Decompression empty sun protection plug-in type heat-tube vacuum heat collecting element
Technical field
The present invention relates to decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.
Background technology
Vacuum heat collection pipe arranges vacuum heat-insulating layer between its cover glass tube and inner glass tube, can manufacture the vacuum solar water heater that winter also can provide domestic hot-water.With the solar water heater of heat-pipe vacuum heat collecting pipe manufacture have more anhydrous Energy Efficiency Ratio in pipe high, meet safe drinking water standard, single tube damages the advantage such as in the same old way to work.Therefore.In pipe, anhydrous solar energy evacuated water-both with hot pipe will likely capture the increasing market share.
Adopt integrated glass heat pipe to have can to melt with cover glass tube seal, glass heat pipe surperficial can directly make absorbing film heat transfer link few, the splendid water of thermophysical property can be adopted to make the advantages such as working medium.
But during air drying, heat collecting element inside heat pipe temperature can reach 230 DEG C, saturated vapor pressure corresponding to this temperature is 28.53 atmospheric pressure, and ratio and the working medium volumetric ratio of corresponding working medium filling weight and heat pipe volume are 1.1%, and namely every 1 liter capacity has 11 ml waters.
The pressure of inside heat pipe when can reduce air drying by reducing working medium filling weight, for device of working medium: when working medium filling weight/heat pipe volume rate is reduced to 2 milliliters/1000 milliliters from 0.5% when 5 milliliters/1000 milliliters 0.2%, correspondingly its highest saturated vapor pressure is reduced to about 3.7 atmospheric pressure of 140 DEG C from about 10 atmospheric pressure of 180 DEG C, and when inside heat pipe continues to be warming up to 180 DEG C from 140 DEG C about 3.7 atmospheric most high-vapor-pressures, internal pressure only has 4 atm higher.But working medium filling weight can not only decide with internal pressure during air drying sometimes.For a working medium filling weight/heat pipe volume rate be 0.2%, the heat pipe of internal capacity 1000 milliliters, length 2000 millimeters, if be no more than 4 atmospheric pressure, then working medium filling weight about 1.8 milliliters in order to internal pressure when making air drying 230 DEG C.Even if problem is described heat pipe is light-pipe structure, when tilting about 45 degree of work, the condensed water of cold junction, the circulating water in hot junction add that the water yield 0.353 milliliter of sum of 85 DEG C of water vapours can far more than 1.8 milliliters.
Normally work to meet heat pipe and make working medium filling weight/heat pipe volume rate be greater than 0.2% even 0.3%, and guarantee glass heat pipe not because air drying and bombing, empty sun protection measure must be taked.
Chinese invention patent 2009101951003 anti-air drying all-glass vacuum heat collector tube element; disclose a kind of empty sun protection all-glass vacuum heat collector tube element; form by arranging controlled heat transfer path between vacuum heat collection element absorber and cover glass-tube; controlled heat transfer path is made up of movable heat transfer piece and actuator, it is characterized in that the heating power transducing actuator containing being connected with vacuum heat collection element absorber low thermal resistance.Because this patent is not special in gravity assisted heat pipe heat collecting element, thus specific aim is not strong; The uniformity of the original product of bimetal leaf heating power transducing actuator that it adopts is just bad, after repeatedly temperature distortion, restorable ability can reduce again, 20 year projected life that operating point setting, control variables that its control system born is correlated with input, compare, transducing and Power supply and n-back test far can not normally effectively work because precision is affected heat collecting element is possible.
Fig. 4 provides the light-pipe structure gravity assisted heat pipe structural representation of a tiltably-mounted.
