Mostafa Essuri - Academia.edu (original) (raw)

Papers by Mostafa Essuri

Research paper thumbnail of Aerodynamic characteristics of low Reynolds number airfoils

Tehnicki Vjesnik-technical Gazette, Feb 1, 2017

Original scientific paper Assessment of airfoil aerodynamic characteristics is essential part of ... more Original scientific paper Assessment of airfoil aerodynamic characteristics is essential part of any optimal airfoil design procedure. This paper illustrates rapid and efficient method for determination of aerodynamic characteristics of an airfoil, which is based on viscous-inviscid interaction. Inviscid flow is solved by conformal mapping, while viscous effects are determined by solving integral boundary layer equations. Displacement thickness is iteratively added to the airfoil contour by alternating inviscid and viscous solutions. With this approach efficient method is developed for airfoil design by shape perturbations. The procedure is implemented in computer code, and calculation results are compared with results of XFOIL calculations and with experiment. Eppler E387 low Reynolds number airfoil and soft stall S8036 airfoil are used for verification of developed procedure for Reynolds numbers 200000, 350000, and 500000. Calculated drag polars are presented in this paper and good agreement with experiment is achieved as long as small separation is maintained. Calculated positions of laminar separation, reattachment, and turbulent separation closely follow experimental measurement. The calculations are performed in relatively short time, which makes this approach suitable for low Reynolds number airfoil design.

Research paper thumbnail of Numerical Study of Wind-Tunnel Wall Effects on Lift and Drag Characteristics of NACA 0012 Airfoil

CFD Letters, 2020

Possible interference effects of the wind tunnel walls play an important role especially for meas... more Possible interference effects of the wind tunnel walls play an important role especially for measurements in closed-wall test sections. In this study, a numerical analysis of two-dimensional subsonic flow over a NACA 0012 airfoil at different computational domain heights, angles of attack from 0o to 10o, and operating Reynolds number of 6×106 is presented. The work highlights the role of computational fluid dynamics (CFD) in the investigation of wind tunnel wall effect on lift curve slope correction factor (Ka). The flow solution is obtained using Ansys Fluent software by solving the steady-state continuity and momentum governing equations combined with turbulence model k-v shear stress transport (SST-K?). The numerical results are validated by comparing with the available experimental measurements. Calculations show that the lift curve slope correction results are very close to the published data.

Research paper thumbnail of Effect of Mesh Type on Numerical Computation of Aerodynamic Coefficients of NACA 0012 Airfoil

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2021

Mesh type and quality play a significant role in the accuracy and stability of the numerical comp... more Mesh type and quality play a significant role in the accuracy and stability of the numerical computation. A computational method for two-dimensional subsonic flow over NACA 0012 airfoil at angles of attack from 0o to 10o and operating Reynolds number of 6×106 is presented with structured and unstructured meshes. Steady-state governing equations of continuity and momentum conservation are solved and combined with k-v shear stress transport (SST-omega) turbulence model to obtain the flow. The effect of structured and unstructured mesh types on lift and drag coefficients are illustrated. Calculations are done for constant velocity and a range of angles of attack using Ansys Fluent CFD software. The results are validated through a comparison of the predictions and experimental measurements for the selected airfoil. The calculations showed that the structured mesh results are closer to experimental data for this airfoil and under studied operating conditions.

Research paper thumbnail of Aeroprofili za male Rejnoldsove brojeve

In this thesis, the flow around airfoils at low Reynolds numbers has been modeled. The model util... more In this thesis, the flow around airfoils at low Reynolds numbers has been modeled. The model utilizes inviscid-viscous interaction method. The inviscid-viscous interaction method supplemented by an adequate laminar separation bubble modeling has been proven to be efficient design tool when numerical optimization, by systematic shape modification, is anticipated...У овој тези је моделирано струјање око аеропрофила са ниским Рејнолдсовим бројем. Вискозно невискозна интеракција комбинована са моделирањем ламинарног мехура је ефикасан метод за конструисање нових аеропрофила систематским модификовањем облика аеропрофила. Невискозно решење је засновано на конформном пресликавању. Вискозна формулација је заснована на решавању интегралних једначина за количину кретања и енергије. Када нема одцепљења струјања примењен је Еплеров модел за предвиђање транзиције из ламинарног у турбулентно струјање. Ламинарни мехур, који узрокује отцепљење је моделиран из три сегмента: ламинарни део, турбулентн...

