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In order to describe the behavior and the performance of the photovoltaic modules we can found in the literature different equivalent circuit models such us: single diode model (SDM), double diode model (DDM), three diode model (TDM). Almost of the authors obtained that the SDM is the best solution to describe the electrical characterization of the PV modules. The PV parameters can be extracted by three common approaches: Analytical based on the derivation of mathematical equations, Numeric or iterative usually use non-linear optimization techniques, among all the technique the Newton Raphson is widely used. The last one is meta-heuristic approach characterized by their global search point and their soft computing algorithms. The aim of this study is to explore and discuss the behavior of the single-diode model, which require five parameters are estimated using Particle Swarm Optimization approach. The performance of this method is evaluated using the experimental values of R.T.C France PV cell at irradiation G = 1000 W/m2 and at temperature T = 33 °C. The obtained results are also compared with results of the others computing approach. After this study, we can conclude that the proposed PSO method has the best performance because the RMSE obtained using this approach is around the 1.73.10−4 A and low than those obtained through all compared algorithms.

The degradation cost of air pollution is estimated to be 1.62 percent of Morocco's Gross Domestic Product. Several studies focused on the high-resolution spatial modeling effect. As a result, in this study, we investigated the CHIMERE model performances in Agadir city using two resolutions, C1(0.1°=11 km) and C3 (0.02°=2 km). The numerical results are compared to ozone monitoring data for spring/summer 2010. The results show that the statistical performance improves for the C3, which improves the model's ozone forecasting. Given the seasonal performance differences, future efforts should concentrate on upgrading the quality of input data to provide more accurate information.

In this paper, the dynamic modelling of the thermal behaviour and the electrical characterisation of a PV module are presented. The simulation results of the prediction of the PV module internal te...

Port constructions (quay and dike) require an enormous consumption of materials, in particular concrete and its components, as well as sand, hence the need to develop alternative solutions by using port dredging sand, which is evaluated by thousands of tons by its use in the concrete that forms the blocks of quay walls. After having demonstrated in a previous work the possibility of using the dredged sand from the port of Agadir in concrete formulations, the present work consists to show the possibility of using the dredged sand from the port of Agadir in concrete formulations that can be used in the construction of quay wall blocks, by studying the stability of a quay wall at −18 mZH made from concrete blocks derived from a concrete formulation based on the dredged sand, more specifically 50% of the sand used in the formulation is a dredging sand extracted from the port of Agadir, the quay wall stability study will consist of a deep analytical and detailed study of the sliding stability, the overturning and the bearing capacity of the foundation, taking into account the different calculation limit states, the structure of the quay wall studied is the quay wall of the port of Tangier Med II located in the north of Morocco. The eventual use of dredged sand in the concrete of the quay wall will provide enormous gains in the quantities of sand and therefore allow less consumption of construction materials, and will also play a more important role in the preservation of the marine environment by avoiding the dumping of dredged materials, which has a negative impact on the marine fauna and flora.

A greater understanding of ozone damage to the environment and health led to an increased demand for accurate predictions. This study provides two new accurate hybrid models of ozone prediction. The first one (CHIMERE-NARX) is based on a NARX model as a post-processing of the CHIMERE model. In the second (CHIMERE-NARX-DWT), a discrete wavelet transform (DWT) has been added. Our models were built and validated using ozone measurements from the Mediouna station in Casablanca, Morocco, from February 1

Air quality is a complex issue which depends mutually on source emission, land topography, meteorological parameters and used mathematical tools for forecasting its dispersion. One of major toxic gas is ozone which could be dangerous to human health. The present work has been developed to forecast ozone concentrations in the city of Agadir using a Recurrent Neural Network (RNN). Predicting ozone concentrations will provide useful information, especially, for decision makers in order to prevent and reduce the ozone human health impacts. The data was collected in the most polluted area in the city using a mobile monitoring station during a period of 60 days. We have tested different neural network architectures and we found that the 1-hour forecast model, whose input parameters are a combination of meteorological parameters as well as CO and SO\(_2\), give the most optimal results. Coefficient of Correlation (CC), Root Mean Square Error (RMSE) and Mean Absolute Error (MAE) were used to evaluate the statistical agreement between observed and predicted values. The model successfully predicts the ozone concentration by a bias of 4 \(\mu\)g.m\(^{-3}\) over 24 hours and which a correlation coefficient is more than 80%. This work highlights the ability of the recurrent neural networks to forecast air pollutant concentrations in urban areas.

