Multi-section carbon ring labyrinth sealing structure of supercritical carbon dioxide turboexpander

Abstract

The invention discloses a multi-section carbon ring labyrinth sealing structure of a supercritical carbon dioxide turboexpander. A sealing cavity is formed among a main shaft of the supercritical carbon dioxide turboexpander, a nozzle ring seat and a nozzle, a shaft sleeve and a plurality of carbon ring sealing assemblies are included, the shaft sleeve adopts an intermittent boss structure, a plurality of spaced grooves are formed between the inner wall surface of the sealing cavity and the boss type shaft sleeve, the multiple carbon ring sealing assemblies with different inner diameters are arranged in the spaced grooves, and the multi-section carbon ring labyrinth sealing structure is formed by carbon ring sealing bodies with different inner diameters for sealing. According to the multi-section carbon ring labyrinth sealing structure of the supercritical carbon dioxide turboexpander, the radial seal and the axial seal are combined, and the corresponding shaft sleeve is processed intothe intermittent boss type, so that sealing gas is prevented from directly overflowing along the smooth shaft sleeve, the gas leakage amount can be reduced, and the effective dynamic seal is realized.

Description

technical field [0001] The invention relates to a carbon ring sealing technology for a turbo expander, in particular to a multi-section carbon ring labyrinth sealing structure for a supercritical carbon dioxide turbo expander. Background technique [0002] Transcritical carbon dioxide power cycle and carbon dioxide Brayton cycle are widely used in the recovery and utilization of nuclear energy, solar energy, geothermal, engine waste heat and industrial waste heat because of their high system efficiency, clean and safe working fluid and good dynamic response. As the core component of the heat-to-power conversion of the carbon dioxide power cycle, the performance of the turboexpander seriously affects the system efficiency. Leakage is a major factor affecting the efficiency of the turbine, especially for supercritical CO with a small flow rate and low power level. 2 Turboexpander effects are particularly severe. For MW and hundreds of kW power level turbine expansion motor se...

AI Technical Summary

Problems solved by technology

[0004] For the through-type carbon ring seal, due to the through-through effect, the gas leakage is large, and part of the kinetic energy cannot be converted into heat energy, thereby affecting production efficiency. Moreover, most of the current labyrinth carbon ring seals have complex structures, and structural modification of the sealing chamber is required. , time-consuming and labor-intensive and the sealing effect is not good

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