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In the Glucose topic, kbd512 reminded us that water is an excellent propellant shipping carrier.
This topic is available for forum members who would like to add content, provides links, or to comment on the advantages and disadvantages of the method.
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If you're going to spend the money to process fuels, on-orbit, then LOX/LH2 is the best performer by a significant margin, because the lightest molecule (H2O), is being thrown out the back of the rocket nozzle at a greater velocity than heavier combustion products. H2O is also storable and far cheaper than Glucose.
Edit:
The Energy and Fuel Data Sheet, by Iain Staffell, University of Birmingham, UK
Last edited by kbd512 (Today 16:40:51)
Everyone will understand that water as a propellant shipping method requires equipment able to consume LH2 and LOX.
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Yes, shipping water is a good supply, but it requires a ship that can land it without error and to get most of the rocket it's going to need to be unmanned and ion drive in a slow cargo transit.
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Water: molar mass 18. Hydrogen is 1/9th total mass or 11%.
Ammonia: molar mass 17. Hydrogen is 3/17 total mass or 17.65%.
Methane: molar mass 16. Hydrogen is 4/16 total mass or 25%.
"Plan and prepare for every possibility, and you will never act. It is nobler to have courage as we stumble into half the things we fear than to analyse every possible obstacle and begin nothing. Great things are achieved by embracing great dangers."
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For Calliban re #4
Thank you for your contribution to the topic!
By shipping rocket propellant in the form of water, the shipper provides everything the customer needs to make propellant.
One ton of water yields one ton of propellant.
Furthermore, water is a liquid or a solid at all temperatures of interest in the scenario of interest.... a shipment to Mars, LEO, the Moon or anywhere in the Solar System.
Methane can be shipped in the form of glucose, with the oxygen bundled in the package. We have a topic for shipment of methane as glucose.
Ammonia is a compound I know less about, so am not sure if we should have a topic about a compound made with ammonia that is suitable for shipment in the scenario of interest ....
The scenario of interest is ballistic launch of the propellant.
If you think Ammonia is suitable for consideration for this purpose, please create a topic dedicated to Ammonia as a shipping method.
One definite advantage of Ammonia is that it carries Nitrogen along, and Nitrogen is most definitely useful at the destination separate from the rocket fuel application.
As a reminder for our readers .... The value of a given shipment method (glucose or water in this case) is dependent upon the customer hardware.
If the customer has machinery that consumes methane, then glucose is the better choice.
If the customer has machinery that consumes hydrogen, then water is the better choice.
It may be helpful to stipulate that the shipment package must be able to withstand acceleration measured in the thousands of G's, so the more able the substance is to sustain it's own shape, the better.
In other words, a solid would appear to be a better choice for this purpose than a liquid or gas.
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