Research paper thumbnail of Finite Element Modeling of Composites System in Aerospace Application

Applied Mechanics and Materials, 2012

The characteristics of composite materials are of high importance to engineering applications; th... more The characteristics of composite materials are of high importance to engineering applications; therefore the increasing use as a substitute for conventional materials, especially in the field of aircraft and space industries. It is a known fact that researchers use finite element programs for the design and analysis of composite structures, use of symmetrical conditions especially in complicated structures, in the modeling and analysis phase of the design, to reduce processing time, memory size required, and simplifying complicated calculations, as well as considering the response of composite structures to different loading conditions to be identical to that of metallic structures. Finite element methods are a popular method used to analyze composite laminate structures. The design of laminated composite structures includes phases that do not exist in the design of traditional metallic structures, for instance, the choice of possible material combinations is huge and the mechanical...

Research paper thumbnail of Developing a Dynamic Model for Unmanned Aerial Vehicle Motion on Ground during Takeoff Phase

Applied Mechanics and Materials, 2012

Modeling of take-off and landing motion for a fixed wing (UAV) is necessary for developing an aut... more Modeling of take-off and landing motion for a fixed wing (UAV) is necessary for developing an automatic take off and landing control system (ATOL). Automatic take off and landing system becomes an important system due to wide spread of unmanned aerial vehicles in different applications ranging from intelligence, surveillance, up to missile firing. Automatic take off and landing system reduces damage to an unmanned aerial vehicle and its payload that may be caused by human pilot errors. Furthermore, training human pilot to a sufficient level of skill and experience for takeoff and landing may take several years and significant cost. A human pilot also may impose additional restrictions for UAV operation especially at night time or dusty desert conditions. Although, ATOL adds complexity to the system, it reduces the long run cost and risk caused by takeoff and landing process, and makes UAV takeoff from different runways and at different atmospheric conditions. A mathematical model fo...

Research paper thumbnail of Aerodynamic characteristics of low Reynolds number airfoils

Tehnicki Vjesnik-technical Gazette, Feb 1, 2017

Original scientific paper Assessment of airfoil aerodynamic characteristics is essential part of ... more Original scientific paper Assessment of airfoil aerodynamic characteristics is essential part of any optimal airfoil design procedure. This paper illustrates rapid and efficient method for determination of aerodynamic characteristics of an airfoil, which is based on viscous-inviscid interaction. Inviscid flow is solved by conformal mapping, while viscous effects are determined by solving integral boundary layer equations. Displacement thickness is iteratively added to the airfoil contour by alternating inviscid and viscous solutions. With this approach efficient method is developed for airfoil design by shape perturbations. The procedure is implemented in computer code, and calculation results are compared with results of XFOIL calculations and with experiment. Eppler E387 low Reynolds number airfoil and soft stall S8036 airfoil are used for verification of developed procedure for Reynolds numbers 200000, 350000, and 500000. Calculated drag polars are presented in this paper and good agreement with experiment is achieved as long as small separation is maintained. Calculated positions of laminar separation, reattachment, and turbulent separation closely follow experimental measurement. The calculations are performed in relatively short time, which makes this approach suitable for low Reynolds number airfoil design.

Research paper thumbnail of Numerical Study of Wind-Tunnel Wall Effects on Lift and Drag Characteristics of NACA 0012 Airfoil

CFD Letters, 2020

Possible interference effects of the wind tunnel walls play an important role especially for meas... more Possible interference effects of the wind tunnel walls play an important role especially for measurements in closed-wall test sections. In this study, a numerical analysis of two-dimensional subsonic flow over a NACA 0012 airfoil at different computational domain heights, angles of attack from 0o to 10o, and operating Reynolds number of 6×106 is presented. The work highlights the role of computational fluid dynamics (CFD) in the investigation of wind tunnel wall effect on lift curve slope correction factor (Ka). The flow solution is obtained using Ansys Fluent software by solving the steady-state continuity and momentum governing equations combined with turbulence model k-v shear stress transport (SST-K?). The numerical results are validated by comparing with the available experimental measurements. Calculations show that the lift curve slope correction results are very close to the published data.

