This is the image of Falcon Heavy lifting off from the Kennedy space centre. Lets zoom in a bit.
This is the result of firing 27 Merlin engines to produce about 5.5 million pounds of thrust. Thats a lot of heat and sound produced. Around 180dB to 220 dB of sound is produced during the launch of a rocket. Around 85dB of sound can cause permanent hearing loss to a human ear. The shock waves produced by the rocket can not only damage the rocket itself but also the surrounding buildings.
In order to suppress the sound, a large water tower which can dump upto 1 million pounds of water into the launchpad in just 40 seconds is placed nearby. Something like this:
The sound waves then travel along and are absorbed by the water molecules.
As the energy gets absorbed, they get heated up. Thus energy gets transformed from sound energy to heat energy.
By using this technique, the sound can be damped to about 145dB from 195dB.
Not only to suppress sound, it also extinguishes the fire caused due to the exhaust of the rocket.
