Kepco Nuclear Fuel Co., Ltd.

Korea Nuclear Fuel Co., Ltd.

Electronics and Telecommunications Research Institute

Jin-Sun Kim

Nam-Gyu Park

Kyu-Tae Kim

Jung-Min Suh

Seong-Ki Lee

Kyong-bo Eom

Joon-kyoo Park

Shin-Ho Lee

Il-Kyu Kim

Hyo-Bong Hong

Jin-Seok Lee

Kyeong-lak Jeon

Ki-Sung Choi

Seung-Min Choi

Jae-Chan Jong

Kyong-Bo Eom

Joon-Kyoo Park

Dong-Geun Ha

Kyoung-Joo Kim

Kyeong-Lak Jeon

Joon-hyung Choi

Gyu-Cheol Shin

Jae-Chan Jeong

Chang-Beom Kim

Yoon-ho Kim

Gyu-Choel Shin

Kang-Hoon Kim

Sung-Kew Park

Kyou-seok Lee

Eul-Gyoon Lim

Disclosed herein is an apparatus for imaging nano magnetic particles using a 3D array of small magnets. A field-free region generation apparatus includes a hexahedral housing having an opening formed in the first surface thereof such that a measurement head is inserted into a spacing area, a pair of rectangular-shaped magnets installed respectively on two surfaces facing each other, among four surfaces perpendicular to the first surface of the housing, and a pair of magnet arrays installed respectively on the first surface of the housing and on another surface facing the first surface, each of the magnet arrays including multiple small magnets arranged along the edge of the opening.

Apparatus for generating field-free region, apparatus and method for nano magnetic particle image

Disclosed herein is a nano-magnetic-particle-imaging apparatus, including a measurement head including excitation and detection coils and accommodating a sample bed for a sample including nano magnetic particles; a gradient magnetic field generation unit for generating a magnetic field having a strength equal to or greater than that of the saturation magnetic field of the nano magnetic particles in a spacing area between identical magnetic poles facing each other and forming a field-free region in a portion thereof; a first driving unit for linearly moving the sample bed; a second driving unit for rotating the gradient magnetic field generation unit in a plane; a third driving unit for linearly reciprocating the gradient magnetic field generation unit; and a control unit for applying a signal to the excitation coil, controlling the driving units, and imaging 3D distribution of the nano magnetic particles based on a detection signal output from the detection coil.

Apparatus and method for nano magnetic particle imaging

Disclosed herein are a magnetic-field-generating coil system, an imaging system having the magnetic-field-generating coil system, and a method for operating the imaging system. The method for operating an imaging system includes generating multiple Linear Gradient Fields (LGFs) in respective axial directions by controlling coil currents, and acquiring MRI information or Magnetic Particle Imaging (MPI) information about an object while moving the multiple LGFs by varying the coil currents.

Magnetic-field-generating coil system, imaging system having magnetic-field-generating coil system, and method for operating imaging system

A combination of a top nozzle and a guide thimble of a nuclear fuel assembly and, more particularly, a structure for joining an inner-extension tube, the top nozzle and the guide thimble. When an inner-extension tube head, which is provided as a means for facilitating removal of the top nozzle of the nuclear fuel assembly from the guide thimble, is removed from an inner-extension tube body to separate the top nozzle from the nuclear fuel assembly, the inner-extension tube body is prevented from undesirably rotating, so that the guide thimble and the inner-extension tube body can maintain the joined state.

Combination of top nozzle and guide thimble for nuclear fuel assembly

A joint structure between a top nozzle and a guide thimble of a nuclear fuel assembly and, more particularly, a structure for joining an inner-extension tube, the top nozzle and the guide thimble. When an inner-extension tube head, which is provided as a means for facilitating removal of the top nozzle of the nuclear fuel assembly from the guide thimble, is removed from an inner-extension tube body to separate the top nozzle from the nuclear fuel assembly, the inner-extension tube body is prevented from undesirably rotating, so that the guide thimble and the inner-extension tube body can maintain the joined state.

