Runge's theorem: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
Undid revision 506003880 by 24.240.40.31 (talk)
 
en>Policron
m Added an external link (EOM).
Line 1: Line 1:
The author is known as Wilber Pegues. For years she's been living in Kentucky but her husband desires them to move. To climb is some thing I really appreciate performing. Distributing production is exactly where my main income comes from and it's something I really appreciate.<br><br>My website ... online psychic chat ([http://www.prograd.uff.br/novo/facts-about-growing-greater-organic-garden www.prograd.uff.br])
{{No footnotes|date=August 2011}}
The '''Magnetic Reynolds number''' ('''R<sub>m</sub>''') is a [[dimensionless quantity|dimensionless group]] that
occurs in [[magnetohydrodynamics]]. It gives an estimate of the effects of magnetic [[advection]] to magnetic [[diffusion]], and is typically defined by:
: <math>\mathrm{R}_\mathrm{m} = \frac{U L}{\eta}</math>
where
* <math>U</math> is a typical velocity scale of the flow
* <math>L</math> is a typical length scale of the flow
* <math>\eta</math> is the [[magnetic diffusivity]]
 
== General Characteristics for Large and Small R<sub>m</sub> ==
 
For <math>\mathrm{R}_\mathrm{m} \ll 1</math>, advection is relatively unimportant, and so
the magnetic field will tend to relax towards a purely diffusive state, determined by the boundary conditions rather than the flow.
 
For <math>\mathrm{R}_\mathrm{m} \gg 1</math>, diffusion is relatively unimportant on the length scale ''L''. Flux lines of the magnetic field are then advected with the fluid flow, until such time as gradients are concentrated into regions of short enough length scale that diffusion can balance advection.
 
== Relationship to the Reynolds Number and Péclet Number ==
 
The Magnetic Reynolds number has a similar form to both the [[Péclet number]] and the [[Reynolds number]]. All three can be regarded as giving the ratio of advective to diffusive effects for a particular physical field, and have a similar form of a velocity times a length divided by a diffusivity.  The magnetic Reynolds number is related to the magnetic field in an MHD flow, while the Reynolds number is related to the fluid velocity itself, and the Péclet number a related to heat. The dimensionless groups arise in the non-dimensionalization of the respective governing equations, the  [[Faraday's law of induction#The Maxwell-Faraday_equation|induction equation]], the [[Navier–Stokes equations|momentum equation]], and the [[heat equation]].
 
==See also==
 
* [[Lundquist number]]
* [[Magnetohydrodynamics]]
* [[Reynolds number]]
* [[Péclet number]]
 
{{NonDimFluMech}}
 
== References ==
* {{ScienceWorld|title=Magnetic Reynolds Number|urlname=physics/MagneticReynoldsNumber}}
* Moffatt, H. Keith, 2000, [http://www.igf.fuw.edu.pl/KB/HKM/PDF/HKM_122_s.pdf Reflections on Magnetohydrodynamics]. In: ''Perspectives in Fluid Dynamics'' (ISBN 0-521-53169-1) (Ed. G.K. Batchelor, H.K. Moffatt & M.G. Worster) [[Cambridge University Press]], p347-391.
* P. A. Davidson, 2001, "''An Introduction to Magnetohydrodynamics''" (ISBN 0-521-79487-0), [[Cambridge University Press]].
 
[[Category:Dimensionless numbers of fluid mechanics]]
[[Category:Fluid dynamics]]
[[Category:Magnetohydrodynamics]]

Revision as of 22:37, 24 June 2013

Template:No footnotes The Magnetic Reynolds number (Rm) is a dimensionless group that occurs in magnetohydrodynamics. It gives an estimate of the effects of magnetic advection to magnetic diffusion, and is typically defined by:

Rm=ULη

where

General Characteristics for Large and Small Rm

For Rm1, advection is relatively unimportant, and so the magnetic field will tend to relax towards a purely diffusive state, determined by the boundary conditions rather than the flow.

For Rm1, diffusion is relatively unimportant on the length scale L. Flux lines of the magnetic field are then advected with the fluid flow, until such time as gradients are concentrated into regions of short enough length scale that diffusion can balance advection.

Relationship to the Reynolds Number and Péclet Number

The Magnetic Reynolds number has a similar form to both the Péclet number and the Reynolds number. All three can be regarded as giving the ratio of advective to diffusive effects for a particular physical field, and have a similar form of a velocity times a length divided by a diffusivity. The magnetic Reynolds number is related to the magnetic field in an MHD flow, while the Reynolds number is related to the fluid velocity itself, and the Péclet number a related to heat. The dimensionless groups arise in the non-dimensionalization of the respective governing equations, the induction equation, the momentum equation, and the heat equation.

