What is Turbulence?
Turbulence is a form of movement which is characterized by an irregular or agitated motion. Both liquids and gases can exhibit turbulence, and a number of factors can contribute to the formation of turbulence. When a liquid or gas is moving smoothly and regularly, it is said to be exhibiting laminar flow, which is the opposite of turbulent flow. Many people interact with some variety of turbulence on a daily basis. This phenomenon is caused when an interruption or impediment is introduced to the flow. For example, a river may flow smoothly until it hits a boulder, at which point the water around the obstacle will become turbulent as it moves around or over it. In the air, turbulence can be caused by things such as the collision of two weather fronts, or by the formation of a storm. Air turbulence can also be caused by obstacles on the ground, ranging from mountains to buildings. While people understand what causes turbulence, it can sometimes be difficult to understand, because it is n
Let us first define what a flow is: a flow is the continuous movement of a fluid, i.e. either a liquid or a gas, from one place to another. Basically there exist two types of flows, namely laminar flows and turbulent flows. Roughly speaking we can say that a laminar flow is a ‘simple’ flow while a turbulent flow is a ‘complicated’ flow. We will illustrate what we mean by ‘simple’ and ‘complicated’ using the following, simple experiment. Go to your kitchen sink and open the faucet. The stream of water that emerges from your faucet is very smooth and very regular. The flow of water is smooth because all the water molecules move, at more or less the same speed, in the same direction. This is called a laminar flow. Furthermore, if you did not open the faucet too much, the water will also flow down the drain in a laminar flow. Now place a cup under the stream of water emerging from the faucet. Although the stream is still laminar, the flow pattern of the water in the sink has become very co
Turbulence is air movement that normally cannot be seen and often occurs unexpectedly. It can be created by many different conditions, including atmospheric pressure, jet streams, air around mountains, cold or warm weather fronts or thunderstorms. Turbulence can even occur when the sky appears to be clear. While turbulence is normal and happens often, it can be dangerous. Its bumpy ride can cause passengers who are not wearing their seat belts to be thrown from their seats without warning. But, by following the guidelines suggested on this site, you can help keep yourself and your loved ones safe when traveling by air. To keep you and your family as safe as possible during flight, FAA regulations require passengers to be seated with their seat belts fastened: • When the airplane leaves the gate and as it climbs after take-off. • During landing and taxi. • Whenever the seat belt sign is illuminated during flight. Why is it important to follow these safety regulations? Consider this: • I
Fluid turbulence was identified in 1949 by Von Neumann, one of the founders of modern computers, as one of the remaining grand challenges in physics. Today, almost 50 years later, it still is. It is a problem in applied physics, because almost certainly the equations for the physical mechanisms can be written down by anyone who has ever taken an undergraduate fluid mechanics course. The Navier-Stokes (NS) equations apparently contain all of turbulence, and so in a limited sense, there is no problem to be solved. Knowing the existence of a set of equations is of course not all the same thing as being able to solve them, or to know when solutions exist either mathematically, or in the physical world. The presence of nonlinear terms in the NS equations renders their direct solution impossible for all but the most carefully-chosen of problems.
