|
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
On NASA TV's STS-130 Flight Day Highlights segment aired Wednesday
afternoon, there was a short clip showing shuttle astronaut Kathryn Hire preparing an ISS ATU (Audio Terminal Unit) for installation in the new Cupola module. Two hoses were seen coming out of the bottom, and a commentator said these were for a water cooling loop. So, are all ATUs on the station similarly connected to water cooling? Or is this one set up differently because of possible sun heating when the Cupola windows are open? In the former case, what is there inside that's dissipating enough power to make this necessary? I understand that relying on forced-air or convective cooling of electronics on ISS is undesirable, but why would the ATU be emitting any significant heat to begin with? Isn't it basically just an intercom/phone panel? curious, -- Jordan. |
#3
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
On Thu, 18 Feb 2010 10:02:40 GMT, "Brian Gaff"
wrote: I was wondering about the heat aspect of the large windows though. One supposes they will only open for short periods or the cooling for that part of the station could well be very big. It's probably not a serious problem, as the Cupola is on the Earth-facing side of the Station, so it won't be in direct sunlight very often. Brian |
#4
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
In article ,
Brian Gaff wrote: I'd have no idea. Seems odd that some[thing] like that would get very warm in any case. Are we sure that was all it was? It was definitely an ATU. Similar units exist all over the station, but others I've seen were all built into bulkheads, with any umbilical attachments hidden away. I found an STS-130 photo on NASA' site that shows three of these mounted side-by-side in the airlock. All appear to be identical, and the resolution's good enough to make out most of the controls. Since you can't see that photo, I'll describe it. There's a large speaker grill in the upper-left, with a microphone jack next to it, and some unknown connector (or button?) just below that, a 2x16 character alphanumeric display (looks like LED or EL) in the center, above a phone-style keypad, with Transmit and Receive LED's near the bottom. Control buttons along the right-hand side are Push-to-talk/ON, Page, Xmit Mode, up/down arrows, Talk/Listen, Mon, Vox, and Vol. Center column: Dial/Ans, Hang Up, Conf/Listen, 2nd ("Shift" for keypad?) The keypad has LOG where * would be on a phone (2nd function: "Brite"), and CLR (2nd: "BIT?" hard to make this out) in place of pound. Most number buttons have two extra function labels, one on the button itself identifying places to call within ISS: 1 HAB (I wonder where this one actually ended up?) 2 no label 3 NODE (do they hit 1, 2, or 3 afterwards?) 4 LAB 5 CF ("centrifuge facility" perhaps, for the cancelled CAM?) 6 CPLA (cupola) 7 JEM 8 ESA (probably Columbus) 9 RSA (Zvezda?) 0 PIN or FIN (no idea!) Each also has ar label above, some of which look to be outside communication channels: 1 GND 2 UHF 3 A/L (one of those 3 airlock panels?) 4 DAG 5 DAA 6 DIA 7 EMU (for speaking to EVA crews outside?) 8 EX ON 9 EX OFF Heh, maybe I'm the only one who considers this remotely interesting... I was wondering about the heat aspect of the large windows though. One supposes they will only open for short periods or the cooling for that part of the station could well be very big. I wonder if the inverse is also true, ie, when in the dark, does energy radiate out that way? I thought the multi pane design was supposed to protect people from the extremes. It was implied during installation commentary that there are water loops running through the window frames as well, so that probably helps. There could also be a coating on one set of panes to reflect all/most infrared back out (common enough with energy-efficient windows on the ground). -- Jordan. |
#5
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
In article ,
Brian Thorn wrote: On Thu, 18 Feb 2010 10:02:40 GMT, "Brian Gaff" wrote: I was wondering about the heat aspect of the large windows though. One supposes they will only open for short periods or the cooling for that part of the station could well be very big. It's probably not a serious problem, as the Cupola is on the Earth-facing side of the Station, so it won't be in direct sunlight very often. Early assembly sequences had it going on the port side of Node 1, though, and a later revision on Node 3 forward (with Node 3 on Unity nadir, as originally intended). So, Cupola's design must have been able to accomodate any increased sun exposure from either of those locations. Brian -- Jordan. |
