Can Bernaulli's theorem be applied on gases?

As Bernaulli's theorem is applied on fluids, so can we apply it on gases also?

Showing Answers 1 - 14 of 14 Answers

sks.shah Profile Answers by sks.shah

• Mar 31st, 2011

Yes it can be applied. That's why one can measure flow rate of gases across an orifice meter. Do correct me if I am wrong.

Balaji

• Oct 10th, 2011

yes it can be used, but limited for moderate mach numbers.

abubakar sohail

• Apr 9th, 2012

Of-course its applicable to fluids . and we count gases in fluids but with care as both liquids & gases show different behavior w.r.t viscosity & some other factors.

jitendra sharma

• Jul 29th, 2014

Because BER. EQ. is used only for in-compressible fluid and gas is com.

neeru srangal Profile Answers by neeru srangal

• Aug 17th, 2014

Yes, bernaullis theorem can be applied to incompressible fluids (liquids) and compressible fluids (gases) in the range of low mach number (less than 0.3).

Vipin Agrawal

• Nov 21st, 2014

Since gases are always compressible and the main assumption is the Bernoulli equation is that flow should be in-compressible, So Bernoulli cant be applied on gases but naiver stokes is always applicable for any type of fluids.

Vipin Agrawal

• Nov 21st, 2014

I think the answer is No.

Since gases are always compressible and the main assumption is the bernauli equation is that flow should be in-compressible, So Bernauli cant be applied on gases but navier stokes is always applicable for any type of fluids.

ashwin

• Dec 7th, 2015

Yes, gases having mach number above 0.3 bernouli theorem can be applied

Sarthak

• Dec 11th, 2015

Yes it can be used in case of gases, only if the gas could be considered incompressible, which would happen for low mach numbers. Also, venturimeter and orificemerers are based on Bernoulli theorem and are used to measure flow rates of gases

arunima gupta

• Feb 8th, 2016

Bernoulli's equation applicable on air till its velocity is .3 of sounds velocity or we can say if Mach no is near to 3..at this time air behave as incompressible fluid because its velocity is too high to be compressible...and according to Bernoulli's equation demand its fullified incompressibility term.

Vasu Roy

• May 31st, 2016

Bernoullis equation is sometimes valid for the flow of gases: provided that there is no transfer of kinetic or potential energy from the gas flow to the compression or expansion of the gas. If both the gas pressure and volume change simultaneously, then work will be done on or by the gas. In this case, Bernoullis equation – in its incompressible flow form – cannot be assumed to be valid. However, if the gas process is entirely isobaric, or isochoric, then no work is done on or by the gas, (so the simple energy balance is not upset). According to the gas law, an isobaric or isochoric process is ordinarily the only way to ensure constant density in a gas. Also the gas density will be proportional to the ratio of pressure and absolute temperature, however this ratio will vary upon compression or expansion, no matter what non-zero quantity of heat is added or removed. The only exception is if the net heat transfer is zero, as in a complete thermodynamic cycle, or in an individual isentropic (frictionless adiabatic) process, and even then this reversible process must be reversed, to restore the gas to the original pressure and specific volume, and thus density. Only then is the original, unmodified Bernoulli equation applicable. In this case the equation can be used if the flow speed of the gas is sufficiently below the speed of sound, such that the variation in density of the gas (due to this effect) along each streamline can be ignored. Adiabatic flow at less than Mach 0.3 is generally considered to be slow enough

JDR

• Jun 20th, 2017

No, Because it is only applicable for incompressible fluids. And gases are compressible.

deewakar vats

• Aug 13th, 2017

sorry sir but there are certain assumption in bernaullis theorem that
1 flow is steady
2 flow is ideal
3 flow is incompressible or const density so a gas is a complessible and density can vary as per the equation
v2/g + P/w +y=const

Mohamed Asharaf

• Oct 7th, 2017

The assumptions in which Bernoullis equation derived are

1.Inviscid Flow
3.Density is Constant
4.Along the Stream-line

Since the gas flow obey these properties, we can conclude that Bernoullis equation can be applied to gas flow.

also it can be applied to compressible and in-compressible flows

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