See also

Template:NonDimFluMech

References

  • Is a upcoming condominium located within the neighbourhood of Hillview The Singapore government has put in place a brand new subsidised pancreas transplant programme (Thinkstock photo). Within the latest effort to spur investment in blighted areas of one of the metropolis's poorest neighborhoods, Chicago plans to promote a number of hundred properties for the value of a sweet bar.

    SpaceX can also be gearing up to launch from Vandenberg Air Pressure Base in California. This web site affords access to polar orbits, which many Air Force payloads and environmental monitoring satellites require. A satellite in polar orbit can expose its sensors to changing slices of the Earth rotating beneath it. On this means, the entire globe could be seen in a couple of days or much less. Better spaceflight economics — especially diminished launch costs — have lengthy been thought of important for strong improvement of the photo voltaic system's potentially liveable frontiers. Musk has repeatedly and publically said his desire, and his firm's aim, to explore and settle Mars District 19, Freehold strata cluster landed Shutter bus service to MRT station Freehold Mixed improvement

    Affiliation charges needs to be paid by each rental owner, weather you are dwelling in it or not, and even if you have rented the property. So, whether you employ the amenities and amenities at the condominium, you'd any how should pay for them. JOHOR BAHARU, Jan 22 (Bernama) — The property market in Johor Baharu and Iskandar Malaysia has been negatively affected by the cooling measures introduced by the authorities to handle rising property costs, says the Real Estate and Housing Developers' Association of Malaysia (Rehda). District 18, ninety nine years LH Executive Condo District 25, 99 years LH Executive Apartment District 19, 99 years LH Government Condominium pipelines. Property owners have no various but to pay up. There is not any different sensible Hottest Launch D'Leedon

    To not fear, we'll maintain you in our VIP Precedence record for future new properties in singapore launch VIP Preview. We'll contact you to identify your wants and recommend relevant tasks, both new launch or resale properties that probably match your standards. If you happen to're on the lookout for resale property, resembling these few years old, or just bought Temporary Occupation Allow (HIGH), chances are you'll click here here for fast search and submit your shortlisted listings to us, we'll check and name you for viewing.

    After acquiring a Sale License (topic to authorities conditions meant to protect folks shopping for property in Singapore), he may proceed to sell items in his growth. Property Launches Listings Map (Singapore & Iskandar Malaysia) - All Properties Listed In SGDevelopersale.com Consumers do NOT, and will NOT, should pay any agent any fee, when buying property in Singapore. PropertyLaunch.sg , is a site with the aims to supply quality, accurate and well introduced information to all our clients or anyone who're eager on new property launches in Singapore. Marina One Residences By Malaysia Khazanah & Singapore Temasek. SINGAPORE – Singaporeans are streets ahead of every other group of foreigners snapping up property developed by UEM Dawn at Iskandar Malaysia.

    Try our Featured Launches on this website, or just find the very the top left venture from the homepage of www.singaporepropertylisting.com ! That is the latest new launch mission, and normally VIP Preview might be held within 3 weeks from the time the undertaking surface on the highest left homepage. District 19, Freehold condominium District 15, Freehold Cluster landed home Earlier than one can fault the company giant for opening a restaurant in a historic landmark, it must first be famous that this mansion - known by locals as the Denton Home - was abandoned and on the breaking point earlier than McDonald's bought the property in the eighties Continuereading "Trilive at Kovan Preview Launch Quickly" Just TOP Urban Resort Condominium Are We There But? (at Propwise.sg)

    In an interview with HOUSE.com final November, Musk characterized the colonization of Mars as a partnership between commercial firms and governments. He put a roughly estimated value of $36 billion on the enterprise. A strong business spaceport — in Brownsville, Texas or any of the other websites now into account — would likely put SpaceX in a much better place to self-fund a minimum of a portion of that aim. Freehold Close to Mountbatten MRT Guillemard Highway Handle Quick Drive To CBD & City Close to New Sports Hub & Stadium Straightforward Entry To Major Expressways (PIE, KPE, and so forth) & Nicholl Freeway Excellent Investment @ Very Affordable Costs Mon Jervois is an exclusive new condominium consisting 5 blocks of 5 storey residential items at Jervois Highway.
  • Moffatt, H. Keith, 2000, Reflections on Magnetohydrodynamics. In: Perspectives in Fluid Dynamics (ISBN 0-521-53169-1) (Ed. G.K. Batchelor, H.K. Moffatt & M.G. Worster) Cambridge University Press, p347-391.
  • P. A. Davidson, 2001, "An Introduction to Magnetohydrodynamics" (ISBN 0-521-79487-0), Cambridge University Press.