In the space of space, where temperatures can dive at less than 455 degrees Fahrenheit, it may seem that keeping things cold would be easy. But the reality is more complex to preserve the propellants of ultra -cold liquid – or fuel – which can easily overheat on -board systems, solar radiation and the exhaust of spacecraft. The solution is a method called Cryogenic liquid management, a series of technologies that stores, transfers and measures super cold fluids for the surface of the moon, Mars and future long -term space flight missions.
Super cold or cryogenic fluids such as liquid hydrogen and liquid oxygen are the most common propellants for spatial exploration. Despite its frightening environment, the space has a “hot” effect on these propellants due to their low boiling points – less than 424 degrees Fahrenheit for liquid hydrogen and approximately less 298 for liquid oxygen – presenting them at risk.
In a primary event of its kind, the Marshall Space Flight Center teams in NASA in Huntsville, in Alabama, test an innovative approach to allow zero -boiling liquid hydrogen storage using two active cooling stages which could prevent the loss of precious propellants.
“Technologies to reduce the loss of propellant must be implemented for successful long -term missions in a deep space such as the Moon and Mars,” said Kathy Henkel, interim director of the NASA Cryogenic Fluids Management Project, based in NASA Marshall. “Two -step cooling prevents loss of propeller and allows long -term storage of propellants, whether in transit or on the surface of a planetary body.”
The new technique, known as “tube on the tank”, incorporates two cryocolores or cooling devices, to maintain cold propellants and thwart several heat sources. Helium, cooled at approximately 424 degrees Fahrenheit, circulates through tubes attached to the exterior wall of the propellant reservoir.
The teams installed the propellant tank in a test stand at NASA Marshall in early June, and the 90 -day test campaign should end in September. The tank is wrapped in a multilayer insulation cover which includes a thin aluminum thermal shield installed between the layers. A second set of tubes, carrying helium at approximately 298 Fahrenheit, is integrated into the shield. This intermediate cooling layer intercepts and rejects the incoming heat before it reaches the tank, which facilitates heat load on the tube system on the tanque.
To avoid an accumulation of dangerous pressure in the propeller’s reservoir in current space flight systems, bouilon vapors must be evacuated, resulting in the loss of precious fuel. The elimination of these losses as propergols is crucial for the success of the most ambitious missions of NASA, including future crew trips to Mars, which will require large amounts of cryogenic propellant in space for months or even years. So far, cryogenic fuels have only been used for missions of less than a week.
“To go on Mars and have a lasting presence, you must preserve cryogens for use as a Rocket or Landder propeller,” said Henkel. “Rockets are currently controlling their margin propellant, where larger tanks are designed to contain more propellant than what is necessary for a mission. Loss of propellant is not a problem with short trips because the loss is taken into account in this margin. However, the missions of human exploration in Mars or longer stays on the Moon will require a different approach because of the very large tanks of which it would be necessary. ”
The Cryogenic Fluid Management Portfolio project is an inter-agencies-based team at NASA Marshall and the agency Glenn Research Center in Cleveland. The work of the cryogenic portfolio is within the framework of the NASA technological demonstration missions program, which is part of the NASA spatial technological mission management, and includes more than 20 individual technological development activities.
Learn more about the management of cryogenic liquid:
Go.nasa.gov/cfm
