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 lin August 30, 2005 15:19

help! air viscosity versus pressure

Does anybody know the relationship between the air's viscosity and the pressure?(0.1 to 10000 times of the atmosphere pressure).Thanks a lot!!

 Isra bani hani July 26, 2006 05:00

Re: help! air viscosity versus pressure

Does anybody know the relationship between the air's viscosity and the pressure?(0.1 to 10000 times of the atmosphere pressure).Thanks a lot!!

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Post Response

 ginger December 7, 2006 20:20

Re: help! air viscosity versus pressure

It's basically a measure of temperature. ten thousand atmospheres, gas will not be acting ideal at those temperatures, actually forget this, when you figure it out would you email me till then ther's an interesting viscosity calculator on the internet.

 alirez July 17, 2007 02:13

Re: help! air viscosity versus pressure

please send to me the air viscosity vs temprature table

 Tom Liston, P.E., Mechanical Engineer August 30, 2007 20:02

Re: help! air viscosity versus pressure

What is the viscosity of air at 0.56 atmospheres, 70F?

I'm computing the difference of arrow launch angle at 15,000 ft above sea level versus launch angle at sea level.

 GOPALAKRISHNAN September 11, 2007 01:06

Re: help! how to calculate air viscosity

i urgently in need ,how to calculate the viscosity and renolds number.suppose my diameter=.33 ft, velocity =65ft/sec and density=0.075lbs/ft3 how can i calculate renolds number.please help me sir.

 S CHATTERJEE March 11, 2008 08:23

Re: help! air viscosity versus pressure

please send to me the air viscosity vs pressure table and also how to calculate air friction coefficient while a rotor is rotating inside stagnant air

 Ramesh babu September 2, 2008 11:45

Re: help! air viscosity versus pressure

we have micro porosity issue with aluminium casting, where the application of the products uses ink as media, which is more viscosity than air which is used for qualifications & testing. Please mail me the relationship, if u receive from anyone. I am looking fo the same.

 ramkumar January 27, 2009 13:48

Re: help! air viscosity versus pressure

 umar February 13, 2009 01:47

Re: help! air viscosity versus pressure

You're unlikely to find anything that calculates viscosity as a function of pressure because it varies little (Crane says no more than 10% up to a pressure of 500 bar.pressure variatiom has hardly any effect on viscosity.

 Robert July 21, 2009 17:04

I have the same question regarding the releationship of air viscosity versus pressure. I my case, I am dealing with vacuum. I have noticed that the actual vacuum experienced in our systems is about 20-30% lower that what we calaculate using Reynolds number and friction facrtor calculated with standard air viscosity values.
I am wondering if vacuum "lack of air" reduces the viscosity.
I have not had much luck finding a formula to relate pressure and viscousity of air.

 mwaqas March 18, 2015 14:45

Hello everyone

Have you found the relationship b/w viscosity and pressure. Please let me know also. thank you

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