The growth of infrastructure has automatically led to a decrease in the deposits of concrete constituents since concrete is considered the world’s leading construction material. This is why it is necessary to move towards the development of alternative solutions, in particular the replacement of sand by dredged port sediments, which are assessed by thousands of tonnes of products considered as waste, the dredging of these products impacts the ecological system and negatively influences the marine environment. Through this article, we will study the possibility of requalifying the dredging sand of the port of Agadir in Morocco considered as waste through its use in concrete formulations by examining its behaviour with a sea-set cement and a 3rd generation admixture.

The knowledge of the mechanical parameters of the materials is important for characterization of new structures. In this context, our work is devoted to the development of a new inverse approach, which consists of identifying the mechanical parameters of a linear coaxial constitutive law material, based on the force-displacement pairs obtained by the finite element method. Indeed, we have translated this inverse problem, on the one hand, into a problem of minimization of a functional by the conjugate gradient method. On the other hand, into a problem of optimization by means of the Karush-Kuhn-Tucker optimality conditions. Finally, we illustrate the study with some numerical examples.

The degraded outdoor air quality in Morocco has become for decision makers a topic of major concern. However, taking into account the purchase and maintenance costs for monitoring network, air quality modeling is a primordial tool to predict the air quality evolution scenarios all over the Moroccan territory. Accordingly, a first air quality modeling based on CHIMERE/WRF was for the first time implemented and tested within Agadir-City. The present study allowed obtaining preliminary spatial distribution mapping of 5 relevant pollutants concentration all over the city. Furthermore, model evaluations were compared to available data from ground-based monitoring station installed within Agadir City.

Ozone concentration generally affects a health system, including human health, and an ecosystem, including plant properties and soil processes. Based on high-performance computing, this study used the transport chemistry model CHIMERE to model ozone pollution in the city of Agadir. The aim is to investigate the integrating horizontal and vertical transport effect on ozone concentration and computation time. The findings are validated experimentally by measurements and also compared with other studies. The results highlighted four main points: First, the CHIMERE ozone modeling remains acceptable with a correlation coefficient of 70%. Second, the combination Adv00 based on the Upwind method gives good results in terms of ozone concentration with a significant implementation time, equivalent to 80 minutes for 360 hours of prediction, which means an optimization in computational performance. Third, it is required to optimize all possible parts of the modeling process to reduce costs and time. Fourth, detailed local emission information is recommended to get a clearer picture of the correction of the CHIMERE output. The present work can serve as guidance for the CHIMERE settings in the case of limited computational infrastructure for long-term studies and studies using a high spatial resolution to predict polluted air.

International audience; A detailed investigation of the physicochemical properties and thermal characteristics of argan fruit residues (AFRs) was carried out to identify their potential application as biofuels. This experimental study covered the four main by-products of argan fruit: argan pulp (AP), argan nut shell (ANS), argan oilcake (AOC) and argan deoiled cake (ADC). Physicochemical analysis was performed to characterize biomass-based materials. Thermogravimetric techniques (TG, DTG and DTA) were applied to assess structural decomposition, biomass reactivity and combustion parameters. Lastly, thermal conductivity and diffusivity between 25 and 100 °C were measured using the transient plane source technique (TPS). The study shows that heating values were in the range of 17–22.5 MJ kg−1, which is comparable to those of wood pellets and lignite coal. The maximum ash content was found in AP and the minimum in ANS. The residual oil of AOC was found to affect the drying process and calorific value. Thermal analysis showed that ANS has the highest ignition temperature and thermal conductivity values and therefore appears to be the most reactive material. Our data show that ANS has a good potential to produce heat through direct combustion. A pretreatment appears to be necessary to improve the characteristics of AP and AOC in order to make them suitable biofuels in the near future.

International audience; Argan shell is one of the main by-products during argan oil production. It is considered as an attractive, cheap and renewable biomass source for sustainable energy utilization. The present paper reports on combustion characteristics of argan shell in order to evaluate their potential for thermochemical conversion. Combustion studies using thermogravimetry (TG) are performed at four different heating rates of 5, 10, 15 and 20 degrees C.min(-1). Kinetic parameters under non-isothermal condition are calculated using FWO (Flynn-Wall-Ozawa method) and KAS (Kissinger-Akahira-Sunose) model free methods. From the results obtained, it was revealed that when the conversion level (alpha) fluctuates between 0.1 and 0.55, the average activation energy were 154 and 145 KJ/mol for FWO and KAS methods, respectively. Then, it decreases drastically with alpha >= 0.6, reflecting the kinetic complexity of the combustion process characterized by a faster reaction caused by the intense devolatilization stage. Overall, the results highlight the potential use of argan shell as a biomass product for thermal conversion through combustion.

