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
VK Ltd a multi product company, furnishes you the following data relating to the year 2000. First half sales Second half sales Sales Rs.45000 Rs.50000 Total cost Rs.40000 Rs

Principles of fire risk assessment: The following principles of FRAs apply in the UK as they do in the USA: justifying assumptions, stating data sources,

how can you access the general purpose registers of Microprocessor in windows XP/2000/98...



How much heat in kJ is released when 4.1 grams of ethanol burns? C2H5OH(l) + 3 O2(g) ? 2 CO2(g) + 3 H2O(l), ?H = -1366.8 kJ/mol rxn

Let C(K) denote a European vanilla Call option with strike price K. Assume that all options are identical except for strike price, and strike prices satisfy (K1) What are the no-

Logic Gates: The term logic in electronics refers to the representation and logical manipulation of numbers usually in a code employing two symbols. i.e., bits. An electron

what is q meter

The following exchange rates are available to you. (You can buy or sell at the stated rates.) Mt. Fuji Bank ¥85.00/$ Mt. Rushmore Bank SF1.356/$ Mt. Blanc Bank ¥64.74/SF Assume t