11
$\begingroup$

It is a well-known fact that it is quite noisy aboard the ISS. Fans and pumps working all the time, valves closing/opening etc. Crew members live through it with ear protection, but that doesn't mean we shouldn't try to make long-term stay in space more comfortable.

How much will it cost mass-, time-, and money-wise to reduce noise by any combination of means*?

We've long had an industry (building submarines) making considerable money on noise reduction, and loads of expertise. Can this expertise be applied to ECLSS (environment control and life support system) aboard manned spacecraft?

* Better bearings, noise cancellation, enhanced computer modelling of vibration & transient sounds, etc.

$\endgroup$
  • $\begingroup$ Some astronauts started sleeping inside the ATV (if there is one docked). Apparently, it is much less noisy in there ... $\endgroup$ – s-m-e Aug 22 '13 at 17:35
10
$\begingroup$

Yes, noise is a problem on the ISS - this graph shows noise levels in various parts of the station:

noise levels

A quick search for spacecraft noise reduction revealed this rather interesting NASA technical note:

It is important to control acoustic noise aboard the International Space Station (ISS) to provide a satisfactory environment for voice communications, crew productivity, and restful sleep, and to minimize the risk for temporary and permanent hearing loss.

...

The paper goes on to show what is being done on the station to combat the noise levels - such as 'acoustic lining' on air vents:

enter image description here

Also, an 'acoustic cover' was put over the air conditioning unit:

T

There are many more examples in the paper - it's a good read.

$\endgroup$
3
$\begingroup$

What is being done?

Drawing on an excellent find by @Undo, here are concrete technologies currently in use:

  • Replacing old fans by new ones (with CNC-machined blades that have been optimized through rigorous CFD modelling).
  • Putting mufflers, acoustic covers, vibration isolation, and acoustic lining into fans/air ducts, wrapping fluid lines in air conditioning loops.
  • Putting doors onto crew quarters in the Zvezda service module.
  • Fixing individual pieces of equipment across the station.

Unresolved issues remain:

  • Oxygen Generation System (in the US segment) and Vozdukh (in the Russian segment) are waaaay too noisy.
  • Water recovery pumps/separators.
  • Toilets.
  • Exercise devices (ARED, in particular).

It is also apparent that RSC Energiya, the main designer of the Russian segment, was prodded by the Americans to reduce acoustic signatures, and that its technologies are somewhat archaic.


The framework

Goodman, Grosveld. Acoustics in habitable space vehicles and enclosures (pdf). Rome, Italy, 2008.

What’s required to ensure acceptable acoustic levels in crew compartments:

  • Good set of acoustic requirements
  • Noise Control, compliance & verification
  • Management relationship

What I am sad to see:

  • Noise cancellation isn't exactly on the menu
  • Astronauts/cosmonauts do not often have the leverage to make noise control part of the design objective function
  • Equipment manufacturers aren't keen on preventing the problem from popping up
$\endgroup$
  • $\begingroup$ You'd think it would be a consideration due to fatigue factor. For short-term exposure (hours, perhaps days), noise could perhaps be tolerated, but you'd think that for long-term (months), it would affect crew performance. One would think that any crew performance issue in an environment as unforgiving as space would be a safety issue, and that would warrant consideration. $\endgroup$ – Anthony X Apr 22 '15 at 0:22

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.