Combustion analysis of fixed beds of argan nut shell (ANS) biomass was studied experimentally, for the purpose of testing the potential application of local waste, as direct biofuel for thermal conversion. Particular consideration was given to the influence of air flow rate and fuel particle size on combustion temperature, burning rate, and pollutant emission evolutions. A comparison was performed with wood pellets (WP) which conform to DinPlus standard. The results showed that the combustion process was dominated by flaming mode. The increase of air flow rate leads to the increase of combustion temperature, fuel burn rate (FBR) and decrease of carbon monoxide (CO) and sulfur dioxide (SO 2 ) concentrations until a moderate value (1585 kg m−2 h−1), Note that the SO 2 emissions are mainly coming from combustion of the nourishing tissue of argan almonds. The emissions of nitrogen oxides (NO x ) are below 100 ppm (corrected at 10% oxygen) for all experiments. Broken particles induce a higher FBR compared to raw ANS and WP. In this case of particle size, combustion temperature and gas emission values were improved with the highest air flow rate (2642 kg m−2 h−1). This leads to the conclusion that broken raw ANS can reach better combustion performances if the required compromise of mixing air and biomass was achieved. The outcomes from the present research can contribute to optimize the ANS burning in small-scale furnaces.

This article reports on the effect of swirl intensity on the flow and combustion characteristics of pulverized olive waste (OW) burning. Numerical simulations are carried out using the computationa...

International audience; This paper presents an experimental study of argan nut shell (ANS) combustion in a lab-scale furnace. Biomass composition, properties and microstructures were determined. Combustion behaviour, fuel burn rate (FBR), pollutants (CO and NOx), modified combustion efficiency (MCE) and ash analysis were investigated. A comparison with wood pellets (WP) complying with the ENplus Standard was performed. The impacts of air flow rate and particle sizes on the combustion characteristics were analysed and discussed using three average ANS particle lengths: 5-8 mm, 10-18 mm and 25-30 mm. The results show that the smallest length of ANS particles induced a higher FBR and a regular distribution of the flame shapes compared to the other sizes and to wood pellets. Furthermore, the combustion temperatures, CO emission and MCE values were improved with the highest air flow rate used. CO emission was strongly affected by the operating conditions while NOx was very low for all selected cases. Elemental ash composition reveals that no ash agglomeration was observed during experiments in terms of alkali index. Moreover, the obtained ash was in the form of powder instead of agglomerated particles. This experimental investigation improves the understanding of the operational characteristics and the combustion effect of ANS biomass.

Port structures (quays and dykes) need an enormous consumption of materials, in particular concrete and its components, as well as sand, hence the need to develop alternative solutions using port dredging sand, estimated at thousands of tonnes through its use in the concrete that forms the blocks of the quay walls. After having demonstrated in a previous work the possibility of using the dredged sand from the port of Agadir in concrete formulations, the present work consists in showing the possibility of using the dredged sand from the port of Agadir in concrete formulations that can be used in the construction of concrete tetrapods from a concrete formulation based on dredged sand, more precisely 50% of the sand entering in the formulation is dredged sand extracted from the port of Agadir. The eventual use of dredged sand in the concrete of the tetrapods will lead to enormous gains in the quantities of sand and thus to a lower consumption of construction materials, and will also play a more important role in the preservation of the marine environment by avoiding the trapping of the dredged materials.

This article presents the effect of inlet swirl motion on the flow behavior and combustion dynamics of pulverized olive cake (OC) in a 3D vertical furnace. The spherical OC particles are injected p...

Generalized Standard Materials are governed by maximal cyclically monotone operators and modelled by convex potentials. Gery de Saxce’s Implicit Standard Materials are modelled by biconvex bipotentials. Analyzing the intermediate class of n-monotone materials governed by maximal n-monotone operators and modelled by Fitzpatrick’s functions, we find out that n-monotonicity is a relevant criterion for the materials characterisation and classification. Additionally, the Fitzpatrick’s functions allow to describe the thermal or mechanical equilibrium equations of n-monotone materials by primal–dual two-fields variational principles. In doing so, we are led to Dirichlet–Neumann problems that we solve by Uzawa-type algorithms.

aim of this work is to identify the tensor of thermal conductivity and volumetric heat of an anisotropic material with conductivity tensor diagonal, the heat conduction follows the linear Fourier law. The temperature field in the plate is obtained by solving the analytical heat equation. The solution of the direct problem is simulated by applying the Finite Element Method 2D. The inverse problem is solved by returning the intermediate step of the MEF. An optimization method based on conjugate gradient algorithm has enabled us to develop an identification of thermophysical parameters procedure.