Research paper thumbnail of Effect of Mesh Type on Numerical Computation of Aerodynamic Coefficients of NACA 0012 Airfoil

Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2021

Mesh type and quality play a significant role in the accuracy and stability of the numerical comp... more Mesh type and quality play a significant role in the accuracy and stability of the numerical computation. A computational method for two-dimensional subsonic flow over NACA 0012 airfoil at angles of attack from 0o to 10o and operating Reynolds number of 6×106 is presented with structured and unstructured meshes. Steady-state governing equations of continuity and momentum conservation are solved and combined with k-v shear stress transport (SST-omega) turbulence model to obtain the flow. The effect of structured and unstructured mesh types on lift and drag coefficients are illustrated. Calculations are done for constant velocity and a range of angles of attack using Ansys Fluent CFD software. The results are validated through a comparison of the predictions and experimental measurements for the selected airfoil. The calculations showed that the structured mesh results are closer to experimental data for this airfoil and under studied operating conditions.

Research paper thumbnail of Aeroprofili za male Rejnoldsove brojeve

In this thesis, the flow around airfoils at low Reynolds numbers has been modeled. The model util... more In this thesis, the flow around airfoils at low Reynolds numbers has been modeled. The model utilizes inviscid-viscous interaction method. The inviscid-viscous interaction method supplemented by an adequate laminar separation bubble modeling has been proven to be efficient design tool when numerical optimization, by systematic shape modification, is anticipated...У овој тези је моделирано струјање око аеропрофила са ниским Рејнолдсовим бројем. Вискозно невискозна интеракција комбинована са моделирањем ламинарног мехура је ефикасан метод за конструисање нових аеропрофила систематским модификовањем облика аеропрофила. Невискозно решење је засновано на конформном пресликавању. Вискозна формулација је заснована на решавању интегралних једначина за количину кретања и енергије. Када нема одцепљења струјања примењен је Еплеров модел за предвиђање транзиције из ламинарног у турбулентно струјање. Ламинарни мехур, који узрокује отцепљење је моделиран из три сегмента: ламинарни део, турбулентн...

Research paper thumbnail of Finite Element Modeling of Composites System in Aerospace Application

Applied Mechanics and Materials, 2012

The characteristics of composite materials are of high importance to engineering applications; th... more The characteristics of composite materials are of high importance to engineering applications; therefore the increasing use as a substitute for conventional materials, especially in the field of aircraft and space industries. It is a known fact that researchers use finite element programs for the design and analysis of composite structures, use of symmetrical conditions especially in complicated structures, in the modeling and analysis phase of the design, to reduce processing time, memory size required, and simplifying complicated calculations, as well as considering the response of composite structures to different loading conditions to be identical to that of metallic structures. Finite element methods are a popular method used to analyze composite laminate structures. The design of laminated composite structures includes phases that do not exist in the design of traditional metallic structures, for instance, the choice of possible material combinations is huge and the mechanical...

Research paper thumbnail of Developing a Dynamic Model for Unmanned Aerial Vehicle Motion on Ground during Takeoff Phase

Applied Mechanics and Materials, 2012

Modeling of take-off and landing motion for a fixed wing (UAV) is necessary for developing an aut... more Modeling of take-off and landing motion for a fixed wing (UAV) is necessary for developing an automatic take off and landing control system (ATOL). Automatic take off and landing system becomes an important system due to wide spread of unmanned aerial vehicles in different applications ranging from intelligence, surveillance, up to missile firing. Automatic take off and landing system reduces damage to an unmanned aerial vehicle and its payload that may be caused by human pilot errors. Furthermore, training human pilot to a sufficient level of skill and experience for takeoff and landing may take several years and significant cost. A human pilot also may impose additional restrictions for UAV operation especially at night time or dusty desert conditions. Although, ATOL adds complexity to the system, it reduces the long run cost and risk caused by takeoff and landing process, and makes UAV takeoff from different runways and at different atmospheric conditions. A mathematical model fo...