To investigate the velocity distribution of a circular air jet at a number of stations along the length, to reveal how a uniform jet mixes with its surroundings by using a pitot-static tube to measure the velocity of the fluid in the jet.
The pitot static tube measures two pressures, P0 and P, the Total and Static pressures respectively.
However, in this experiment the error can be considered as negligible
A fan supplies air to a nozzle, which can provide a circular uniform jet of air. The nozzle is 30 mm in diameter. The velocity distribution in the jet is measured using a pitot static tube. The Pitot-static tube can be traversed across the jet diameter and also across its length by sliding the support against a millimeter scale to record its position. The pitot static tube is connected to an inclined manometer.
7.2 Measure the air velocity at points along the horizontal diameter at x=2D. Plot the variation of v with y as you take your readings. Use your judgment over how many points you need, ensuring that you locate the endpoints at the edge of the jet
7.4 The graphs should be symmetrical about the centerline. Decide for which graph, which value for y is at the center so that by subtraction, it is possible to plot V against radius r, measured from the centerline of the jet.
The pressure in the center of the jet is higher at the point of origin. The pressure stabilizes further away to the point of origin to match the surrounding pressure and hence the jet spreads out as it flows in order to reduce its density.