Entrainment-limit-enhanced super-long gravity assisted heat pipe

Abstract

The invention discloses an entrainment-limit-enhanced super-long gravity assisted heat pipe. The heat pipe comprises an upper sealing end cover, a heat pipe substrate, a lower sealing end cover and asteam-liquid splitting device. The upper sealing end cover, the heat pipe substrate and the lower sealing end cover form an enclosed cavity; the steam-liquid splitting device is disposed in the heat pipe substrate in a sleeved mode; a gap between the steam-liquid splitting device and the heat pipe substrate is a condensate back-flow channel; a center channel of the steam-liquid splitting device isa steam ascending channel; and the steam-liquid splitting device comprises steel cables, a steal cable support and steel cable buckles. The entrainment-limit-enhanced super-long gravity assisted heatpipe is applied to all occasions where the entrainment limits of heat pipes need to be enhanced; in application, ascending steam and descending condensate film are separated by means of a group of steel cables which are distributed nearby the wall surface of the heat pipe enclosed cavity, the shear force of the ascending steam to the descending condensate film is reduced, the entrainment limit ofthe heat pipe is improved, and the advantages of being simple in structure, low in cost, wide in applicability and the like are achieved.

Description

technical field [0001] The invention relates to the field of wellbore gravity heat pipes of oil production wells, in particular to an ultra-long gravity heat pipe with enhanced carrying limit. Background technique [0002] A heat pipe is an efficient heat transfer device that rapidly transfers heat from the hot end to the cold end through the phase change of the internal working fluid. Specifically, when the heat pipe is working, the working fluid absorbs heat and vaporizes at the hot end (evaporation section), and is transported to the cold end (condensation section) under the action of the saturated pressure difference between the hot end and the cold end to condense and release heat. Under the action of force, it flows back to the evaporation section to absorb heat again, so as to realize the circulating flow of working fluid. Gravity heat pipe refers to the heat pipe whose reflux driving force is gravity. [0003] Heat pipes have extremely high equivalent thermal condu...

AI Technical Summary

Problems solved by technology

When the heat pipe is working, the upward-flowing high-speed steam flow and the downward-flowing condensate film form a vapor-liquid counterflow. Under the shear force of the vapor-liquid interface, the liquid film backflow is hindered, which limits the heat transfer capacity of the gravity heat pipe.

(2) Liquid accumulation at the bottom of the ultra-long gravity heat pipe forms a heat transfer dead zone

(3) The steam flow path is long, the resistance is large, and it is difficult to flow to the condensation area

(4) If the heat pipe is too long, the liquid film in the evaporation section may rupture and dry up, reducing the heat transfer performance

This principle should also be applicable to ultra-long gravity heat pipes, but there are technical difficulties and cost constraints in setting coaxial conduits in ultra-long heat pipes

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