Disclosed herein is a joint structure between a top nozzle and a guide thimble. The joint structure includes an outer guide post, an inner-extension tube head, an inner-extension tube body, a wedge and the guide thimble. The outer guide post is provided with an external thread formed on a lower end thereof. The inner-extension tube head includes an annular retaining part formed on an upper end thereof. An internal thread is formed on a medial portion of the inner-extension tube head. An external thread is formed on each of upper and lower ends of the inner-extension tube body. A stop protrusion is provided under a lower end of the wedge. The wedge is welded to the inner-extension tube body after the top nozzle has been joined with the guide thimble. A stop protrusion receiving depression is formed in the guide thimble.

Structure of top nozzle for nuclear fuel assembly

Disclosed is a spacer grid assembly with mixing vanes supporting fuel rods of nuclear fuel assemblies and mixing coolant that flows around the fuel rods, and more particularly, a spacer grid equipped with mixing vanes that mix coolant flowing around fuel rods. The spacer grid with hydraulically balanced mixing vane patterns, in the spacer grid equipped with a strip dividing a plurality of unit grid cells and a plurality of springs, protruded in uniform directions of vertical and horizontal directions on a grid surface of the strip and supporting nuclear fuel rods, which includes: a plurality of mixing vanes protruded to the downstream of coolant on an upper end of the inner grid surface, wherein positions and directions of the mixing vanes are formed in regular patterns on the spacer grid. Thus, it can minimize coolant flow induced vibration of the spacer grid by balancing hydraulic load generated by the mixing vanes, around the center of the spacer grids.

Nuclear fuel grid assembly with hydraulically balanced mixing vane pattern

The present invention relates to a top nozzle for a nuclear fuel assembly that has a two-stage elastic section such that a pushing force against the axial movement of the nuclear fuel assembly under normal conditions is optimized and at the same time a suppressing force against a drastic uplifting force of the nuclear fuel assembly under transient conditions is strengthened, and that lowers the elastic coefficients of the springs operating under normal conditions more than those of existing coil springs, thereby providing an optimal pushing force against the nuclear fuel assembly.

Top nozzle for nuclear fuel assembly

The present invention relates to a fuel rod of a nuclear fuel assembly having a vase-like compression spring adapted to increase the internal volume thereof wherein when the vase-like compression spring is inserted into a cladding tube, it has a relatively smaller volume occupied inside the fuel rod when compared with the existing coil type compression spring, such that the vase-like compression spring can ensure a sufficient space portion receiving the fission gases generated during the operation of the fuel rod, thereby increasing the burn-up performance of the fuel rod and the mechanical integrity thereof.

Fuel rod of nuclear fuel assembly

The present invention relates to an anti-fretting wear spacer grid having a plurality of canoe-shaped springs formed thereon, wherein each of the canoe-shaped springs includes: a fuel rod-contacting part having a flat surface having a predetermined longitudinal length so as to have linear contact with the fuel rod; a curved face-connecting part formed on the upper and lower portions of the fuel rod-contacting part; a leg-connecting part formed on the end portion of the curved face-connecting part; and legs each being formed of a plate shape having a predetermined length and connecting the both sides of the leg-connecting part with one unit grid cell surface.

Anti-fretting wear spacer grid with canoe-shaped spring

Disclosed are a bottom spacer grid with a louver on a spring that can filter debris flowed through a channel of a lower end fitting with coolant on the lower end fitting of a nuclear fuel assembly, and can prevent uplift of fuel rods due to coolant, simultaneously. The bottom spacer grid for debris filtering with the louver for preventing uplift of the fuel rods, in the spacer grid equipped with a strip dividing a plurality of unit grid cells and a plurality of springs, protruded in uniform directions of each of vertical and horizontal directions on a grid surface of the strip, having uniform elasticity and supporting a lower end cap of a nuclear fuel rod, which includes: a spring having a plane portion with a predetermined size to contact to an outer circumference of the bottom end cap of the nuclear fuel rod; a louver protruded downward the spacer grid at a predetermined angle from the plane portion of the spring; and a debris filtering member bent and protruded to the bottom of the grid surface of the spacer grid.

Growing community of inventors

Daejeon, South Korea

Jin-Sun Kim