In Fig. 4, heat pipe 1 is made up of shell and internal working medium.Its operation principle is: heat energy hot junction from below namely side by side inwards arrows place input, the working medium at heat pipe 1 inner bottom place is heated vaporization, steam is under the effect of pressure reduction, upwards advance to heat pipe cold junction and arrow side by side outwards marked position release heat energy and be supplied to load and be condensed into liquid and be back to cold junction below under gravity, again to be heated vaporization in hot junction working medium ..., constantly circulation realizes two phase flow heat transfer circulation thus.Heat pipe has excellent heat-transfer capability, heat flow density ability to transform and isothermal characteristics.If heat pipe 1 hot junction inputs 100 watts, then the output of its cold junction is the highest can reach 97 watts even higher.
If attempt only to input heat energy from below to the heat pipe 1 of Fig. 4, and do not take heat energy away, then heat pipe 1 steam inside pressure can sharply rise.If heat pipe 1 adopts water as working medium and abundant, then, when heat pipe 1 temperature reaches 230 DEG C, inner maximum pressure can reach 28.53 atmospheric pressure.
If attempt the heating from taking out heat energy a little more than heat pipe 1 bottom local a section of whole heat pipe 1 length 3% of accounting for for example from bottom comprehensively from top to bottom of the heat pipe 1 of Fig. 4 below, namely only make bottom account for the position of heat pipe 1 total length 3% forward simultaneously as overlapping cold junction, then the vapour pressure of heat pipe 1 inside can drop to the saturated vapor pressure corresponding with the temperature of cold junction below.When for example using water as working medium, keep the temperature 100 DEG C of overlapping cold junction below heat pipe 1, even if then other parts are heated to 230 DEG C above, because the liquid refrigerant of heat pipe 1 inside is all collected in described overlapping cold junction, heat pipe 1 hot junction above except described overlapping cold junction is whole dry owing to not having working medium to supplement, and two phase flow heat transfer mechanism has not existed.The steam pressure of heat pipe 1 inside is also only had an appointment 1 atmospheric pressure.
An example of overlapping cold junction be thermotube wall with absorbing film, absorb sunshine and input as heat energy, connect described thermotube wall with Thermal Conduction Equipment low thermal resistance and by heat energy transfer simultaneously.
This make that heat pipe 1 is in tilted layout, heat energy inputs above heat pipe 1 and only with below a bit of design as overlapping cold junction perhaps there is no what meaning in other occasions, but for the empty sun protection of solar collection element, because only need minimum a part of heat radiation power---when this part heat radiation power is used for guaranteeing that air drying occurs, the peak that empty sun protection device starts the initial stage inside heat pipe vapour pressure worked is no more than setting value; This part heat radiation power is also greater than the heat energy input power of described overlapping cold junction as hot junction---thus have radiating element volume compact, dependable performance, heat radiation power little, on the venting of vacuum heat-insulating layer less, on absorber to block impact little and heat collecting element tail end can be utilized as the advantage of heat dissipation interface.
Can see, the heat radiation power required for less, the described empty sun protection device of the area of overlapping cold junction is also less, more favourable.Actual heat collecting element needs the device of tail box and so on to settle.Tail box can hide the tail end of heat collecting element.Overlapping cold junction is not belonged to by the part that tail box hides.Why also can use overlapping cold junction; be because some heat collecting element empty sun protection device be relatively applicable to being installed on vacuum heat-insulating layer drum-shaped section or; heat collection element cover glass pipe is with necking segment and be adopt to assemble inner glass tube after necking segment is formed, and then draws tail pipe to be called for short the technique of post-tensioning tail pipe to cover glass tube circle envelope.If the round end-blocking that post-tensioning tail pipe technique is formed is not suitable for heat radiation, just needs utilization is dispelled the heat from described round end-blocking cover glass tube drum-shaped section up.The heat pipe corresponding with described drum-shaped section or inner glass tube end section belong to overlapping cold junction.
China's 912050845 utility model electric cooker automatic magnetic temperature detect switch (TDS)s, describe one and utilize pyromagnetic force inverting element operation principle.
Summary of the invention
The object of the invention is to provide decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.
