Fluid flow can be categorized as laminar, turbulent, or transitional. Laminar flow is smooth and predictable, while turbulent flow is chaotic and favored by rough surfaces and low viscosity fluids. Transitional flow combines both types. Turbulence is important in aviation, with wake turbulence and airfoil turbulence affecting aircraft performance. Methods to reduce turbulence are being researched.
Flow is the constant or continuous movement of a fluid, whether through a pipe, through an airfoil, or in the open air, such as in open air or the sea. This type of motion falls into one of three general categories: laminar flow, turbulent flow, or transitional flow. Supercomputers and special software are required to consider complex mathematical models of such flow behavior.
Laminar flow through a pipe can be visualized as a series of very thin layers – nested cylinders of fluid – from the inner surface of a pipe to its center. The characteristics that promote laminar flow are a smooth tube wall and high fluid viscosity. The outermost layer of fluid adheres to the tube. The other layers slide into each other at slightly increasing speeds as you get closer to the center. Laminar flow is moderately predictable and orderly.
Turbulent flow is a tumultuous flow, a flow complete with eddies and eddies. The word “turbulence” implies a mixing action, increasing or maintaining a uniform fluid composition throughout the contents of the tube. Turbulent flow is favored by a rough tube interior and low viscosity fluids. It is also favored by the increase in fluid density. An example of turbulent flow is that of blood through arteries.
Transitional flow is between the first two types. It combines laminar flow along the inside edge of a pipe with turbulent flow in between. Specialty mixer engineers design impellers that introduce transitional flow in highly viscous fluids that would normally exhibit laminar flow. This saves time and money on mixing.
Turbulent flow is of utmost importance to aviation in two ways. Turbulence in the surrounding air, produced by weather systems, is beyond the designer’s control. The other is the turbulence generated by the aircraft itself, especially its wings. This type of controllable turbulence comes from the wings and can be divided into wake turbulence and airfoil turbulence.
Wake turbulence is the flow generated by the wingtips of aircraft and often takes the form of a circular pattern of air perpendicular to the direction of flight. Airfoil turbulence is generated on the wing surface and causes the aircraft to drag and lose lift. Methods to reduce wake and airfoil turbulence are the subject of many theories and projects.
Protect your devices with Threat Protection by NordVPN