industry.     

Hydrogen consumption and power density in a co-flow planar SOFC

In the present work, power density and hydrogen consumption in a co-flow planar solid oxide fuel cell (SOFC) are studied according to the inlet functional parameters; such as the operational temperature, the operational pressure, the flow rates and the mass fractions of the species. Furthermore, the effect of the cell size is investigated. The results of a zero and a one-dimensional numerical electro-dynamic model predict the remaining quantity of the fed hydrogen at the output of the anode flow channel. The remaining hydrogen quantities and the SOFC's power density obtained are discussed as a function of the inlet functional parameters, the geometrical configuration of the cell and several operating cell voltages values.     

Improvement of electrical arc furnace operation with an appropriate model

Electrical arc furnaces are commonly employed in industry to produce molten steel by melting iron and scrap steel. Furnace control is a necessary operation for production optimization. The principal parameters to be controlled are: maximum productivity requirements, minimum power off time, good power quality and safety. The aim of this study is to achieve all these objectives. Hence, because of the stochastic and dynamic behaviour of the arc during the melting process, a proposed model is checked with measurements at an industrial electrical arc furnace. How electrodes position and transformer taps can affect X and R arc function are discussed in detail. This new operating strategy has been determined taking into account Flicker, melting stages and electrode positions. It is shown that optimum efficiency can be reached by the integration of the proposed model in regulation loop.