29 research outputs found
Numerical study of wind-tunnel wall effects on lift and drag characteristics of NACA 0012 airfoil
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- shear stress transport (SST-Kω). 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
Effect of oil mass flow rate on temperature profile in oil wells
In several design calculations including the development of programs to optimize production, engineers and scientists require accurate prediction of temperature drop due to flow in oil wells. The purpose of this research is to create mathematical models to predict the effect of oil mass flow rate on temperature distribution in oil wells. A numerical mathematical model is developed to study the parameters affecting the dynamic and static temperature profiles in oil wells in production and shutting operation. The temperature distribution of the oil from the reservoir to the surface and the temperature distribution in the wall tubing of the oil well and casing, cement sheaths, and surrounding formation is studied. The natural flow of oil wells in Alwahat area located 70 Kilometres south of Marada area east of Libya in the Zaggut field called (6Q1-59) is taken as a study case. In production case, different mass flow rates in winter and summer seasons are studied. The temperature profile in the horizontal direction is estimated at different depths. The Results show that the surface temperature of crude oil increases with the rise in mass flow rate
Comparison of high-order accurate schemes for solving the nonlinear viscous burgers equation
In this paper, a comparison between higher order schemes has been performed in terms of numerical accuracy. Four finite difference schemes, the explicit fourth-order compact Pade scheme, the implicit fourth-order Pade scheme, flowfield dependent variation (FDV) method and high order compact flowfie ld dependent variation (HOC-FDV) scheme are tes ted. The FDV scheme is used for time disc retization and the fourth-order compact Pade scheme is used for spatial derivatives. The solution procedures consist of a number of tri-diagonal matrix operations and produce an efficient solver. The comparisons are performed using one dimensional nonlinear viscous Burgers equation to demonstrate the accuracy and the convergence characteristics of the high-resolution schemes. The numerical results show that HOC-FDV is highly accurate in comparison with analytical and with other higher order schemes
Ionic Surface Dielectric Properties Distribution on Reservoir Sandstone
The petrophysical and dielectric properties for both carbonate and saturated sandstone with monovalent and divalent electrolyte they are accurately modeling of anisotropic dielectric properties has been the major research area in oil and gas industries for effective sweep efficiency. The reservoir petrophysical properties consist of cation and anion exchange capacity on a specific area and the sandstone porosity. The transportation of the ions is a charge carrier that mediates conduction in the pore fluids under the electrical double layers that exist between the minerals and the pore fluids interface. The dielectric anisotropic and the frequency-dependent behavior of reservoir sandstone with the minerals will be fully elucidated, it was revealed from the result obtained the effect of the anisotropic dielectric properties on the reservoir sandstone based on the influx of NaCl electrolyte modify the wettability of rock formation from oil-wet to water-wet at 9000 and 11000 ppm concentration with the aids of the electromagnetic field. The resistivity index of the reservoir sandstone reduces with the increase of electrolyte to the system
Multidisciplinary Optimization of Axial Turbine Blade Based on CFD Modelling and FEA Analysis
The turbine blade is designed to achieve expansion at high efficiency levels. For improving the turbine efficiency, different aerodynamic design optimisations are performed. On the other hand, the aerodynamic design must be enhanced to match the mechanical design. This research proposes a novel design optimisation method for both aerodynamic and mechanical requirements. A multidisciplinary optimisation approach is used to improve the reliability of the turbine design, which included the use of Computational Fluid Dynamics (CFD) models and Finite Element Analysis (FEA). The primary objective is to guarantee that the aerodynamically optimised blade profile could efficiently withstand mechanical stress. The multidisciplinary optimisation approach is successful in reducing total equivalent pressures from 49.72 MPa to 41.73 MPa while keeping the turbine's overall efficiency at an impressive level of 80.95%. These Results highlight the effectiveness of using a multidisciplinary optimization method to successfully improve the efficiency of a turbine blade profile while simultaneously ensuring its ability to withstand the needed mechanical loads. Using a multidisciplinary optimisation method, the turbine maintains an impressively high efficiency of approximately 83%, with only a marginal reduction of 1.8% compared to the efficiency achieved solely through aerodynamic blade optimisation
