|
|
| Line 1: |
Line 1: |
| {{About|fluid flow calculations|''Euler'''<u>'s</u>''' number''|e (mathematical constant)}}
| | Jayson Berryhill is how I'm known as and my wife doesn't like it at all. To climb is something I truly enjoy performing. For years she's been living in Kentucky but her spouse wants them to move. Office supervising is what she does for a living.<br><br>Here is my website ... online psychic reading ([http://m-card.co.kr/xe/mcard_2013_promote01/29877 learn the facts here now]) |
| | |
| The '''Euler number''' ('''Eu''') is a [[dimensionless number]] used in [[fluid flow]] calculations. It expresses the relationship between a local [[pressure]] drop e.g. over a restriction and the [[kinetic energy]] per volume, and is used to characterize losses in the flow, where a perfect frictionless flow corresponds to an Euler number of 1. The inverse of the Euler number is referred to as the '''Ruark Number''' with the symbol '''Ru'''.
| |
| | |
| It is defined as
| |
| | |
| :<math>
| |
| \mathrm{Eu}=\frac{p_\mathrm{upstream} - p_\mathrm{downstream}}{\rho V^2}
| |
| </math>
| |
| | |
| where
| |
| *<math>\rho</math> is the density of the fluid.
| |
| *<math>p_{\mathrm{upstream}}</math> is the upstream pressure.
| |
| *<math>p_{\mathrm{downstream}}</math> is the downstream pressure.
| |
| *<math>V</math> is a characteristic velocity of the flow.
| |
| | |
| The cavitation number has a similar structure, but a different meaning and use:
| |
| | |
| The '''Cavitation number''' ('''Ca''') is a [[dimensionless number]] used in flow calculations. It expresses the relationship between the difference of a local absolute pressure from the vapor [[pressure]] and the [[kinetic energy]] per volume, and is used to characterize the potential of the flow to [[cavitation|cavitate]].
| |
| | |
| It is defined as
| |
| | |
| :<math> | |
| \mathrm{Ca}=\frac{p - p_\mathrm{v}}{\frac{1}{2}\rho V^2}
| |
| </math>
| |
| | |
| where
| |
| *<math>\rho</math> is the density of the fluid.
| |
| *<math>p</math> is the local pressure.
| |
| *<math>p_\mathrm{v}</math> is the [[vapor pressure]] of the fluid.
| |
| *<math>V</math> is a characteristic velocity of the flow.
| |
| | |
| ==See also==
| |
| * [[Reynolds number]] for use in flow analysis and similarity of flows
| |
| | |
| ==References==
| |
| *{{cite book |authorlink=George Keith Batchelor |last=Batchelor |first=G. K. |year=1967 |title=An Introduction to Fluid Dynamics |location= |publisher=Cambridge University Press |isbn=0-521-09817-3 }}
| |
| | |
| {{NonDimFluMech}}
| |
| | |
| {{DEFAULTSORT:Euler Number (Physics)}}
| |
| [[Category:Dimensionless numbers of fluid mechanics]]
| |
| [[Category:Fluid dynamics]]
| |
Jayson Berryhill is how I'm known as and my wife doesn't like it at all. To climb is something I truly enjoy performing. For years she's been living in Kentucky but her spouse wants them to move. Office supervising is what she does for a living.
Here is my website ... online psychic reading (learn the facts here now)