Multi Megawatt Power System Analysis Report

Missions to the outer planets or to near-by planets requiring short times and/or increased payload carrying capability will benefit from nuclear power. A concept study was undertaken to evaluate options for a multi-megawatt power source for nuclear electric propulsion. The nominal electric power requirement was set at 15 MWe with an assumed mission profile of 120 days at full power, 60 days in hot standby, and another 120 days of full power, repeated several times for 7 years of service. Of the numerous options considered, two that appeared to have the greatest promise were a gas-cooled reactor based on the NERVA Derivative design, operating a closed cycle Brayton power conversion system; and a molten lithium-cooled reactor based on SP-100 technology, driving a boiling potassium Rankine power conversion system. This study examined the relative merits of these two systems, seeking to optimize the specific mass. Conclusions were that either concept appeared capable of approaching the specific mass goal of 3-5 kg/kWe estimated to be needed for this class of mission, though neither could be realized without substantial development in reactor fuels technology, thermal radiator mass efficiency, and power conversion and distribution electronics and systems capable of operating at high temperatures. Thoughmore » the gas-Brayton systems showed an apparent advantage in specific mass, differences in the degree of conservatism inherent in the models used suggests expectations for the two approaches may be similar. Brayton systems eliminate the need to deal with two-phase flows in the microgravity environment of space.« less

[1]  M. P. Moriarty,et al.  SP-100 advanced radiator designs for thermoelectric and Stirling applications , 1989, Proceedings of the 24th Intersociety Energy Conversion Engineering Conference.

[2]  Ronald J. Lipinski,et al.  Fission-based electric propulsion for interstellar precursor missions , 1999 .

[3]  Lee S. Mason,et al.  A comparison of Brayton and Stirling space nuclear power systems for power levels from 1 kilowatt to 10 megawatts , 2001 .

[4]  F. W. Baity,et al.  THE PHYSICS AND ENGINEERING OF THE VASIMR ENGINE , 2000 .

[5]  Michael Schuller,et al.  Thermionic/AMTEC cascade converter concept for high-efficiency space power , 1997 .

[6]  F. C. Difilippo.  Nuclear modules for space electric propulsion , 1998 .

[7]  Glen Reed Longhurst,et al.  Multi-Megawatt Power System Trade Study , 2002 .

[8]  R. Pruschek,et al.  The Modular High-Temperature Reactor , 1985 .

[9]  Philip R. Pluta,et al.  SP-100 multimegawatt scaleup to meet electric propulsion mission requirements , 1991 .

[10]  R.B. Harty,et al.  Applications of Brayton cycle technology to space power , 1994, IEEE Aerospace and Electronic Systems Magazine.

[11]  M.A.K. Lodhi,et al.  Effect of geometrical variations on AMTEC cell heat losses , 2000 .

[12]  J. R. Wetch.  Megawatt Class Nuclear Space Power Systems (MCNSPS) conceptual design and evaluation report. Volume 3, technologies 2: Power conversion , 1988 .

[13]  Robert S. Holcomb,et al.  Summary and recommendations on nuclear electric propulsion technology for the space exploration initiative , 1993 .

[14]  Mike Houts,et al.  Results of 30 kWt Safe Affordable Fission Engine (SAFE-30) primary heat transport testing , 2001 .

[16]  David Buden,et al.  Space nuclear power , 1985 .

[17]  Alfred Schock,et al.  Design and performance of radioisotope space power systems based on OSC multitube AMTEC converter designs , 1997, IECEC-97 Proceedings of the Thirty-Second Intersociety Energy Conversion Engineering Conference (Cat. No.97CH6203).