The present invention solves one of technical scheme that its technical problem takes: in the vacuum heat-insulating layer of an all-glass vacuum heat collector tube element tail end, arrange an empty sun protection device; connect a plug-in type heat pipe at the inner glass tube internal chamber wall low thermal resistance of all-glass vacuum heat collector tube element, form a decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.All-glass vacuum heat collector tube element cover glass tube and inner glass tube nested, concentric arrange that sealing-in is made.Described heat collecting element is vertical or tilt to install, and described heat pipe relies on gravity work.Empty sun protection device comprises one and passes hot linked thermodynamic-driven device with inner glass tube tail end and be in transmission connection with thermodynamic-driven device or the heat straight-tube integrally manufactured with thermodynamic-driven device.Described empty sun protection device has two kinds of stable states: heat straight-tube stretches out unlatching heat conduction state during heat transfer connection cover glass tube tail end; The closedown adiabatci condition that heat straight-tube retraction is not conducted heat when connecting cover glass tube tail end.Described thermodynamic-driven device comprises thermal sensitive permanent magnetic steel driving element, bimetallic strip driver part, one of memory alloy actuator part and bellows driving element.Described thermal sensitive permanent magnetic steel driving element comprises one piece of thermal sensitive permanent magnetic steel and one block of soft iron; Thermal sensitive permanent magnetic steel is connected with inner glass tube low thermal resistance by thermal conductance; Containing shadow shield above thermal sensitive permanent magnetic steel; Soft iron is tied and can moves forward and backward along heat collecting element direction of axis line and be in transmission connection by transmission steel wire and heat straight-tube.Directly or by a heat sink secondary low thermal resistance of one-dimensional movement be connected between heat straight-tube with inner glass tube tail end.Heat straight-tube can move forward and backward along heat collecting element direction of axis line; Outer end shape and the cover glass tube tail end inner surface of heat straight-tube match.
The present invention solves the technical scheme two that its technical problem is taked: in the vacuum heat-insulating layer of all-glass vacuum heat collector tube element tail end, arrange a boosting empty sun protection device; connect a plug-in type heat pipe at the inner glass tube internal chamber wall low thermal resistance of all-glass vacuum heat collector tube element, form a boosting decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.All-glass vacuum heat collector tube element cover glass tube and inner glass tube nested, concentric arrange that sealing-in is made.Described heat collecting element is vertical or tilt to install, and described heat pipe relies on gravity work.Boosting decompression empty sun protection device comprises one and passes hot linked boosting thermodynamic-driven device with inner glass tube tail end and be in transmission connection with boosting thermodynamic-driven device or the heat straight-tube integrally manufactured with boosting thermodynamic-driven device.Boosting empty sun protection device has two kinds of stable states: heat straight-tube stretches out unlatching heat conduction state during heat transfer connection cover glass tube tail end; The closedown adiabatci condition that heat straight-tube retraction is not conducted heat when connecting cover glass tube tail end.Directly or by a heat sink secondary low thermal resistance of one-dimensional movement be connected between heat straight-tube with inner glass tube tail end.Heat straight-tube can move forward and backward along heat collecting element direction of axis line; The outer end shape of heat straight-tube and matching of cover glass tube tail end inner surface.Described boosting thermodynamic-driven device comprise thermal sensitive permanent magnetic steel soft iron drive to bimetal leaf boosting parts.Thermal sensitive permanent magnetic steel soft iron drives comprising one piece of thermal sensitive permanent magnetic steel and one block of soft iron.Thermal sensitive permanent magnetic steel is connected with inner glass tube or heat pipe hot junction low thermal resistance by one piece of thermal conductance.Containing shadow shield above thermal sensitive permanent magnetic steel.Soft iron is tied and can does along the movable of heat collecting element direction of axis line and be in transmission connection by transmission steel wire and heat straight-tube.Described thermal sensitive permanent magnetic steel soft iron drive to containing and the linkage interface of bimetal leaf boosting parts.Described bimetal leaf boosting parts from loss of excitation state to the temperature-fall period having magnetic state to change in thermal sensitive permanent magnetic steel, produce deformation and help to promote the driving of thermal sensitive permanent magnetic steel soft iron to adhesive.
