Continuity equation - ducts and nozzles, Other Engineering

Continuity equation

If we consider the machine to be an open-ended duct, we find that the mass flow per second will depend on the density of the fluid and the volume flowing per sec:

644_ducts nozzals.png

Now volume flow = Area of duct x distance travelled (L)/ Time (sec)
But the distance travelled per second = Velocity.
Therefore, Mass flow = density x area x velocity.
This is known as the ‘continuity equation' and it is true for any steady flow system regardless of changes in the cross-sectional area of the duct.

INCOMPRESSIBLE FLUID FLOW.

Now consider an incompressible fluid as it flows through the duct system shown in the fig. 1.7. We know that the mass flow is of a constant value and, naturally, as the fluid enters the larger cross sectional area it will take up the new shape and the initial volume will now occupy less length in the duct. Therefore, in a given time, less distance is travelled and the velocity is reduced.
Thus we conclude that if the mass flow is to remain constant, as it must, an increase in duct area must be accompanied by a reduction in flow velocity, and a decrease in duct area must bring about an increase in velocity; we can express this action as - velocity varies inversely with changes

369_ducts.png

Posted Date: 9/11/2012 7:04:46 AM | Location : United States







Related Discussions:- Continuity equation - ducts and nozzles, Assignment Help, Ask Question on Continuity equation - ducts and nozzles, Get Answer, Expert's Help, Continuity equation - ducts and nozzles Discussions

Write discussion on Continuity equation - ducts and nozzles
Your posts are moderated
Related Questions
Vibrating beam accelerometer The electrodes are driven by a high frequency voltage (1 MHz). The displacement is measured using a phase detector from the change of capacitance b


Hey ,How are you? I need help in another class , its 1 credit class ( Engineering seminar ), how to choose s.d in this class , , ,so we want describing our project which is ( radi

.which type of financing is appropriate to each firm?

Series of Cash Flows Most engineering economic analysis involve more than a single return occurring after the investment is made. In such cases, the present worth or the futur


Vibration Analysis Gas turbine engines have extremely low levels of vibration compared to piston engines. Changes in vibration levels could occur therefore without being notic

EXPLAIN THE WORKING OF BASIC N-CHANNEL MOSFET SWITCH

Providing alternative escape routes: The first thing to check is if everyone can turn away from the fire and move safely away from it. For this to be the case there will

Gas metal arc welding (GMAW) is performed by using direct current reverse polarity as it gives both good cleaning action and fast filler metal deposition rates. A rather high weldi