Effect of Various Plasticizers in Different Concentrations on Physical, Thermal, Mechanical, and Structural Properties of Wheat Starch-Based Films
: Biocomposite materials are essential for environmental protection, as they have the ability of substituting synthetic plastic with natural materials. This work investigated how different plasticizers (Glycerol (G), Fructose (F), Sorbitol (S), and Urea (U)) affect the morphological, mechanical,
thermal, and physical characteristics of films made of wheat starch at various concentrations (0%, 15%, 25%, and 35%). Plasticizers were added to improve the flexibility and homogeneity of the wheat starch-based bioplastic. Control film exhibited high tensile strength (38.7 MPa) with low elongation (1.9%). However, films plasticized with 35% sorbitol showed the highest elongation, which was 60.7% at break. At 35% of all plasticizers, fructose showed the highest tensile strength, with 7.6 MPa. The addition of different plasticizers shows improvement in water resistance; films plasticized
with glycerol had the lowest water absorption at 35% fructose (187.4%) and also showed coherent surfaces. Glycerol, sorbitol, and urea films showed a higher mass loss compared to fructose films. Fructose showed the highest performance after the analysis of the results, with low water absorption, water content, and mass loss and with high mechanical performance at 35% of fructose. SEM images show that the addition of fructose and glycerol improves the surface homogenate, while sorbitol and urea have a less compact structure with large pores
Comparison of 2D and 3D modelling applied to single phase flow of nanofluid through corrugated channels
Nanofluid flow through non-corrugated and corrugated channels is studied using a
two-dimensional (2D) and three dimensions (3D) numerical simplification. Due to the
high computational costs of a full 3D grid model, the 2D approach offer a more practical
advantage. However, little information about its validity is available. The aim of this
study is to explore to which extent 2D simulations can describe the flow within a 3D
geometry, and to investigate how effective the commonly used 2D numerical
simplification is in nanofluid flow through non-corrugated and corrugated channels. A
case study has implemented with 2D and 3D mesh models to compare their results
taking into consideration the analysis of heat transfer and pressure drop. A simulation
has been carried out using Ansys fluent software to compare the results for different
Reynolds Numbers ranges from 10000 to 30000 and different geometries non�corrugated, semicircle and rectangular channels. The results show that for non�corrugated channel there is a slight difference between 2D and 3D results for all
Reynolds number ranges, while for both semicircle and rectangular corrugated
channels, the difference becomes larger for high Reynold’s Number
Assessment of Recycled Plastic Performance in The City of Zawia Libya
Plastic particles and other plastic pollutants exist in our environment and in the food chain and threaten human health. Inappropriate handling and disposal of plastic waste is a global problem and is still not resolved in many countries. When recycling companies need to deal with complex plastic, the problem becomes even more serious, which can prevent their recycling initiatives. The main purpose of this research is to determine whether recycled products can be used as post-consumer materials in various recycling ratios to produce new products without reducing quality. In the study, 0 percent, 20%, 50%, 70%, and 100 percent regrind ratios were used. Reduction, hardness, and solid density are the qualities studied. The results show that the properties did not change significantly
Assessment of Recycled Plastic Performance in The City of Zawia Libya
Plastic particles and other plastic pollutants exist in our environment and in the food chain and threaten human health. Inappropriate handling and disposal of plastic waste is a global problem and is still not resolved in many countries. When recycling companies need to deal with complex plastic, the problem becomes even more serious, which can prevent their recycling initiatives. The main purpose of this research is to determine whether recycled products can be used as post-consumer materials in various recycling ratios to produce new products without reducing quality. In the study, 0 percent, 20%, 50%, 70%, and 100 percent regrind ratios were used. Reduction, hardness, and solid density are the qualities studied. The results show that the properties did not change significantly