New vacuum-assisted tech makes airplane loo quieter

Airplane toilets are loud. For kids, they could be downright terrifying. Now, a team of US researchers has invented a vacuum-assisted toilet that is about half as loud as the regular airplane commode.

"People have told us they don't want their kids to be scared to use the bathroom on a flight," said lead researcher Kent Gee, Professor at the Brigham Young University. "We've used good physics to solve the problem."

It's been a really hard problem to solve because getting airplane toilets to flush with very little water requires a partial vacuum, which at 38,000 feet, pulls air at nearly half the speed of sound.

 

According to the research, conducted in a lab, an air-water mix in vacuum-assisted toilets travels more than 300 miles per hour.

When things move at that speed, any disturbance at all to the flow -- like the bend of a pipe or a valve -- generates significant noise.

Now that airplanes come with much quieter interiors, toilet flushes reverberate more throughout the cabin.

However, tests of the new contraption show aeroacoustically-generated noise declined 16 decibels during the flush valve opening and about 5-10 decibels when the valve is fully opened, the researchers reported in the Proceedings of Meetings on Acoustics journal.

To solve the problem, the team focused on three valve conditions during the flush cycle: the initial noise level peak associated with the flush valve opening, an intermediate noise level plateau associated with the valve being fully opened and the final noise level peak associated with the flush valve closing.

They added additional pipe to increase the distance between the toilet bowl and the flush valve and made the pipe attachment at the bowl more of a gradual bend as opposed to a sharp 90-degree angle.

The new vacuum-assisted technology can also be used for toilets on cruise ships, trains and even in new green building projects where people are looking at ways to reduce water usage.

--IANS

rt/mag/pcj