Cover glass tube tail end inner surface low thermal resistance can also be made to connect a heat radiation paster.
Heat radiation paster can also be made to be connected with adopting jump ring high thermal resistance between heat sink; Or be connected by a jump ring high thermal resistance with inner glass tube tail end inside cover glass tube tail end.
Described heat collecting element tail end can also be made to be the part being no more than heat collecting element total length 6% from heat collecting element tail end bottom outer surface forward.
Beneficial effect of the present invention: the present invention's empty sun protection plug-in type heat-tube vacuum heat collecting element that reduces pressure adopts and collects liquid refrigerant in heat pipe hot junction bottom end, the empty sun protection design blocking inside heat pipe two phase flow heat transfer in the heat radiation of heat pipe bottom end, and heat radiation power can reduce greatly.Citing: one exports the heat collecting element of 70 watts, working medium filling weight 3 milliliters.Adopt the technical scheme preventing heat pipe bombing in the uniform controlled heat transfer path heat radiation of heat pipe hot end surface, the heat radiation power of controlled heat transfer path is 40 watts, inside heat pipe temperature is the highest also has more than 150 DEG C, and corresponding water vapor pressure still can reach the voltage endurance capability that 4.8 atmospheric pressure exceed external diameter 58 millimeters, wall thickness 1.8 millimeters of inner glass tubes.The present invention is for the same heat collecting element exporting 70 watts, and decompression empty sun protection heat transfer path only needs 10 watts of heat radiation powers, just can carry out the water of heat absorbing glass inside heat pipe with the speed of 0.25 ml/min when air drying occurs.After air drying starts about 6 minutes, although the temperature of plug-in type tube surface raises about 30 DEG C at that time, inside, heat pipe hot junction except bottom end all dry, vapour pressure be less than 1.5 atmospheric pressure.The heat radiation power saving 30 watts makes cost have larger reduction, reduce heat transfer path to the venting 75% of vacuum heat-insulating layer and reliability increase substantially.Key is the bombing problem that effectively can solve major diameter glass heat pipe.The present invention adopt a small-power empty sun protection device just can ensure plug-in type inside heat pipe water vapor pressure is no more than 2 atmospheric pressure all the time, and do not affect the normal work of heat collecting element completely.
Heat straight-tube heat transfer area is large, rigidity strong, it is few to utilize heat collecting element bottom to build the absorption resource occupation of heat transfer path to heat collecting element.
Thermal sensitive permanent magnetic steel driving element uniformity is good, reproducible, control accuracy is high, long service life, performance are satisfactory.
Accompanying drawing explanation
Below in conjunction with drawings and Examples, the present invention is further described.
Fig. 1 is that a boosting decompression empty sun protection plug-in type heat-tube vacuum heat collecting element faces structural representation.
Fig. 2 is TV structure schematic diagram on a boosting decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.
Fig. 3 is that Fig. 1 looks sectional structure schematic diagram on the left side at heat straight-tube 7 place.
Fig. 4 is the light-pipe structure gravity assisted heat pipe structural representation of a tiltably-mounted.
Fig. 5 is the expanded view of a slice heat straight-tube.
Fig. 6 is an all-glass vacuum solar energy collection tube structural representation.
1. heat pipes in figure; 2. cover glass tube; 3. inner glass tube; 4. dispel the heat paster; 5. heat sink; 6. boosting thermal sensitive permanent magnetic steel driving element; 7. heat straight-tube; 8. thermal sensitive permanent magnetic steel; 9. soft iron; 10. bimetal leaf boosting parts; 11. thermal conductances; 12. shadow shields; 13. plate washers; 14. transmission steel wires; 15. springs; 16. connecting plates; 17. four paws jump rings; 18. square holes; 19. breach.
Detailed description of the invention
Fig. 1, Fig. 2 and Fig. 3 provide one embodiment of the invention.
