NUCLEAR REACTOR FOR VEHICLES Russian patent published in 1996 - IPC

FIELD: nuclear engineering; spacecraft nuclear reactors. SUBSTANCE: reactor core is divided into two subcores which are mounted in tandem on reactor longitudinal axis; one of subcores is subcritical and spaced from other subcore at distance ranging within values of which maximum is chosen from inequality , where Dcore is diameter of cores, sq.m; π is pi number equal to 3.14; Fact. is multiplication factor of neutrons in critical subcore; Pn is return probability of neutrons formed in critical subcore and those returned to subcritical subcore; minimum value is chosen from set of inequalities , where S is neutron density at end of critical subcore in power condition (m^-3s^-1); K_∞ is subcritical subcore multiplication factor; P is leakage probability of neutrons produced in critical subcore through gap between subcores; Q.h.r. is permissible power of heat-removal system in subcritical subcore in power condition, W; Fact. is effective multiplication factor of critical subcore in shutdown state; Σ^k is material neutron absorption macrosection between ends of subcores, (m^-1); Σ_fuel is fissionable material absorption macrosection in subcritical subcore, (m^-1); ΔK_s.s. is safety system efficiency in reactor subcritical subcore; Σ_a is subcritical subcore absorption macrosection, (m^-1); γ_fuel is nuclear concentration of fissionable material in subcritical subcore, (m^-3). EFFECT: reduced cost of reactor and facilitated manufacture along with reduced size and mass of reactor and vehicle as a whole; facilitated transfer from one operating condition of vehicle to other and provision for operation in two modes; reduced effect of high temperatures and vacuum on reactor components. 7 cl, 1 dwg