Papers by Keyword: Fluid Mechanics

Abstract: This paper focuses on the design and construction of the front wing for the FS TUL Racing team's monopost, which competes in Formula Student racing. The aim is to use knowledge of fluid mechanics, structural design, materials, CAD systems and CFD simulations to optimise the aerodynamic properties of the vehicle. The thesis explores the basic principles of aerodynamics and analyses the problems encountered in the design process. It includes testing of carbon fabrics and subsequent selection of the most appropriate material for the application. The research also includes the development and comparison of three wing variants using CFD simulations, with subsequent evaluation of the selected variant in the wind tunnel. The result is the selection of the optimum wing variant that meets the specified performance and safety requirements. This variant is then compared with the CAD model using 3D scanning to verify its accuracy and quality. The work contributes to the advancement of the field of race car aerodynamics and provides valuable insights for future development teams, thus supporting further technology development in motorsport.

Abstract: The development of boundary layer flow problem which is involve of nanofluid for improve thermal efficiency in many applications is gaining momentum as most of base fluid are not very good thermal conductor. The enhancement of thermal conductivity can be improving when the magnetic fields is presented. Also, by using this material may encountered another problem such as separation flow. This research is study about magnetic fields effect on unsteady mixed convection flow on nanofluid past a sphere with heat flux as its boundary condition. This problem will consider its mathematical model where it can help to predict the solution in experimental method. The mathematical method that being used is Keller-box because of its ability to solve non-linear equation. The nanoparticles that being choose are copper and titanium oxide with water as based fluid. There will have three equation which is mass, momentum, and energy equation. All equations are transform into non-similarity ordinary differential equations by using appropriate variables. The effect of magnetic parameter on velocity and temperature profiles as well as skin friction and Nusselt number are studied. The results show that volume fraction affected the heat-transfer rate, and skin friction coefficient. This study also shows that magnetic parameter affected the separation times which is decelerated the flow.

Abstract: In this work, we presented a numerical contribution to numerically evaluate the thermal transfer improvement from forcing a 2D flow of air through a baffled channel. Two complex geometry fins were inserted in the flow field to force recirculation zones to augment mixing and thus, the thermal transfer. The dynamic thermo-energy behavior of air is shown for Re numbers ranging from 12 × 10³ to 32 × 10³. The governing equations, employed to simulate the turbulent forced-convection airflow in the domain under investigation, were solved using the finite volume method, by means of CFD FLUENT, based on the SIMPLEC algorithm. For using the complex geometry fins, the augmentations in Nusselt number and friction factor are in the range of 194.108 - 387.322 % and 476.779 - 2603.667 % over the smooth channel with no fin, respectively. In addition, the use of complex geometry fins with Re = 32 × 10³ gives higher TEF than that with Re = 17,000, 22,000, and 27,000 around 12.072 %, 8.568 %, 5.189 %, and 2.389 %, respectively.

Abstract: The interfacial dynamics of a water droplet subjected to SAW (surface acoustic wave) was investigated using a high-speed video camera analysis system. The SAW device was fabricated to generate high frequency vibration for the droplet excitation. The water droplet showed bursting into a fine spray of smaller droplets and ultra-fine mist at the higher applied voltage to the SAW device. The appearance of droplet interface varied with elapsed time of surface acoustic wave excitation. At the initial stage after SAW excitation, capillary surface waves were observed on the droplet interface. Subsequently, surface disintegration due to fine spray and mist ejection was observed. The details of surface response of water droplet on the SAW device were revealed experimentally.

Abstract: Fluid mechanics is the mechanics of fluids, concerned with the motion of fluids and the forces associated with that motion. A Process is a series of operations which produce a physical or chemical change or biotransformation in the nature of a material. Process industries are those industries in which processes have been taken placed. Process engineering stems from chemical engineering, having much wider ranges and much deep content, and focusing on the design, operation and maintenance of process in process industries. Process fluid mechanics may be interpreted as the fluid mechanics related to process industries and/or process engineering, or as the fluid mechanics used for the process industries or process engineering, or as the knowledge of fluid mechanics should be mastered by the process engineers and process researchers or process scientists. Process fluid mechanics can be divided into physical process fluid mechanics, chemical process fluid mechanics, and biological process fluid mechanics.

Abstract: In all process based in powder and in particular in the rotational moulding process, the major physical phenomenon during the flow of the powders is the sintering and grains growth. The sintering is the formation of only one particle starting from two or many particles under the effect of the temperature and the forces of surface tension. We interest in this study in particular at the mechanism of Polyvinylidene fluoride (PVDF) sintering. The results of this study can enable us to maximize our knowledge about sintering mechanism and enable us to determine parameters such as the speed of sintering for the optimization of the process.

Abstract: This paper focused on groundwater flow in certain a tunnel site under conditions of high ground stress and high water pressure (referred to as “two high conditions”). Three-dimensional conceptual model was established for groundwater flow in porous strata with argillation weak permeable media in a long deep buried tunnel site. Groundwater flow field was studied by means of three-dimensional numerical simulation. Results show that there is good agreement between numerical simulated and observed groundwater table and that the conceptual model and the numerical simulation are reliable. Prevention measures should be adopted for a long deep buried tunnel construction. The results can provide evaluation of engineering safety of a long deep buried tunnel construction with scientific basis.

Abstract: Fractal grids can be used to design turbulent flows with low power losses and high turbulence intensities for intense yet economic mixing over a region of designed length and location. The introducing circle grid perforated plate is the main aim of this present paper. In this numerical work, we want to ascertain a new approach in turbulence generators on the structure of premixes flames using perforated plate fractal-grids pattern. In this paper, we compared circle grid perforated plate by varies using its diameters, spacing and number of holes on the plate. The result showed good perceptivity of the fractal generated turbulence and the fractal flow physics. The turbulent intensity can be increased by a grid with higher blockage ratio.

Abstract: Classic N-S equation has first order accuracy in both of time and space. It has only the terms of first order, without the terms of second or higher order. These terms are relative in time and space steps. The time and space steps, as basic elements of fluid research, should be only some finite quantities and not be infinitely near to zero as defined in mathematics. If the terms of second or higher order can be ignored depends on the value of the corresponding derivative multiplied. Compared with terms of first order, the terms of second or higher order can be ignored under the condition of laminar flow. However, under the condition of turbulent flow, these can’t be ignored yet. When turbulent flow develops fully, the terms of first order, compared with terms of second order, can be ignored. So, it is why classic N-S equations aren’t closed when they are used to analyze turbulent flow. On the basic, many different special forms of the second order accuracy N-S equations of incompressible fluid are derived.

Abstract: Unsteady, pressure driven in the gap between two parallel plates flow of two non-Newtonian incompressible second grade fluids is considered. The governing equations are established for the particular two-layer flow and analytical solutions of the equations that satisfy the imposed boundary conditions are obtained. The velocity of each fluid is expressed as function of the material constants, time dependent pressure gradient and other characteristics of the fluids. As part of the solution, an expression for the interface velocity is derived. We analyze the shift of the velocity maximum from one to another fluid as a function of variety of values of fluids’ parameters.