#6
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
I don't see any provision for water cooling of the ATU from these
photos. Are you sure she was talking about the ATU? http://www.angelfire.com/ego/porterclark/airmock/ Dave |
#7
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
Another possibility, the cooling lines were for all the electronics
in the cupola not just the ATU? Cooling could then be provided either directly through metal-on-metal conduction or via fans blowing convection air across cooling fins directly coupled to the water lines. ? Dave |
#8
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
David Spain writes:
I don't see any provision for water cooling of the ATU from these photos. Are you sure she was talking about the ATU? http://www.angelfire.com/ego/porterclark/airmock/ The captions on these photos make clear that these ATUs are *not* configured for flight. So one thought is that perhaps the flight ready configuration has a metal 'jacket' surrounding it that contains the plumbing for water cooling? The rear-facing photo also show an unattributed connector at the top of the ATU box, I have no idea what this does or is for. The captions also state that the boxes work in the rack as they are with no special cooling apparatus present that I can see. They say the boxes are only 'warm' to the touch not hot, which isn't surprising. I'm not a NASA sub, so I can't get access to their technical database for ISS that might allow me to pull the schematics on the ATU and the Harris Corp. website isn't helpful here either (not surprising). Sounds like you'll need help from an insider.... Jorge? Charlie? Dave |
#9
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
First thought was that ATUs are considered essential equipment and would
have to work even in a depressurised environment (where air cooled can't work). But in a depressurised environment, sound carries rather poorly :-) One needs to consider that the CBM provides for air flow in one direction only (I believe that it draws air from compartment and ducts it to destiny). So with the CBM hatch closed, there would be no actual air ventilation. Air temperatuve in the Copulate would then rise significantly. This might explain the need to water cool the unit. (CBM provides for bidirectional water cooling flows). Whether all ATUs are water cooled or only those in environments that are harsh, I do not know. If there is an ATU in the airlock for instance, it would also likely be water cooled. Even though it might not be of use when the airlock is depressurised, it would still need to be kept at proper temperature as to not fry the electronics. ATUs in normal compartments such as nodes and labs might be air cooled since they would not be exposed to any harsh environments. |
#10
|
|||
|
|||
ISS ATU's (communication panels) need water cooling? Why?
David Spain wrote:
David Spain writes: I don't see any provision for water cooling of the ATU from these photos. Are you sure she was talking about the ATU? http://www.angelfire.com/ego/porterclark/airmock/ The captions on these photos make clear that these ATUs are *not* configured for flight. So one thought is that perhaps the flight ready configuration has a metal 'jacket' surrounding it that contains the plumbing for water cooling? The rear-facing photo also show an unattributed connector at the top of the ATU box, I have no idea what this does or is for. The captions also state that the boxes work in the rack as they are with no special cooling apparatus present that I can see. They say the boxes are only 'warm' to the touch not hot, which isn't surprising. I'm not a NASA sub, so I can't get access to their technical database for ISS that might allow me to pull the schematics on the ATU and the Harris Corp. website isn't helpful here either (not surprising). Sounds like you'll need help from an insider.... Jorge? Charlie? Porter Clark used to post here... maybe he will de-lurk. |
|
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Solar Panels | adam eddy | Space Shuttle | 5 | October 5th 08 08:31 PM |
WATER WATER WATER FOR AUSTRALIA... HOPELESSLY PRAYING MR HOWARD | [email protected] | Astronomy Misc | 3 | February 11th 07 10:57 AM |
Saturn S-IVB Panels | [email protected] | History | 17 | November 23rd 05 02:56 PM |
Dark Sky Panels | JOHN PAZMINO | Amateur Astronomy | 0 | August 12th 03 08:26 AM |
RCC panels | Hallerb | Space Shuttle | 10 | July 28th 03 11:41 PM |