The aim of this work is to lay the groundwork for identifying digital mechanical parameters of materials with elastic. Most of the tests do not allow identifying these parameters automatically. The use of the finite elements of calculations for sizing works is thus limited by a poor understanding of the mechanical properties. In this context, it raises the issue of inverse analysis [1] [2]. From this information about the parameters of the laws of material behavior, is it possible to obtain the displacement field from in situ measurements and how does digital technology obtain a determination of these parameters accurately and systematically? In this work we present a new approach by providing a formulation is easily used by treating the inverse problem. It is based on the finite element method, which, in a direct problem, gives the displacement field knowing the mechanical properties and an inverse problem gives the mechanical knowledge of the field trips. The resolution of the direct problem has yielded results. The latter is in agreement with the simulation code of commercial calculation. This allowed us to address the inverse problem with no understanding by offering an alternative identification using a database previously determined [3].

We consider a material whose stress–strain relation is linear but not symmetrical. As the research of a potential is futile, we attempt to represent the constitutive law by a bipotential. Fitzpatrick method leads us to construct a suitable increasing sequence of bipotentials. The technique is exemplified on coaxial constitutive laws.

The aim of our study is to develop an approach to both experimental and numerical modeling to the thermal behavior of a material by identifying these thermal parameters. The theoretical part is based on the finite element method which is a starting point to solve a two-dimensional inverse heat. The experimental measurements are performed by infrared thermography. All these experimental and numerical techniques give this method properties valued in the industrial world as the non-intrusive measurements and real-time calculations. For this, we have supported a system of equations and the temperature field, so before starting the inverse problem, we addressed the direct problem by finite element method that has been compared to measures experimental infrared thermography well to check the validity of equations, so it’s the purpose of this work.

International audience; Let A be a 3D symmetric elasticity tensor not necessary isotropic. If µ is an invariant measure on SO(3), then µ is a convex combinaison of the Haar measure. The nearest isotropic elasticity tensor is obtained by integrating the tensor A on the rotation group SO(3). For the numerical approach, we integrate the elasticity tensor on the unit ordinary ball B(0,1).

Influence of material parameters on the forming limits of sheet metals. The forming limits in biaxially stretched sheets are analysed by using a Marciniak-Kuczynski localization approach with a new plane-stress yield criterion. The limits to ductility depend on the strain-hardening capacity and the strain-rate sensitivity of the material. In biaxially stretched sheets, an additional material parameter that controls the forming limits is the yield locus curvature. The effect to the material parameters is analysed with particular attention to the yield surface shape on the forming limits diagrams.

The velocity of a semi-infinite crack slowly propagating in aninfinitely long strip made of a viscoelastic composite material isdetermined according to Christensen's fracture criterion. The edges ofthe strip are subjected to uniform opposite displacements normal to thecrack plane. The crack velocity is obtained from an energy balanceequation involving the energy dissipated in the whole strip; the latteris evaluated using an approximate, but sufficiently accurate, expressionof the stress field in the structure obtained by taking into account thestrong anisotropy of the long fibre composite material of interest. Thisnew version of Christensen's criterion compares favourably with theoriginal one and gives crack velocity predictions very close to thoseprovided by Schapery's criterion.

Generalized Standard Materials are governed by maximal cyclically monotone operators and modeled by convex potentials. Gery de Saxce’s Implicit Standard Materials are modeled by biconvex bipotentials. We analyze the intermediate class of n-monotone materials governed by maximal n-monotone operators and modeled by Fitzpatrick’s functions. Revisiting the model of elastic materials initiated by Robert Hooke, and insisting on the linearity, coaxiality and monotonicity properties of the constitutive law, we illustrate that Fitzpatrick’s representation of n-monotone operators coming from convex analysis provides a constructive method to discover the best bipotential modeling a n-monotone material. Giving up the symmetry of the linear constitutive laws, we find out that n-monotonicity is a relevant criterion for the materials characterization and classification.