In Fig. 1 to 3; a boosting empty sun protection device is set in the vacuum heat-insulating layer of an all-glass vacuum heat collector tube element; connect a plug-in type heat pipe 1 at the inner glass tube 3 internal chamber wall low thermal resistance of all-glass vacuum heat collector tube element, form a boosting decompression empty sun protection plug-in type heat-tube vacuum heat collecting element.All-glass vacuum heat collector tube element cover glass tube 2 and inner glass tube 3 nested, concentric arrange that sealing-in is made.Boosting empty sun protection device comprises heat radiation paster 4, heat sink 5, boosting thermal sensitive permanent magnetic steel driving element 6 and heat straight-tube 7 and forms.The shape of heat radiation paster 4 outer surface and the shape of cover glass tube 2 tail end inner surface match.Heat radiation paster 4 thickness 0.22 millimeter, width 40 millimeters.Heat radiation paster 4 jump ring overlays in cover glass tube 2 inwall.Heat sink 5 thickness 0.22 millimeter, width 40 millimeters.Boosting thermal sensitive permanent magnetic steel driving element 6 comprises one piece of thermal sensitive permanent magnetic steel, 8, one block of soft iron 9 and bimetal leaf boosting parts 10; Thermal sensitive permanent magnetic steel 8 is connected with inner glass tube 3 low thermal resistance by thermal conductance 11; Thermal sensitive permanent magnetic steel 8 containing shadow shield 12, prevents the thermal sensitive permanent magnetic steel 8 that sunshine direct projection is being in vacuum heat-insulating layer from making its misoperation above.Soft iron 9 can be moved forward and backward along heat collecting element direction of axis line by both sides plate washer 13 constraint and is in transmission connection by transmission steel wire 14 and heat straight-tube 7, and soft iron 9 pushed away from permanent-magnet steel 8 by spring 15 thrust or has the trend pusheding away from permanent-magnet steel 8.As the linkage interface with bimetal leaf boosting parts 10 free end in the middle of outside soft iron 9.The stiff end of bimetal leaf boosting parts 10 is connected with plate washer 13.Heat straight-tube 7 thickness 0.22 millimeter, width 40 millimeters.Adopt one-dimensional movement auxiliary structure low thermal resistance to be connected between heat straight-tube 7 with heat sink 5, heat straight-tube 7 can be stretched out to retract along heat collecting element direction of axis line and be moved forward and backward.Heat sink 5 is wrapped up low thermal resistance and is connected heat pipe 1 hot junction bottom end and overlay on inner glass tube 3 with jump ring.The outer end shape of heat straight-tube 7 and matching of heat radiation paster 4 inner surface.Thermal conductance 11 thickness 0.22 millimeter, width 20 millimeters, be rolled into tubular.Thermal conductance 11 is connected by a slice connecting plate 16 rigidity high thermal resistance with heat sink 5.Location between cover glass tube 2 and inner glass tube 3 (four paws jump ring for for purpose of brevity, do not draw in Fig. 1,2, but special Fig. 6 illustrates) is realized with being connected by the high thermal resistance of four paws jump ring 17 between inner glass tube 3 tail end inside cover glass tube 2 tail end.
The making material of heat radiation paster 4, heat sink 5, heat straight-tube 7 comprises steel plate, aluminium sheet and copper coin.
The operation principle of Fig. 1 to 3 embodiment: when embedding the heat collecting element normal dip being provided with described decompression empty sun protection device and arranging and be not in air drying state; sunshine is converted to heat energy on inner glass tube absorbing film, and heat energy passes to insertion type glass housing heat pipe 1 internal working medium by inner glass tube and makes it vaporization.Because heat pipe 1 cold junction temperature is lower than 95 DEG C, working substance steam flows to cold junction heat release and condenses into liquid and returns to hot junction under gravity and vaporization of being heated once again under differential pressure action ... so go round and begin again and realize two phase flow heat transfer circulation.
