Patent Number: 
Section: claims

1. A nuclear fuel rod for a fast reactor, comprising:tubular fuel materials comprising a hollow portion formed therein;a tubular inner pipe inserted into the hollow portion of the tubular fuel materials to prevent collapse of the tubular fuel materials due to combustion of nuclear fuel;a tubular cladding pipe which surrounds the tubular fuel materials; anda liquid metal charged in a gap between the tubular fuel materials and the tubular cladding pipe, whereinthe tubular inner pipe comprises a collecting space formed therein to collect fission products which are generated due to combustion of the nuclear fuel,wherein the tubular cladding pipe is formed from stainless steel,wherein the tubular inner pipe is formed from molybdenum (Mo), tungsten (W), niobium (Nb), or tantalum (Ta). 2. The nuclear fuel rod of claim 1, wherein the tubular fuel materials comprises at least one element selected from a group consisting of uranium (U), plutonium (Pu), zirconium (Zr), americium (Am), neptunium (Np), and curium (Cm). 3. The nuclear fuel rod of claim 1, wherein a cross section fraction occupied by the tubular fuel materials takes up 50% to 90% of the total cross section of the fuel rod. 4. The nuclear fuel rod of claim 1, wherein an outer circumference of the tubular inner pipe and an inner circumference of the tubular fuel materials contact each other, so that the tubular inner pipe supports the tubular fuel materials. 5. The nuclear fuel rod of claim 1, wherein the liquid metal is sodium. 6. The nuclear fuel rod of claim 1, wherein the tubular fuel materials are formed by casting metal fuel materials. 7. The nuclear fuel rod of claim 1, wherein the tubular fuel materials are formed by Vibro-packing metal fuel particles.