| dc.description.abstract | Computational Fluid Dynamics tools have been around for a couple of decades now. With the growing computing power, the speed and accuracy of these tools have improved tremendously. The ability to visualize flow is now a common feat on the powerful and speedy computers. Students of aerodynamics studies would benefit greatly not only with the abilities to simulate flows, but also to visualize them. Unfortunately, to use such tools, one has to be quite well-versed in the language of complex computational programming. The challenge for most aerospace or aeronautical undergraduate student is to understand the complicated world of aerodynamics through series of mathematical equations. Without the ability to see how flows behave in motion, the student can only imagine how the stall occurs over an airfoil or how the turbulent air looks like after separation happens. In this case, a (flow separation) picture will definitely speak more than a thousand words (or equations). Computational Fluid Dynamics offers the above capabilities, but with a catch - the user must know aerodynamics well enough so as not to blindly believe all the computer data being spewed out is correct. The phrase "garbage in, garbage out" will describe the situation most adequately if the user has little knowledge about setting the boundary conditions or fluid properties. Also, the more complex the simulation is, the longer it requires to compute the solution. Nowadays, as in all processes, flow simulation is expected to work fast, if not instantaneous. However, in the world of Computational Fluid Dynamics, typically the accuracy of the simulation is sacrificed for the speed in obtaining the solution or vice versa. To simplify the complex mathematics involved in Computational Fluid Dynamics, the Low Speed Virtual Wind Tunnel simulation is created. This program cuts down on the require information from the user in order to perform a simulation. The program is capable of taking an airfoil coordinates that is generated according to the user's specifications and provide a "quick and dirty" estimation of aerodynamic characteristics like lift, drag and pitching moment. In addition to that, a pressure flow field across the airfoil is created to show the pressure distribution of the airfoil. With further modification to the input coordinates data, an animation of the flow is produced. Thus this "picture speaks more than a thousand words" (or equations). By utilizing the speed of the computation, there are restrictions to the results obtained. The visualizations of the flows are extremely telling but the aerodynamics characteristics are skewed when flow separation occurs. Unsteady flow in flow separation requires longer computing time and information to give a more complete analysis. Therefore, results from high angles of attack in stall condition should be taken with some skepticism. Thus, the Low Speed Virtual Wind Tunnel simulation program remains an acceptable tool for students who are beginners to the field of aerodynamics and Computational Fluid Dynamics. The ability to visualize the flow field enhances the understanding of the mathematical flow equations is undeniable. This also gives the students an early taste of the power of Computational Fluid Dynamics in the years to come that would play a crucial role in the ever developing aerospace industry. | |
