MadSci Network: Physics

Re: How can MHD provide thrust only by accelerating ions ?

Date: Tue Jan 4 22:08:16 2000
Posted By: Dennis K. Van Gemert, Staff, Flight Design/Performance, The Boeing Company
Area of science: Physics
ID: 945902478.Ph


The link you referenced explains the process with words and graphics.
(http://w “The high pressure, high temperature plasma created by the laser absorption cools and expands out the rear of the vehicle, producing the thrust which propels the lightcraft into the sky.” 

The expansion process appears similar to that of the Linear Aerospike engine ( space/space/propul/RS2200.html).

As for thrust created through accelerating atomic particles (electrons and ions), we only need to look to Newton’s Second Law of Motion: F=ma.  Since electrons and ions have a finite mass, and they are accelerated through a grid, this process produces thrust.  This is also in accordance with the law of conservation of momentum.  Ion propulsion is used as the main propulsion system of Deep Space 1 (  Ion propulsion is far more efficient than chemical propulsion, but provides very low thrust levels ( 1/tech/sep.html).

Current Queue | Current Queue for Physics | Physics archives

Try the links in the MadSci Library for more information on Physics.

MadSci Home | Information | Search | Random Knowledge Generator | MadSci Archives | Mad Library | MAD Labs | MAD FAQs | Ask a ? | Join Us! | Help Support MadSci

MadSci Network,
© 1995-2000. All rights reserved.