CN1153864A

CN1153864A - Vaneless steam turbine

Info

Publication number: CN1153864A
Application number: CN96103835A
Authority: CN
Inventors: 沈泉贵
Original assignee: Individual
Current assignee: Individual
Priority date: 1996-04-18
Filing date: 1996-04-18
Publication date: 1997-07-09
Anticipated expiration: 2016-04-18
Also published as: AU2502497A; CN1056435C; WO1997040259A1

Abstract

Vaneless steam turbine includes stator, rotor, end caps, main shaft and its bearings, inlet chamber, outlet chamber and other parts. The stator consists of conic inner and outer casings with water chamber in between and the inner casing has evenly distributed radial inlet and outlet holes with cap. The conic rotor is sleeved movably inside the stator and has cylinder with radial steam holes. The vaneless steam turbine has high power and afterheat recovery.

Description

Vaneless steam turbine

The present invention relates to a kind of steam turbine.

Blade type steam turbine after piston steam engine has been widely used in industrial production, its kind is a lot, though existing back pressure type, steam-extracting type, condensing type, resuperheat formula etc., but its basic structure is identical substantially, all be provided with the device of the multiple pressure power level structure of moving vane and stator blade composition, by steam (working medium) expansion working, effective thermal efficiency is up to 22%～38%.

The blade type steam turbine mainly comprises air chamber, nozzle (being first order stator blade), moving vane, stator blade, rotor, stator, main shaft, bearing shell, exhaust hood, bolt and thermal-protective coating etc., and agent structure has blade, rotor and stator.Except that a few pressure level full wafer angle of high-pressure section is identical, the dynamic and static blade of most pressure levels all is to begin to 70～85 ° of blade ends (axially) from 15～30 ° of roots (axially), by thick structure to thin twisted expansion shape, all the geometrical construction of blade is very complicated.

The object of the present invention is to provide a kind of obvious raising power engine power and effective thermal efficiency, mainly shrink the Vaneless steam turbine of the volume work done of (working medium) steam by condensation.

The present invention includes stator, rotor, end cap, main shaft, bearing, air chamber, exhaust hood, clamping bolt, foot rest and strong muscle sheet, the axle key stationary fit of main shaft and rotor, the two ends of main shaft and bearing connect into movingly, and two end cap is solid on two end faces of stator by the clamping bolt spiral shell.Stator is formed by the double-deck fit of inner casing, shell of band tapering, be the condensation hydroecium between inner casing and the shell, the condensation hydroecium is established intake pipe and waste pipe, inner casing is tapered tube shape, the axioversion angle of internal surface is 3～30 °, the circumference of inner casing is axially arranged with admission opening (also claiming nozzle) and the exhaust hole that equally distributed 6～20 roads have same intervals, its distribution angle that radially separates is 4～30 °, the steam vent direction is identical and become 35～65 ° inclination eccentric angle with the radial center vertical line, and becomes 90 ° with longitudinal center line.Each exhaust hole and next stage admission opening join, and the admission opening and the air chamber in the 1st road join, and the exhaust hole and the exhaust hood of extreme trace join, and each is to establishing the steam vent lid on adjacent admission opening and the exhaust hole, and air chamber is established steam inlet, and exhaust hood is established steam-expelling port.

Rotor is the conical cylinder shape, and be placed in the stator inner casing, rotor and stator are with tapering movingly, the axioversion angle of rotor circumference outer surface is identical with the tilt angle of stator inner casing internal surface, and it is identical with stator steam vent road number to establish number on rotor axial, and radially spaced angle is 2～25 ° a little cylinder, radial direction in the cylinder is identical and consistent with stator steam vent direction, cylinder backward is 20～45 ° towards the rear-inclined angle, preceding cylinder face diameter is 5～15 ° to the angle that recedes, and axial two sides becomes 90 ° in the cylinder with shaft axis.

Usually, the axioversion angle of stator inner casing internal surface can be 8～12 °, the circumference of inner casing axially evenly distributes and admission opening and exhaust hole with same intervals can be 12～16 roads, its distribution angle that radially separates can be 10～15 °, and the steam vent direction becomes 45～50 ° of inclination eccentric angles with the radial center vertical line.Epitrochanterian little path cylinder can be 5～10 ° to spaced angle, and cylinder backward is 35～40 ° towards backrake, and preceding cylinder face (radially) oblique angle that retreats is 5～10 °.

The present invention cooperates existing axle center propulsion device, coupling, centrifugal automatic speed governor, controls auxiliary device and relevant systems such as steam valve and control vapour curved bar, promptly constitutes a cover on-bladed steam turbine equipment.

