Publications Scientifiques
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Item Optimisation methods applied to the distribution of rotor blades in a turbofan engine(Society for Structural Integrity and Life (DIVK), 2025) Houari, Amin; Amrouone, Salah; Madani, Kouider; Bendine, Kouider; Lecheb, Samir; Saada, KhalissaThe primary aim of this research is to enhance the distribution of rotor blades in a turbofan engine to achieve superior static balancing. To this end, an advanced optimisation method is proposed to ensure that the mass imbalance correction stays within the allowed tolerance limits, even after the rotor blades' positions are altered during maintenance activities. This proposed method leverages a genetic algorithm that is refined through the integration of various optimisation techniques. The use of MATLAB® code plays a crucial role in this process, providing the computational power and flexibility needed to implement and test the optimisation algorithm effectively. In practical terms, the method involves adjusting the positions of the rotor blades to minimise the static imbalance, which can significantly impact the performance and longevity of the engine. By maintaining the mass correction within specified tolerances, the engine can operate more smoothly and efficiently, reducing wear and tear and potentially extending its operational lifespan. The integration of MATLAB® allows for precise calculations and simulations, ensuring that the proposed adjustments are both feasible and effective in real-world scenarios. This approach not only improves the immediate balance of the rotor but also ensures that the balance is maintained over time, even with the positional changes that occur during routine maintenanceItem Damage crack growth detection of composite pipeline using NDT(Université M'Hamed Bougara Boumerdes : Faculté de Technologie : Département Génie Mécanique, 2021) Brihmat, Chahira; Lecheb, Samir; Chellil, A.; Safi, B.; Kebir, H.; Mechakra, H.; Tablit, B.Item Failure Prediction of Laminated Composites: Simulation of the Nonlinear Behavior and Progressive Damage(Korean Fiber Society, 2023) Bensalem, Abdelhafid; Daoui, Abdelhakim; Cheriet, Abderrahmane; Lecheb, Samir; Chellil, Ahmed; Kebir, Hocine; Aissani, LindaThe Hashin’s criteria are useful in composite structural applications because of their simple concept and their theoretical results are relatively close to that got in the experimental parts. In the present study, in the present study, the failure of the composite laminates under static loading have been developed predicted using Hashin’s Criterion. Nonhomogeneous stresses within a structure may induce a complicated failure scenario whereby one ply at a point can initiate failure and can affect also other plies at the same point or the same ply in different neighboring points. With neglecting the possibility of interlaminar failure, only in-plane loads are considered in this state. The results showed that the failure analysis was proposed to simulate the nonlinear laminate behavior and progressive damage of selected laminates under to their ultimate strength. In our approach, the finite element analysis is performed using MATLAB software to study the effect of tensile and compressive loading on the failure of epoxy resin laminate AS4/3501-6.Item Damage diagnostic of ball Bearing using vibration analysis(Université M'Hamed Bougara Boumerdes : Faculté de Technologie, 2021) Belaid, Siham; Lecheb, Samir; Chellil, Ahmed; Djellab, Amira; Mechakra, Hamza; Kebir, HocineMaintenance of any machinery is very important in view of downtime of machinery. The bearing sector is one of the examples without which not single rotating machinery work, Our work is devoted first to a study of static behavior by determining the stress, strain and displacement, then dynamic behavior by determining the first four naturals frequencies. Secondly the dynamic analysis of the Bearing with defect as a function of crack size and location. Finally, the analysis of the results obtained in terms of residual parameters, allow us to draw a roadmap for the diagnosis and maintenance of bearings.Item Crack growth diagnostic of ball bearing using vibration analysis(Sciendo, 2022) Belaid, S.; Lecheb, Samir; Chelil, A.; Mechakra, H.; Safi, Brahim; Kebir, H.It is known that supported ball bearings have great effects on the vibrations of the gear transmission system, above in all the presence of local faults as well as the crack growths. For this purpose, this paper focuses on shock and vibration crack growth diagnostic of ball bearing using vibration analysis. Our work is devoted first to a study the static behaviour of the ball bearing by determining the stress, strain and displacement, then its dynamic behaviour by determining the first four natural frequencies. Secondly, a dynamic analysis study of the bearing was carried with defects as a function of crack size and location. The obtained results clearly show that the natural frequencies decrease in a non-linear way with the growth of the length of the crack, on the other hand the stress increases with the presence of the singular points of the crack. Finally, this residual decrease in natural frequencies can be used as an indicator of the state of failure, as well as a parameter used for the diagnosis and screening, and to highlight the fatigue life of the bearingItem Correction : Investigating the efect of process parameters for fused flament fabrication(Springer, 2023) Boumedine, Asma; Lecheb, Samir; Benfriha, Khaled; Omnes, PascalItem Identification of vibratory characteristics to the damage of a composite plate(2018) Grabi, Massinissa; Chellil, A.; Lecheb, Samir; Mechakra, H.; Nour, A.; Andrianarison, O.tThe objective of this work is to study the damage behavior of composite structures by examining the influence on fatigue resistance. The finite element model of the plate will allow to analyze the vibratory behavior, to identify the stress, to study the influence of the dynamic loads on the natural frequencies of the plate in bending and torsion and will show the influence of the orientation of the Composite fiber macros on the rigidity of the plate and finally calculate the stability of the plate. The various damage mechanisms associated with these materials will also be presented with particular attention to delamination and cracking. This work will then focus on different technologies to improve the mechanical properties of these composite materials.Item Impact of the fuselage damping characteristics and the blade rigidity on the stability of helicopter(Elsevier, 2013) Chellil, Ahmed; Nour, Abdelkader; Lecheb, Samir; Kebir, H.; Chevalie, Y.Item Dynamic prediction fatigue life of composite wind turbine blade(Techno Press, 2015) Lecheb, Samir; Nour, Abdelkader; Chellil, Ahmed; Mechakra, Hamza; Ghanem, Hicham; Kebir, HocineItem Mechanical characterizations of composite material with short Alfa fibers reinforcement(Elsevier, 2015) Mechakra, Hamza; Nour, Abdelkader; Lecheb, Samir; Chellil, Ahmed