In
fluid dynamics
In physics, physical chemistry and engineering, fluid dynamics is a subdiscipline of fluid mechanics that describes the flow of fluids – liquids and gases. It has several subdisciplines, including (the study of air and other gases in motion ...
, a synthetic jet flow—is a type of
jet flow, which is made up of the surrounding
fluid
In physics, a fluid is a liquid, gas, or other material that may continuously motion, move and Deformation (physics), deform (''flow'') under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are M ...
. Synthetic jets are produced by periodic ejection and suction of fluid from an opening. This oscillatory motion may be driven by a piston or diaphragm inside a cavity among other ways.
[ (http://www.crcpress.com/product/isbn/9781439868102 )]
A ''synthetic jet flow'' was so named by Ari Glezer since the flow is "synthesized" from the surrounding or ambient fluid. Producing a convectional jet requires an external source of fluid, such as piped-in compressed air or plumbing for water.
Synjet devices
Synthetic jet flow can be developed in a number of ways, such as with an electromagnetic driver, a piezoelectric driver, or even a mechanical driver such as a piston. Each moves a membrane or diaphragm up and down hundreds of times per second, sucking the surrounding fluid into a chamber and then expelling it. Although the mechanism is fairly simple, extremely fast cycling requires high-level engineering to produce a device that will last in industrial applications.
For hot spot thermal management, the Synjet, commercially offered by Austin, Texas–based company Nuventix,
was patented in 2000 by engineers at Georgia Tech. The tiny synjet module creates jets that can be directed to precise locations for industrial spot cooling. Traditionally, metallic
heat sinks
A heat sink (also commonly spelled heatsink) is a passive heat exchanger that transfers the heat generated by an electronic or a mechanical device to a fluid medium, often air or a liquid coolant, where it is thermal management (electronics), ...
conduct heat away from electronic components and into the air, and then a small fan blows the hot air out. Synjet modules replace or augment cooling fans for such devices as microprocessors, memory chips, graphics chips, batteries, and radio frequency components. Additionally, SynJet technology has been used for the
thermal management of high power LEDs
Synthetic jet modules have also been widely researched for controlling airflow in aircraft to enhance lift, increase maneuverability, control stalls, and reduce noise. Problems in applying the technology include weight, size, response time, force, and complexity of controlling the flows.
A Caltech researcher has even tested synthetic jet modules to provide thrust for small underwater vehicles, modeled on the natural jets that squid and jellyfish produce. Recently, research team at the School of Engineering,
Taylor's University
Taylor's University (commonly referred to as Taylor's) is a private university in Subang Jaya, Selangor, Malaysia. It is Malaysia's top private university based on the QS World University Rankings.
It was founded in 1969 as a college, was awar ...
(Malaysia), successfully used synthetic jets as mixing devices.
[{{cite journal , last=Al-Atabi , first=Mushtak , title=Experimental Investigation of the Use of Synthetic Jets for Mixing in Vessels , journal=Journal of Fluids Engineering , publisher=ASME International , volume=133 , issue=9 , date=2011-09-01 , issn=0098-2202 , doi=10.1115/1.4004941 , page= , url=http://fluidsengineering.asmedigitalcollection.asme.org/article.aspx?articleid=1439115 , access-date=2014-02-07 , archive-date=2014-02-23 , archive-url=https://web.archive.org/web/20140223004547/http://fluidsengineering.asmedigitalcollection.asme.org/article.aspx?articleid=1439115 , url-status=live , url-access=subscription ] Synthetic jets prove to be effective mixing devices especially for shear sensitive materials.
References
Fluid dynamics