Method and system for decelerating pneumatic delivery of pebble bed reactor fuel elements

Abstract

The invention relates to a method and a system for decelerating the pneumatic delivery of pebble bed reactor fuel elements, belonging to the field of the nuclear reactor fuel delivery technology. Along the direction of delivery pipe fuel elements, the equipment or the delivery pipe fuel elements comprise a device for detecting the speed of the ball over the entrance, a front end gas shunt, a middle end gas shunt, a decelerating elbow pipe and a device for detecting the speed of the ball over the exit. A gas flow pipe led out by the front end gas shunt and the middle end gas shunt is provided with a regulating valve and a flow meter. The pneumatic thrust drops suddenly in a fuel element delivering pipe of the system by the drainage of the front end gas shunt, and the pneumatic delivery of the pebble bed reactor fuel elements is decelerated by a pipe mechanical structure. The main control procedure judges the start and the stop of the system through the feedback value of the device for detecting the speed of the ball over the entrance, the device for detecting the speed of the ball over the exit, the regulating valve and the flow meter, calculates and outputs the regulating quantity of the regulating valve and controls the fuel element exit velocity. The system realizes the adjustability of the reduction ratio for the fuel elements of multiple operating conditions, has obvious effect of decelerating the pneumatic delivery of the pebble bed reactor fuel elements and can adapt to the requirements that the pebble bed reactor fuel elements run more reliably and safely.

Description

technical field [0001] The patent of the present invention relates to nuclear reactor fuel delivery technology, in particular to a method and system for pneumatic delivery of pebble bed reactor fuel elements by bypass, diversion, and deceleration. Background technique [0002] The modular high-temperature pebble bed gas-cooled reactor is the fourth-generation new nuclear reactor currently being researched and developed, and is currently recognized as the nuclear reactor type with the highest inherent safety in the world. The most important feature of this reactor-type nuclear fuel element transportation is: relying on the air pressure thrust provided by the pneumatic conveying system or the self-weight of the fuel to realize the fuel element (spherical) circular feeding and unloading. In the external pipeline system of the core, the fuel elements run from the bottom of the core to the top under the push of high-speed airflow. In order to prevent the fuel elements at the out...

AI Technical Summary

Problems solved by technology

The disadvantage of this invention is: this deceleration system is installed inside the reactor pressure vessel, for this reason, a plurality of reverse gas flow introduction and output pipelines need to pass through the boundary of the core pressure vessel, which increases the complexity of the pipeline system structure and equipment maintenance difficulty

In addition, this deceleration system cannot detect the running speed of the fuel element, and the adjustment of the outlet speed of the fuel element is uncertain.

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