Search results
Results from the WOW.Com Content Network
Modern construction of guitars is an example of using rarefaction in manufacturing. By forcing the reduction of density (loss of oils and other impurities) in the cellular structure of the soundboard, a rarefied guitar top produces a tonal decompression affecting the sound of the instrument, mimicking aged wood.
The technique of rarefaction was developed in 1968 by Howard Sanders in a biodiversity assay of marine benthic ecosystems, as he sought a model for diversity that would allow him to compare species richness data among sets with different sample sizes; he developed rarefaction curves as a method to compare the shape of a curve rather than absolute numbers of species.
Free molecular flow describes the fluid dynamics of gas where the mean free path of the molecules is larger than the size of the chamber or of the object under test. For tubes/objects of the size of several cm, this means pressures well below 10 −3 mbar.
[4] [5] In these rarefied flows, the Navier-Stokes equations can be inaccurate. The DSMC method has been extended to model continuum flows (Kn < 1) and the results can be compared with Navier Stokes solutions. The DSMC method models fluid flows using probabilistic simulation molecules to solve the Boltzmann equation. Molecules are moved through ...
Neon lighting consists of brightly glowing, electrified glass tubes or bulbs that contain rarefied neon or other gases. Neon lights are a type of cold cathode gas-discharge light. A neon tube is a sealed glass tube with a metal electrode at each end, filled with one of a number of gases at low pressure.
With increasing height, the atmosphere becomes more rarefied, which increases the mean time between collisions of molecules (also known as mean free time). The maximum frequency a sound wave can have and still be able to propagate in a gas is roughly the inverse of the mean free time [3] (molecular mean free path divided by average molecular ...
The MARHy Hypersonic low density Wind Tunnel, located at the ICARE [1] Laboratory in Orléans, France, is a research facility used extensively for fundamental and applied research of fluid dynamic phenomena in rarefied compressible flows. Its name is an acronym for Mach Adaptable Rarefied Hypersonic, and the wind tunnel is recorded under this ...
The Knudsen number is a dimensionless number defined as =, where = mean free path [L 1], = representative physical length scale [L 1].. The representative length scale considered, , may correspond to various physical traits of a system, but most commonly relates to a gap length over which thermal transport or mass transport occurs through a gas phase.