ABDELKADER Djerad

Chenene Nadia

Etude numdrique d'une convection forcd en2D Par la mdthode de volumes finis.

Salmi Soumia

Etude numerique d'une convection naturelle en 2D Par la mdthode de volumes finis.

parameter estimation of Compound-Gaussian with lognormal texture (CG-LNT) distribution is considered. The CG-LNT distribution is nonGaussian heavy-tailed distribution, it used in radar domain to describe the variation of high-resolution sea clutter. The probability density function (PDF) is characterized by two parameters, the standard deviation and the mean. This paper proposes a closed form estimator of CG-LNT distribution parameters based on fractional negative order moment (FNOME). Comparative study is established against the existing estimators existing in the literature to evaluate the efficiency of the proposed estimator using CG-LNT simulated and real sea clutter data, the mean square error (MSE) criterion is also used to measure the estimation accuracy.

Citation

zoulikha douiou , IZZEDDINE Chalabi , ABDELKADER Djerad , , (2024-07-09), Fractional Negative Order Moment Parameter Estimator of Compound-Gaussian Clutter with Lognormal Texture, PRZEGLĄD ELEKTROTECHNICZNY, Vol:100, Issue:7, pages:42-45, SEP – Polish Electrical Engineers Association (SEP)

In the atmospheric boundary layer, the uniform and unidirectional wind speed does not seem to be valid; it has a logarithmic or exponential profile. Close to the ground, this speed is slowed down by the roughness of the ground and the presence of obstacles, while going uphill, the wind speed becomes more and more important and reaches a determined value. For the power produced by the wind turbine in the atmospheric boundary layer, the moment of force exerted by the wind is not the same over the entire rotor actuator disc. In this context and to remedy this problem, we present in this work a method which aims to calculate the power developed by a wind turbine where the wind speed is not constant in the atmospheric boundary layer. This method is based on the discretization of the rotor actuator disc into elementary surfaces, using the power characteristic curve which corresponds to given wind speeds of such a wind turbine. By a computer program developed, the elementary power is calculated in each element of discretized surface, then, the total power of the wind turbine in atmospheric boundary layer is only the sum of the elementary powers. To show the validity of this method, the results obtained in this study are analyzed and discussed. It should be noted that the power in each discretized surface element is different from that of the others, because the wind speed is different at each height

Citation

SAID Zergane , ABDELKADER Djerad , seyf-eddine.guesmia@mail.concordia.ca, ,(2022), The developped power of a wind turbine in the boundary layer,International Seminar on Industrial, Engineering and Applied Mathematics,Skikda, Algeria

The aim of this work is to prove the well-posedness of some linear and nonlinear mixed problems with integral conditions defined only on two parts of the considered boundary. First, we establish for the associated linear problem a priori estimate and prove that the range of the operator generated by the considered problem is dense using a functional analysis method. Then by applying an iterative process based on the obtained results for the linear problem, we establish the existence, uniqueness and continuous dependence of the weak solution of the nonlinear problem.

Citation

ABDELKADER Djerad , , (2021), On a Nonlinear Mixed Problem for a Parabolic Equation with a Nonlocal Condition, axioms, Vol:10, Issue:2021, pages:19, mdpi

The aim of this work is to prove the well posedness of some posed linear and nonlinear mixed problems with integral conditions. First, an a priori estimate is established for the associated linear problem and the density of the operator range generated by the considered problem is proved by using the functional analysis method. Subsequently, by applying an iterative process based on the obtained results for the linear problem, the existence, uniqueness of the weak solution of the nonlinear problems is established.

Citation

ABDELKADER Djerad , , (2021), Well posedness of a nonlinear mixed problem for a parabolic equation with integral condition, Boundary Value Problems, Vol:70, Issue:2021, pages:24, springer

The aim of this work is to prove the well posedness (i.e: existence, uniquenessand the contin- uous dependence on the initial conditions) of some posed linear andnonlinear mixed problems with integral conditions. First, an a priori estimate isestablished for the associated linear problem and the density of the operator rangegenerated by the considered problem is proved by using the functional analysismethod. Subsequently, by applying an iterative process based on the obtainedresults for the linear problem, the existence, uniqueness of the weak solution of thenonlinear problems is established.

Citation

ABDELKADER Djerad , ,(2021), Tempered generalized functions type,Second National Mathematics Seminar,University of Constantine

Nowadays, fault detection in induction motors has gained importance. Motor health monitoring is performed to diagnose their operating condition using vibration signals. These signals are processed using different signal processing methods to extract the characteristic parameters permitting localization of the fault. In this paper, we propose a diagnostic method based on Hilbert and Discrete Wavelet Transforms for the detection of bearing faults in asynchronous machines. The discrete wavelet transform (DWT) is intended to provide the detail coefficients while the Hilbert transform (HT) is used to obtain the temporal envelope then the envelope spectrum of the detail. The kurtosis value indicates the optimum decomposition wavelet level containing the significant frequencies corresponding to faults for early detection. The result obtained by HT-DWT is more suitable for the analysis of emergency signals. This technique is effective for either stationary or non-stationary signals. Healthy case is compared to faulty case in order to extract frequencies characterizing different faults. The validation of this approach is evaluated by comparing theoretical with experimental results.

