I need the sketch!!!

Q$1.($a$)$ The continuous development of turbofan technology reveals that at the same

rated thrust a turbofan engine with low$-$bypass$-$ratio radiates substantially less

noise than by a turbojet. Sketch the magnitudes and patterns of noise radiation

of various sources in a low$-$bypass$-$ratio turbofan engine schematically shown in

Figure Q$1($a$).$

$(5$ marks$)$

Figure Q$1($a$)$

$($b$)$ Figure Q$1($b$)$ shows the configuration of a stator$-$rotor stage of the low$-$pressure

turbine of a turbofan engine. Explain, with sketches, the noise generation

mechanisms of broadband and tonal components of turbine noise.

$(11$ marks$)$

Q$4$ Figure Q$4$ shows typical spectra of fan$/$compressor noise and jet mixing noise of an

aircraft engine. Explain the characteristic features of the spectra and the physical

mechanisms responsible for the features identified. For each type of noise, sketch its

directivity and propose one noise control measure for each type of noise.

$(12$ marks$)$ Q$5.($a$)$ Figures Q$5$a and Q$5$b respectively show typical spectra of noise radiated by a diesel locomotive at full power and of noise due to wheel$-$track interaction under passenger coach. Explain, with sketches, the characteristic features of the spectra and the physical mechanisms responsible for the features identified. For each type of noise, propose one noise control measure.

$(8$ marks$)$

Figure Q$5$a$.$ Typical noise spectrum of locomotive at full power.

Figure Q$5$b$.$ Typical noise spectrum of wheel$/$track interaction.