Now; thermal sensitive permanent magnetic steel 8 temperature be connected with inner glass tube 3 low thermal resistance by thermal conductance 11 does not reach loss of excitation temperature; thermal sensitive permanent magnetic steel 8 holds soft iron 9 by heat straight-tube 7 toward Zola, and make heat straight-tube 7 not contact heat radiation paster 4, empty sun protection device is in closedown adiabatci condition.The normal thermal-arrest of heat collecting element.Marginal position when peviform dotted line represents that heat straight-tube 7 is retracted in Fig. 1.
When heat collecting element is in air drying state, thermal sensitive permanent magnetic steel 8 temperature raises magnetic force and disappears, and spring 14 pushes soft iron 9 and heat straight-tube 7 to the right side, and make heat straight-tube 7 stretch out heat transfer and connect heat radiation paster 4, empty sun protection device is in opens heat conduction state.The heat energy in heat pipe 1 hot junction is lost to environment continually by inner glass tube 3 and empty sun protection device.The steam of heat pipe 1 inside flows to bottom end and condenses and be collected in bottom end under differential pressure action, clamps down on heat pipe 1 internal pressure and is in low level all the time, ensures that heat collecting element bombing can not realize the empty sun protection of heat collecting element.Due to the constraint of bimetal leaf boosting parts 10, maximum 2 millimeters of the distance that soft iron 9 moves right, can attract to return by soft iron 9 when after can ensureing like this, thermal sensitive permanent magnetic steel 8 magnetic force recovers once again.
When heat collecting element is in air drying state, temperature its shape high of bimetal leaf boosting parts 10 is not curved left, ensures that soft iron 9 tension moves to right.
Later heat collecting element departs from air drying state, and thermal sensitive permanent magnetic steel 8 temperature reduces magnetic force and recovers and attract soft iron 9 that heat straight-tube 7 is retracted not conduct heat to connect the paster 4 that dispels the heat, and empty sun protection device is in closedown adiabatci condition, and heat collecting element can normally work again.
Bimetal leaf boosting parts 10 from loss of excitation state to the temperature-fall period having magnetic state to change in thermal sensitive permanent magnetic steel 8, produce the deformation intermediate portion soft iron 9 of projection promotion left and are moved to the left (as shown in Fig. 2 mean camber line).Due to the existence of bimetal leaf boosting parts 10; overcome the associated components such as the heat transfer path of the linear expansion coefficient metal manufacture more much bigger than inner glass tube 3 and thermal sensitive permanent magnetic steel driving element 6 because Various Seasonal expand with heat and contract with cold make soft iron 9 from thermal sensitive permanent magnetic steel 8 excessively away from; the problem of the inadequate empty sun protection device cisco unity malfunction of thermal sensitive permanent magnetic steel 8 suction, makes thermal sensitive permanent magnetic steel driving element 6 work more rapid reliable.
Fig. 1 to 3 embodiment is for the all-glass vacuum heat collector tube element of cover glass tube diameter 70, inner glass tube diameter 58, and do not adopt heat radiation paster and heat sink, the heat radiation power of described empty sun protection device also can reach more than 10 watts.
Fig. 5 provides the expanded view of heat straight-tube 7.
In Fig. 5, heat straight-tube 7 is unfolded.Its square hole 18 is established for avoiding four paws jump ring.Breach 19 is for being processed into the shape that matches with cover glass tube tail end medial surface and establishing.
Fig. 6 provides the structural representation of an all-glass vacuum thermal-collecting tube.
In Fig. 6, arrange sealing-in by cover glass tube 2 and inner glass tube 3 nested, concentric, make an all-glass vacuum heat collector tube element.Inner glass tube 3 to stretch out forward and after inner vacuum pumping loading working medium, a heat pipe 1 is made in sealed-off from sealing-in place, and the length in heat pipe 1 hot junction is 1.8 meters.The outer surface of inner glass tube 3 makes absorbing film.Four paws jump ring 17 is arranged between cover glass tube 2 tail end and inner glass tube 3 tail end.