Citation

ABDELKADER Djerad , ,(2021), Vibration Signal Analysis for Bearing Fault Diagnostic of Asynchronous Motor using The Discrete Wavelet Transform Technique,IC-SEAM’21,University of Ouergla

The main objective of this work is the analysis and the modeling of the wind by all the characteristics in order to predict the variations of the intensity of its annual average speed in the atmospheric boundary layer during a year using 'a new method based on artificial neurons. By introducing data and cumulative wind speed measurements over several decades from such a windy site, this method, developed on MATLAB, makes it possible to estimate the annual wind speed at 5 m from the ground in the years to come. The simulation results obtained in this work are analyzed and validated by comparing them with the results measured on this site in the years preceding the measurement period.

Citation

SAID Zergane , ABDELKADER Djerad , MANSOUR Rokbi , ,(2021), Prediction of the variation of wind speed by a method based on artificial neurons network,The Sixth International conference on machanical and energy-ICME'2021',Sousse, Tunisia

Combustion chambers are used in energy systems mainly to increase heat transfer. In this paper, a modern design procedure of a combustion chamber of a boiler is presented, in order to improve temperature distribution over the combustion chamber borders, as well as the combustion dynamics such as interior pressure and combustion velocity. The design process is mainly based on changing the geometric aspects of the combustion chamber, more particularly the geometry of the bottom side. Thus, a simulation study using Fluent Software has been carried out on two main geometries, namely: a cylindrical combustion chamber with a flat bottom and another one with a convex bottom respectively. The simulation results have shown remarkable improvements in the combustion chamber in case of convex bottom behavior in terms of temperature distribution and heat transfer and therefore the good efficiency of the boiler

Citation

ABDELKADER Djerad , , (2019), Comparative Numerical Simulation in a 2D Combustion Chamber, Based on the Finite Volume Method, International Review of Mechanical Engineering, Vol:13, Issue:6, pages:340-349, Scopus

Pour qu’une chaudière soit compétitive elle doit, au risque de formuler une lapalissade, coûter le moins cher possible tout en assurant le service exigé. Réduire les coûts doit se faire à toutes les étapes de la conception de la chaudière. L’intérieur de la chaudière est différent suivant l’architecture présente par le constructeur, La construction de la chambre de combustion d’une chaudière en acier reste jusqu'à nos jours basée sur l’expérience pratique des hommes de métier. Afin de retrouver le meilleur scenario qui nous permet de mieux profiter de l’énergie de combustion, on a réalisé une étude numérique sur un jet coaxiaux de méthane-air par un bruleur a air soufflée fixée a l’axe symétrique de la chambre de combustion du chaudière en acier model CH01 de la société ECOCHAUDIERE pour répondre a des questions poser par le service technique concernons des déformations a le fond de foyer et le rendement de la chaudière. La résolution numérique du problème est réalisée a l’aide de code Ansys (Fluent), en utilisant les modèles de turbulence k-ɛ standard, de combustion « Eddy Dissipation », qui utilise la méthode des volumes finis pour la résolution des équations aux dérivées partielles.

Citation

ABDELKADERDjerad , ,(2019); Etude Numérique d’un Ecoulement Réactif en 3D par la Méthode des Volumes Finis,university Ferhat Abbas SETIF1,

For a boiler must be competitive at the risk of making the obvious, be as inexpensive as possible while ensuring the required service. Reduce costs should be at all stages of the design of the boiler. The construction of the combustion chamber of a steel boiler remains to this day based on the practical experience of tradesmen. In order to find the best scenario that allows us to enjoy the energy of combustion and recovery and minimize risk deterioration of the devices used, In this case our main goal is to find the techniques to increase the heating surface - and therefore the power of the boiler - to the furnace hearth with small changes in the existing boiler materials on geometry or shape without making Increase either the cost or the area of the boiler for which remainder of the same size but with a higher power and a higher yield; In a first study we concentrate on the bottom of the combustor of the steel boiler, which is a cylinder with one end open and the other closed by the bottom of the hearth; This bottom is flat in the existing model, it has been changed with a convex bottom of the same material (refractory steel); The temperature was measured on the focal point and on the bottom; The experimental results give an increase in temperatures over almost the entire heating surface also on the convex bottom; This increase in temperature gives important results; Also for the pressure and the velocity in the hearth so we found a powerful boiler with the same conditions and the same materials; Which also prove by a comparative numerical study on the two cases in two dimensions; To justify numerical results and also verify the increase in temperatures digitally; And validate the experimental results with the numerical results; this numerical study was conducted on a coaxial jet by a methane-air burner model Max 120 Ecoflam (Italy) for air blown attached to the symmetrical axis of the combustion chamber of the steel boiler model CH01 of company SARL ECOCHAUDIERE (Algeria) answer questions put by the technical service concernons deformation was home to bottom and the efficiency of the boiler. The numerical solution of the problem is realized with the help of Ansys commercial code (Fluent), using turbulence models k-ɛ standard combustion "Eddy Dissipation". We examine the effect of the change in the form of the bottom end of the combustion chamber, dynamics and thermal structure of the flow and efficiency of the boiler.

Citation

ABDELKADER Djerad , , (2017), Numerical Study of Turbulent Flow in Two Dimensions by the Finite Volume Method, Transylvanian Review, Vol:25, Issue:14, pages:3909-3924, Thomson Reuters