Surface drag
نویسندگان
چکیده
I will deiscuss the drag of particles on granular surfaces by a fluid. I will present simulations using FLUENT of Aeolian saltation under Earth and Mars conditions obtaining among others the static and dynamic threshold shear and the height of the saltation layer as function of the wind strength. A universal quadratic increase of the saturated flux as function of the difference from the threshold is established.
منابع مشابه
EXPERIMENTAL INVESTIGATION OF DRAG REDUCTION ON AHMED MODEL USING A COMBINATION OF ACTIVE FLOW CONTROL METHODS
Aerodynamic drag is an important factor in vehicles fuel consumption. Pressure drag which is the main component of total drag is a result of boundary layer separation from vehicle surface. Flow control methods are applied to avoid or at least delay separation. Depending upon whether these methods consume energy to control the flow or not, they are called active or passive control methods. In th...
متن کاملشبیه سازی عددی خزه های دریایی چسبیده به بدنه شناورها و بکارگیری روشهای کاربردی و نوین به منظور کاهش نیروی درگ ناشی از آنها
In this research, the effects of foulings on the outer surface of a marine vessel have been studied using the Computational Fluid Dynamics (CFD) methods. To this end, a proper turbulence model was considered and validated for the simulations. The simulation results for different fouling grades indicated that existing of a thin layer of slime could make 4.58 % increase in drag force; however, fo...
متن کاملVerification of a CFD solver in near ground effect for aerodynamic behavior of airfoil NACA 0015
Numerical investigation was performed on NACA 0015 which is a symmetric airfoil. Pressure distribution and then lift and drag forces are verified. Changing of ground clearance was a considerable point. Also the angle of attack was changed from 0° to 10°. Pressure coefficient reaches its higher amounts on the wing lower surface when the ground clearance diminishes. Increment of the angle of atta...
متن کاملInvestigation of Drag Coefficient at Subcritical and Critical Reynolds Number Region for Circular Cylinder with Helical Grooves
Drag reduction of an object is the major concern in many engineering applications. Experimental studies have been carried out on circular cylinder with helical grooves in a subsonic wind tunnel. Different cases of helical grooves with different pitches, helical groove angles and number of starts of helical groove on circular cylinder are tested. Experimental results show the drag coefficient is...
متن کاملAnalysis of air injection system for drag reduction in high speed vessels using numerical simulation software ANSYS-Fluid Flow
Many existing phenomena in nature are considered new design ideas in various fields of industry. Bionics is the application of biological methods and systems found in nature to the study and design of engineering systems and modern technology. By performing bionic review, the researchers found the penguins by delivering air locked under their wings and creating air bubbles, the drag significant...
متن کاملAnalysis of Drag Reduction Methods and Mechanisms of Turbulent
Turbulent flow is a difficult issue in fluid dynamics, the rules of which have not been totally revealed up to now. Fluid in turbulent state will result in a greater frictional force, which must consume great energy. Therefore, it is not only an important influence in saving energy and improving energy utilization rate but also an extensive application prospect in many fields, such as ship doma...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008