CN201066596Y - Down pipe base for nucleus fuel component - Google Patents

Abstract

The utility model relates to a nuclear-fuel component lower tube support, in particular relates to a nuclear-fuel component lower tube support that is used for the simulated experiment. The nuclear-fuel component lower tube support comprises a shell with a square external cross section and a circular internal cross section, the inner cavity of the lower tube support is provided with a worm-gear blade, a core and a signal detection component, the lower end of the lower tube support is provided with a projected lower supporting leg, and a connecting hole is arranged at the upper exist of the lower tube support. The utility model realizes the combinational design of the lower tube support and the worm-gear flow-rate meter, thereby enlarging the circulation area of the flow-rate meter, having smaller flowing pressure decrease, satisfying the requirement that the resistant force property of the lower tube support with worm gear and the original lower tube support is the same and guaranteeing the similar shape of the lower tube support with the original model on the structure; the nuclear-fuel component lower tube support can substitute the original model component to measure the allocated factors of the flow-rate in the entire water-force simulated experiment to meet the requirements of the experiment.

Description

Nuclear fuel assembly lower nozzle

technical field

The utility model relates to a lower pipe seat of a nuclear fuel assembly, in particular to a lower pipe seat of a nuclear fuel assembly used for simulation experiments.

Background technique

The overall hydraulic simulation experiment of the reactor is used to verify the design of the reactor, especially whether the core structure meets the thermal-hydraulic requirements. The acquisition of the core inlet flow distribution factor can improve the reliability of the hydraulic design and further improve the thermal-hydraulic characteristics of the reactor. has a very important meaning.

The nuclear fuel assembly is mainly composed of lower nozzles, rod bundles, upper nozzles and other parts. When conducting the overall hydraulic simulation experiment, it is necessary to rationally simplify the complex components so that the model components have the same resistance characteristics as the prototype components. The simulation component consists of the lower tube base (that is, the turbine flowmeter section), the lower tube plate, the rod bundle, the upper tube base connecting plate and the resistance adjustment section. The resistance of each segment is required to be the same as that of the prototype component, so the lower tube base of the model component must be the same as the prototype The resistance of the tube socket under the assembly is consistent. If an embedded turbine flowmeter is used, the total resistance of the flow in the lower tube base section will include two parts: the resistance of the lower tube base cavity and the resistance of the turbine flowmeter. Since the turbine flowmeter is embedded, the effective flow area of the flowmeter is limited Due to the limitation of the outer dimension of the lower pipe seat, its design value is small, forming a large flow resistance, so that the sum of the cavity resistance of the embedded turbine flowmeter and the lower pipe seat is greater than the resistance of the prototype lower pipe seat, which cannot be realized Simulation of equal resistance. Based on the above specific technical requirements, it is necessary to improve the lower nozzle and turbine flowmeter to reduce their resistance, so as to meet the experimental requirements of the overall hydraulic simulation of the reactor.

Contents of the invention

The purpose of the utility model is to provide a nuclear fuel assembly lower nozzle which satisfies the requirements of the simulation experiment and has the function of flow measurement.

The technical solution for realizing the purpose of the utility model: a lower tube base of a nuclear fuel assembly, including a shell with a square outer section and a circular inner section. The lower end of the tube base is provided with protruding lower supporting feet, and the outlet of the upper end of the lower tube base is provided with a connecting hole.

As mentioned above, the lower nozzle base of the nuclear fuel assembly has four lower support legs in the shape of a pentagon, which are integrated with the lower nozzle housing.

The effect of the utility model is that: when designing the model of the nuclear fuel assembly, the turbine blades, the core and the signal detection assembly are installed in the inner cavity of the lower pipe seat, so that the combined design of the lower pipe seat and the turbine flowmeter is realized, and the circulation of the flowmeter is enlarged. Area, with a small flow pressure drop, to meet the requirements of the same resistance characteristics of the lower pipe seat after the turbine is installed and the lower pipe seat of the prototype assembly, and structurally ensure the shape of the lower pipe seat of the model assembly and the lower pipe of the prototype assembly Similar to the seat, it can replace the prototype component in the overall hydraulic simulation experiment to measure the flow distribution factor and meet the requirements of the experiment.

Description of drawings

Fig. 1 is the front view of the lower socket of the nuclear fuel assembly of the present invention;

Fig. 2 is a top view of the lower socket of the nuclear fuel assembly of the present invention;

Fig. 3 is a bottom view of the lower nozzle of the nuclear fuel assembly of the present invention;

In the figure: 1. Shell; 2. Turbine blade; 3. Movement; 4. Signal detection component; 5. Lower support leg; 6. Connection hole.

Detailed ways

The lower socket of the nuclear fuel assembly suitable for the simulation experiment described in the utility model will be further described below in conjunction with the accompanying drawings.

As shown in Fig. 1, Fig. 2 and Fig. 3, the outer cross-section of the shell 1 of the lower pipe base is square, and the inner cross-section is circular. , The lower end of the lower pipe seat is provided with four protruding lower supporting feet 5, the lower supporting feet 5 are pentagonal, and are integrated with the shell 1 of the lower pipe seat. A connection hole 6 is provided at the outlet of the upper end of the lower pipe seat. The lower tube plate of the lower tube base is put into the connecting hole 6 of the lower tube base through clearance fit. The shape of the entire lower tube seat is similar to the prototype of the lower tube seat that needs to be simulated in the experiment.

According to the requirements of reactor hydraulic characteristics simulation, the design pressure is 1.5MPa, and the design temperature is 80°C. When the fluid passes through the inner cavity of the lower tube base, the fluid pushes the turbine blades to rotate, and then through the magnetic coupling between the turbine blades and the signal detector, the The flow rate of the fluid is converted into an electrical pulse signal output, amplified and shaped by the amplifier, and transmitted to the display instrument to achieve the purpose of measuring the volume flow or total amount of the fluid.

The utility model combines the lower nozzle and the turbine flowmeter structurally, and designs an integrated fuel assembly lower nozzle with flow measurement function, so that the resistance between the lower nozzle after the turbine is installed and the prototype lower nozzle is designed. The characteristics are the same, and the structure is guaranteed to be similar to the prototype lower tube seat, which meets the experimental requirements.

Claims (2)

1. nuclear fuel assembly bottom nozzle, it is characterized in that: described bottom nozzle comprises that outer cross section is square, interior cross section is circular shell (1), the inner chamber of bottom nozzle is equipped with turbo blade (2), movement (3) and input assembly (4), the lower end of bottom nozzle is provided with the lower support pin (5) of projection, and the exit, upper end of bottom nozzle is provided with connecting hole (6).

2. according to the described fuel assembly bottom nozzle of claim 1, it is characterized in that: described lower support pin (5) is pentagon, and is totally four, as a whole with the shell (1) of bottom nozzle.

Images