Study on Specific Mass of Nuclear Electric Propulsion System with Closed Cycle MHD Generator

Abstract

In space, radiation dose to crew increases in proportion to a increase of flight-time. High radiation dose to human have an influence on human health. Therefore, propulsion system that can minimize in-flight time is required. In the present study, to minimize in-flight time, nuclear electric propulsion system (NEP system) is suggested for human exploration to Mars. NEP system consists of CCMHD power generation system driven by nuclear fission reactor (NFR) providing electric power to the propulsion system and the variable specific impulse magneto-plasma rocket (VASIMR ® ). In this study, modeling of power plant for NEP system and system analysis of it is carried out. Then Parameter are changed, the outlet temperature of NFR, the radiator temperature and the enthalpy extraction of MHD generator, in order to know how to minimize specific mass In the outlet temperature of NFR change, specific mass of NEP system decreases with an increase of outlet temperature of NFR. In the radiator temperature change, specific mass of NEP system have minimum point in radiator temperature. In the enthalpy extraction of MHD generator, specific mass of NEP system have minimum point in enthalpy extraction. Specific mass of NEP system less than ] / [ 2 kWe kg system   could be expected. Nomenclature system  = specific mass of the propulsion system rad  = mass per unit area of the radiator  = specific heat ratio  = emissivity of radiator  = the Stefan-Boltzmann constant co  = isentropic efficiency of compressor MHD  = isentropic efficiency of MHD generator rad A = radiator area . .E E = enthalpy extraction of MHD generator p C = specific heat m  = mass flow rate of working medium n = compressor number ico P = inlet pressure of compressor 2 iMHD P = inlet pressure of MHD generator oco P = outlet pressure of compressor oMHD P = outlet pressure of MHD generator eMHD Q = electric power from MHD generator ex Q = exchange power in regenerator ico Q = inlet thermal power of compressor ilre Q = inlet thermal power of low temperature side of compressor iMHD Q = inlet thermal power of MHD generator oco Q = outlet thermal power of compressor ohre Q = outlet thermal power of high temperature side of compressor oMHD Q = outlet thermal power of MHD generator or Q = outlet thermal power of nuclear thermal reactor rad Q = waste thermal power from radiator wco Q = compressor power ex T = temperature difference in regenerator iMHD T = inlet temperature of MHD generator ihre T = inlet temperature of high temperature side of compressor olre T = outlet temperature of low temperature side of compressor oMHD T = outlet temperature of MHD generator or T = outlet temperature of nuclear thermal reactor rad T = radiator temperature rad M = radiator mass system M = NEP system mass pro Q = thermal power of propulsion system

Taguchi parametric analysis of the effects of electrode and magnetic actuator characteristics on Lorentz forces and heat transfer of a weak low-profile magneto-hydrodynamic blanket propulsion system

“…6 Also, the term ''magnetohydrodynamics'' was first proposed by Alfven in 1941. 7 Magneto-hydrodynamics has been and is still used in many fields including astrophysics, 8,9 MHD generators and pumps, 10,11 metallurgy, 12,13 fusion reactors, 14,15 nanotechnologies, 16,17 flow control, 18,19 and aerospace 20 and marine 21,22 propulsion systems. In the field of marine propulsion, perhaps one of the first related patents and manuscripts dates back to 1960s.…”