Questions tagged [cooling]
The cooling tag has no usage guidance.
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How do ablatively cooled rocket engines compare to regeneratively cooled ones, in terms of mass?
Assuming equivalent thrust and single continuous burn duration, is there a figure that roughly tells the difference in mass between these two engines cooling methods? This question focuses on first ...
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Estimations for Gas-Side Wall Temperature Within Rocket Engines
I'm in the process of reading Modern Engineering for Design of Liquid Propellant Rocket Engines and am stuck on this one example given in chapter 4 on the ...
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Is JWST's weak link the Cryocooler for the MIRI instrument?
While most of JWST uses passive cooling to get instruments to low operating temperature the MIRI requires active measures to get to 7K. I've been reading about the complex system developed to cool ...
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How do satellite motors keep themselves cool and lubricated?
I'm a high-schooler and today we were taught about the car engines and we were told that in order to maintain proper lubrication in order to reduce the heating effect of friction in the pistons using ...
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How long can astronauts wearing Dragon capsule suits walk around unconnected to water coolers?
At various moments in the NASA video NASA’s SpaceX Crew-3 Astronauts Launch to the Space Station astronauts are shown standing or walking or otherwise posing for the camera in their Dragon capsule ...
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How can back shield of JWST be 85-100 degrees Celsius hot if it will be in Earth's shadow?
I have heard, that back shield of James Webb space telescope will be as hot as 85-100 degrees of Celsius.
But how can it be, if it will be in Earth's shadow in L2?
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Decomposing HTP through regenerative cooling for use in closed expander cycle
HTP or high test peroxide has a long history as a low cost and high reliability oxidiser, and has had a lot of recent attention for its pseudo hypergolic nature when passed over a catalyst bed. ...
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Using coolant as 3rd propellant
Rocket engines often have 2 propelants, one of which is used to cool the engine and after that the hot propellant is injected in the combustion chamber.
Would make sense to have a third propellant ...
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Is Geothermal Cooling on Venus Possible?
Would geothermal type cooling be possible for a stationary base on the surface of Venus?
Would the subsoil temperature of Venus hotter or cooler than the atmospheric temperature? (464C / 867F average ...
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Why does ISS uses liquid ammonia in the Active Thermal Control System?
I saw this today and it made me very curious.
See page 8 here: https://www.nasa.gov/pdf/167129main_Systems.pdf
Ammonia has a boiling point of -30 C.
The ammonia is liquid in these loops, so if ever ...
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Cooling the nozzle extension of a nuclear salt water rocket (NSWR)
The nuclear salt water rocket(NSWR) uses a plutonium salt (at least to my understanding) dissolved in water as its fuel. The mixture is kept stable by filling the fuel tank with boron carbide, which ...
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How do pressure-fed engines stay cool?
Does anyone know how pressure-fed/hypergolic rocket engines cool themselves down? Do they regenerativly cool themselves?
Thanks!
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Concerns/challenges with LOX as a regenerative coolant
What are the fundamental issues that make LOX as a regenerative coolant difficult to work with or less ideal than using fuels as a coolant instead in small scale engines (<7000lbs of thrust/ ...
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What is the feasibility of a graphite chamber, nozzle and bell walls
What is the feasibility of using graphite, particularly variants that are easy and affordable to acquire, in a combustion chamber, nozzle and bell as well as nozzle extension? Does it need ...
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What methods have been used to cool aerospikes on paper and in reality?
I am doing a research project and need to mention what methods have been used to cool aerospikes (toroidal is the brute of the paper but I suppose methods for cooking toroidal Aerospikes could apply ...
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Starship fuel temperature at trajectory corrections on it´s way to Mars
There is no problem to use LOX and CH4 at ambient temperature at the many trajectory corrections on it´s way to Mars? I guess that they will not hold cryogenic temperatures so long. I know that the ...
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Cooling an aerospike spike via "fuel diversion"?
My question is, could an aerospike be cooled via diverting a very small quantity of your fuel (fuel used since it has a higher heat capacity than oxidizer and won't, you know, turn your engine into an ...
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Are fans ever used in un-crewed spacecraft?
The question For a Venus bound space probe could could a fan be used to prevent overheating? got me thinking.
Most if not all crewed spacecraft have had fans to move air for one reason or another.
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Could a fan be used to prevent overheating on a Venus bound space probe?
I saw something saying that the circuits on a Venus bound space craft would overheat and basically ruin the the spacecraft.
Is that true?
If so, could they install fans to keep the circuits cool?
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Could Stirling Engines work on sunlight alone?
With the heated side facing the sun and the rest in its own shade, could two contra-rotating Vacuum Stirling Engines and flywheels, in tandem, accumulate torque, to power a reaction wheel? Can the ...
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Why does the Alpha Magnetic Spectrometer (AMS) on the ISS use carbon dioxide for coolant?
Spaceflight Now's Astronauts finish repairs to space station cosmic ray detector says:
Originally designed to operate for just three years, the AMS chalked up eight years of operation before being ...
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Why do many ablative nozzles use phenolic resin and not some other resin?
I am currently looking into ablatively cooled nozzles. Most of the nozzles made out of composite material that I have found use phenol as resin (Space Shuttle Solid Rocket Booster, ARCA Excecutor).
...
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Kerosene engine film cooling
So it is clear that kerosene fueled engines use two fluids for film cooling via injection in the combustion chamber, throat, or nozzle. (That is "true film cooling" and not just a fuel rich outer ring ...
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Do the pipes used for RS-25 nozzle cooling channel have a constant section?
If I understand correctly from this question, The SSME's nozzle is made of pipes into which cool propellant circulate.
The nozzle is larger at the end than near the combustion chamber. Thus, it must ...
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How much could "sublimator operation" have possibly contributed to Apollo 11's "sizable downrange miss"?
This answer to the question Apollo-11 delta-v “due to residual pressure in the docking tunnel pushing the spacecraft apart” detected as it happened? Was it corrected? quotes from the Apollo 11 Mission ...
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How were Apollo spacesuits cooled during simulations/rehearsals on Earth?
The answer and comments to How have space suits dissipated the heat removed from astronauts? explain that the Apollo space suits used the sublimation of ice into the vacuum of space to constantly ...
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Why did the Herschel Space Telescope need helium coolant?
Inspired by answering this question
The Wikipedia entry says this
On 29 April 2013, ESA announced that Herschel's supply of liquid helium, used to cool the instruments and detectors on board, had ...
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Is there any combustion chamber and nozzle cooled with liquid oxygen instead of fuel?
There are many rocket engines for liquid propellants which use the fuel (rocket petrol or liquid hydrogen for instance) to cool the walls of the combustion chamber and the nozzle.
But are there any ...
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Cooling jacket calculation issue [duplicate]
I'm going through How to Design, Build, and Test Small Liquid-Fuel Rocket Engines. The reference explains how to calculate the water flow gap for the cooling jacket that surrounds the combustion ...
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Selection criteria for coolant media on spaceships
What is the selection criteria for coolant media on spaceships? I have read that ammonia as well as water glycol have been used. These two have very diverse properties.
So what makes both of them ...
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what is the temperature of solar panels used in space missions such as ISS
I want to know what is the temperature range of solar panel used in space missions. What is the maximum temperature of solar panels reached in space? How does it affect the efficiency of solar panel? ...