Difference between revisions of "Template:Featured article"

From Lunarpedia
Jump to: navigation, search
(<!--15px|left-->Featured article: Sintered regolith)
(Featured article: Eddy Current Brake to Orbit)
 
(10 intermediate revisions by 2 users not shown)
Line 1: Line 1:
===<!--[[Image:red_ring.png|15px|left]]-->Featured article: [[Sintered regolith]]===
+
===<!--[[Image:red_ring.png|15px|left]]-->Featured article: [[Eddy Current Brake to Orbit]] | 24 October 2019===
[[Image:MLS1_Brick.GIF|160px|left]] Sintered [[regolith]] falls into the category of ceramic materials as sintering is the process most common to ceramics. When bricks are made from clay on Earth, first the bricks are heated long enough and hot enough to drive out the water. Then the heating is increased to cause partial melting or vitrification which results in the edges of adjacent grains being bonded together once they have cooled.  The unmelted particles provide a stable shape and size during the process which involves some shrinkage and a decrease in porosity.
+
[[File:Eddy current concept.png|160px|left]]
 
+
This device is the central feature of a spacecraft carrier that receives spacecraft into orbit as an aircraft carrier receives aircraft that land on its deck. It works by having a long slotted aluminum tube in orbit and having the shuttle vehicle that is launched to orbital altitude enter this slot while the tube is moving by at orbital speed. The shuttle only needs to reach orbital altitude to enter the eddy current brake tube. That can be 10 kilometers on Luna at the perilune, an altitude that can be reached with 188 meters per second mission delta v, including gravity loss, a few seconds maneuvering fuel, and a small safety margin. Magnetic flux from permanent magnets deployed by the shuttle is directed at the walls of the tube causing a repulsive force and a retarding force.<ref>[http://en.wikipedia.org/wiki/Eddy_current_brake ''Eddy current brake'' at Wikipedia]</ref><ref>[https://en.wikipedia.org/wiki/Inductrack ''Inductrack'' at Wikipedia]</ref> By reducing the speed of the shuttle relative to the orbiting aluminum tube, the shuttle is brought up to near orbital speed. Since eddy current braking loses effectiveness at low relative speeds, friction braking is used to give the shuttle the last 18 meters per second to reach orbital speed and match velocity with the aluminum tube. During all the time that the relative speed of the shuttle and the aluminum tube is greater than 18 meters per second, there is no contact between the material of the shuttle and the material of the aluminum tube. ...([[Eddy Current Brake to Orbit|read more]])
Experiments in radiant heating of regolith simulant have been carried out by NASA Johnson Space Center and Lockheed Engineering & Sciences Co.([[Sintered regolith|read more]])
 
 
<DIV style="text-align:right">
 
<DIV style="text-align:right">
 
<SMALL><STRONG>[[Featured articles|See all featured articles]]</STRONG> | [[Talk:Featured_articles|Nominate!]]</SMALL>
 
<SMALL><STRONG>[[Featured articles|See all featured articles]]</STRONG> | [[Talk:Featured_articles|Nominate!]]</SMALL>

Latest revision as of 03:46, 24 October 2019

Featured article: Eddy Current Brake to Orbit | 24 October 2019

Eddy current concept.png

This device is the central feature of a spacecraft carrier that receives spacecraft into orbit as an aircraft carrier receives aircraft that land on its deck. It works by having a long slotted aluminum tube in orbit and having the shuttle vehicle that is launched to orbital altitude enter this slot while the tube is moving by at orbital speed. The shuttle only needs to reach orbital altitude to enter the eddy current brake tube. That can be 10 kilometers on Luna at the perilune, an altitude that can be reached with 188 meters per second mission delta v, including gravity loss, a few seconds maneuvering fuel, and a small safety margin. Magnetic flux from permanent magnets deployed by the shuttle is directed at the walls of the tube causing a repulsive force and a retarding force.[1][2] By reducing the speed of the shuttle relative to the orbiting aluminum tube, the shuttle is brought up to near orbital speed. Since eddy current braking loses effectiveness at low relative speeds, friction braking is used to give the shuttle the last 18 meters per second to reach orbital speed and match velocity with the aluminum tube. During all the time that the relative speed of the shuttle and the aluminum tube is greater than 18 meters per second, there is no contact between the material of the shuttle and the material of the aluminum tube. ...(read more)

See all featured articles | Nominate!