Q2. (a)
The nozzle has a diameter of 2 cm. Air at 25°C is discharged from a nozzle at a
near-uniform velocity of 20 m/s. At x distance downstream from the nozzle, the
turbulent jet velocity distribution can be described with the following formula:
$u = 9.1 \exp(-0.00104r^2)$ m/s, with $r$ in mm
By utilizing $\rho = 1.184 kg/m^3$, answer the following:
(i) Evaluate the jet momentum $J$ at section x [unit in kg-m/s$^2$].
(4 marks)
(ii) Evaluate the momentum at the nozzle [unit in kg-m/s$^2$].
(3 marks)
(iii) Compare your findings obtained from (i) with the momentum at the
nozzle obtained from (ii).
Briefly explain your findings.
(2 marks)
(iv) Determine the volume flow of air entrained into the jet, if any, between
the nozzle and section x.
(7 marks)