Mass Drivers - Revision history

Michel Lamontagne: /* Comparison with rocket launching */

2022-10-19T20:41:54Z

Comparison with rocket launching

2022-10-19T20:26:39Z

Mass driver design

2022-10-19T20:15:57Z

Limitations

2022-10-19T20:01:39Z

Mass driver design

2022-10-19T20:01:13Z

Mass driver design

2022-10-18T17:58:26Z

Developments

2022-10-18T14:35:05Z

Comparison with rocket launching

2022-10-18T14:34:51Z

Comparison with rocket launching

2022-10-18T14:28:36Z

Comparison with rocket launching

2022-10-18T14:27:59Z

Comparison with rocket launching

@@ Line 36: / Line 36: @@
 However, industrial processes are far from 100% energy efficient.  The embodied energy of aluminum is about 210 MJ/kg.  the chemical reaction of the aluminum oxygen rocket Al2+O3 has a ratio of 52(Al) to 48(O) so 1 kg of propellant includes 520 grams of aluminum.  The energy required to produce this aluminum is 110 MJ, or about 28 times the exhaust energy of the propellant.
 Therefore an oxygen-aluminum rocket will require 110 MJ per kg launched and a mass driver 2,4 MJ/kg launched, so '''45 times more energy is required for a rocket'''.
-*Actual results for aluminum-oxygen rockets were a disappointing 1400 m/s.  This would put the energy required for a rocket at 144 times the energy required for a mass driver.
+*Actual results for aluminum-oxygen rockets were a disappointing 1400 m/s (reference).  This would put the energy required for a rocket at 144 times the energy required for a mass driver.
 ===Limitations===

@@ Line 18: / Line 18: @@
 **With an acceleration of 2g, or 20 km/s the time required is 2000/20 = 100 seconds
 **The power would then be 2,4 MJ/100s = 24 KW/kg.
-**The track length is then: length=1/2*a*t^2 = 20*100*100/2 = 100 000m = 100 km.
+**The track length is: length=1/2*a*t^2 = 20*100*100/2 = 100 000m = 100 km.
 *For cargo at 20g
 **With an acceleration of 20g, or 200 km/s the time required is 2000/200 = 10 seconds
 **The power would then be 2,4 MJ/10s = 240 KW/kg.
-**The track length is then: length=1/2*a*t^2 = 200*10*10/2 = 10 000m = 10 km.
+**The track length is: length=1/2*a*t^2 = 200*10*10/2 = 10 000m = 10 km.
 *For cargo at 200g
 **With an acceleration of 200g, or 2000 km/s the time required is 2000/2000 = 1 second
 **The power would then be 2,4 MJ/1s = 2400 KW/kg.
-**The track length is then: length=1/2*a*t^2 = 1000*1*1/2 = 500m = 0,5 km.
+**The track length is: length=1/2*a*t^2 = 1000*1*1/2 = 500m = 0,5 km.

@@ Line 43: / Line 43: @@
 *Although the energy use is among the lowest possible, the power required is high, since the launch period is short, and most designs require energy storage systems to operate.
 *Launching on different orbits require different tracks.
 ==Proposals==

@@ Line 19: / Line 19: @@
 **The power would then be 2,4 MJ/100s = 24 KW/kg.
 **The track length is then: length=1/2*a*t^2 = 20*100*100/2 = 100 000m = 100 km.
-*For cargo, 20g
+*For cargo at 20g
 **With an acceleration of 20g, or 200 km/s the time required is 2000/200 = 10 seconds
 **The power would then be 2,4 MJ/10s = 240 KW/kg.
 **The track length is then: length=1/2*a*t^2 = 200*10*10/2 = 10 000m = 10 km.
-*For cargo 100g
+*For cargo at 200g
 **With an acceleration of 200g, or 2000 km/s the time required is 2000/2000 = 1 second
 **The power would then be 2,4 MJ/1s = 2400 KW/kg.

@@ Line 15: / Line 15: @@
 The track length depends on the acceleration used, that in turn depends on the type of payload and the power than can be delivered.
-With an acceleration of 2g, or 20 km/s the time required is 2000/20 = 100 seconds
+*For passengers
-The power would then be 2,4 MJ/100s = 24 KW/kg.
+**With an acceleration of 2g, or 20 km/s the time required is 2000/20 = 100 seconds
 ===Comparison with rocket launching===

@@ Line 66: / Line 66: @@
 ==Developments==
 *The United States Navy has developed electromagnetic acceleration for carrier launched aircraft to replace steam catapults in the newest generation of carriers now being built.   <ref>[http://www.foxnews.com/scitech/2010/12/24/navy-uses-railgun-launch-fighter-jets/?intcmp=related Navy Uses Electromagnets to Launch Fighter Jet]</ref>
-*Magnetically suspended rail cars have reached velocities of xxx
+*Magnetically suspended rail cars have reached velocities of 170 m/s or less than 10% of the velocity required.
 ==See Also==

@@ Line 26: / Line 26: @@
 However, industrial processes are far from 100% energy efficient.  The embodied energy of aluminum is about 210 MJ/kg.  the chemical reaction of the aluminum oxygen rocket Al2+O3 has a ratio of 52(Al) to 48(O) so 1 kg of propellant includes 520 grams of aluminum.  The energy required to produce this aluminum is 110 MJ, or about 28 times the exhaust energy of the propellant.
-Therefore an oxygen-aluminum rocket will require about 3,92/2 * 28 = '''54 times more energy required for a rocket'''.
+Therefore an oxygen-aluminum rocket will require 1100 MJ per kg launched and a mass driver 2,4 MJ/kg launched, so '''45 times more energy required for a rocket'''.
 ===Limitations===