Basic functional principle of the present invention is that steam produces huge pressure difference with the external world under the effect of high pressure, exist the potential energy that flows to low pressure from high pressure, produced huge motion energy, arrive in the little cylinder of rotor through nozzle and high speed impact, make the thermal power transfer of steam become kinetic energy to pass to rotor, this is to produce the impact force work done for the first time.When steam breaks away from little cylinder at a high speed, produce the recoil active force, the active force work done that promptly recoils for the second time, so steam each advance, one go out twice kinetic energy transmission work done that cylinder has all been done half-turn, this is to transmit kinetic energy, is the best approach that makes the thermal energy conversion.The little cylinder of each of per pass pressure level is all accepted the steam kinetic energy of friction speed, but because the power synthesis makes rotor produce great power.

In addition, be to reduce steam leaving loss, pressure at different levels falls and is not to solve by traditional expansion volume, because of steam and its volume of same quality is inversely proportional to, is unfavorable for the effective work done of hot machine, but condensing steam makes its volume shrinkage reach pressure to fall step by step.It has two big advantages: the firstth, do not reduce the closeness (be mass ratio) of vapor action on the effective stressed unit area of rotor, and because the quality-speed-inertial force in the motion is directly proportional, this is the optimum condition that obtains energy.The secondth, the waste heat that is obtained by water condensation contains higher temperature (high-grade thermal energy) can send the boiler recycling back to, effectively reduces the waste heat loss and finishes thermal cycle by main frame, carries out direct recovery waste heat, can improve waste gas residual heat significantly and reclaim.

Simultaneously, rotor and stator can reach the sealing limit, and this adopts adjustable sealing to realize.Because of the diameter of rotor little, be subjected to the radial pressure of steam again, and stator diameter is big, be subjected to the contrast of the centrifugal pressure of steam again, and the plasticity of metal, so the expansion coefficient of rotor less than stator, causes clearance for expansion big, therefore must adopt adjustable sealing, this is the necessary means that improves steamer power.

Obviously, compare with the blade type steam turbine of power with existing, the present invention has following advantage:

1. rotor and stator adopt same tapering, carry out again can reaching high concentricity from the phase break-in after fine finishing.Axially movable regulation and control are resolved gap that thermal expansion metal causes etc., and the adjustable gaps of rotor and stator makes its form the steam film sealing at the fluid of rotor surface to critical gap because of the gap is minimum, and the sealing of height can make this machine raise the efficiency 3%～5%.

2. equate that to pressure all around it and rotor travel forward synchronously and turn to exhaust port, steam to be discharged into down the nozzle of one pressure level because of steam in the little cylinder of rotor.Impact the loss of generation large drag forces so overcome blade type steam turbine (axially) high-velocity fluid mutually with (radially) high rotating speed blade, can raise the efficiency 6%～8%.

3. steam flow is done 180 ° angle of turn (work done) in little cylinder, improves the impact forces and the recoil active force of fluid dynamic energy effectively, can raise the efficiency 7%～9%.

Steam stator advance between the exhaust hole and lead in the vapour joint passage to flow, the flow resistance loss that produces because of (dilatation) step-down is very little, makes its kinetic energy be converted to that thermal energy is condensed that water absorbs and to take back boiler recycling, so overall thermal efficiency is lost not quite.Simultaneously, overcome existing blade type steam turbine and enlarged low-grade thermal energy that volume causes, promptly waste heat can't reclaim.This machine has special performance in this respect, can make whole heat recovery rate up to 30%～40% (recycling).

In sum, the raising of useful horsepower and heat recovery make the present invention improve the effective thermal efficiency height 20%～38% than existing blade type steam turbine.Obviously, because the pressure rating and the high or low power of varying number are different, so all types of no turbines improves the high and low different of useful horsepower, concrete data have only by all types of machines of design and need and decide.

Fig. 1 is radial section figure of the present invention.

Fig. 2 is an axial half-sectional view of the present invention.

Fig. 3 is a radially fundamental diagram of the present invention.

Fig. 4 is an axial fundamental diagram of the present invention.

As shown in Figure 1, 2, the present invention includes stator (1), rotor (10), end cap (13,18), main shaft (12), bearing (16), air chamber (2), exhaust hood (8), clamping bolt (15,17), foot rest (24), strong muscle sheet (26) etc.

Stator (1) is formed by inner casing (5) and shell (6) fit, inner casing (5) is tapered tube shape, forms the stator (1) of bilayer zone tapering, and the interlayer of inner casing and shell is condensation hydroecium (23), condensed water flows into the condensation hydroecium from intake pipe (21), flows out from waste pipe (22).It is that 10 ° 12 roads are radially with the admission opening (3) and the exhaust hole (4) of 45 ° of eccentric angles that inner casing is provided with spaced symmetrically angle, 12 road steam vents all constitute one-in-and-one-out 36 groups of steam vents separately on same axis, each steam vent (axially) becomes 90 ° with center line, and the radial direction unanimity, the one-way eccentric angle of inclination is 45 °.The exhaust hole of upper level is connected with the admission opening of next stage, the admission opening in the 1st road is connected with air chamber (2), the exhaust hole in the 12nd road is connected with exhaust hood (8), and the steam inlet of air chamber (2) is established admission flange (19), and the steam-expelling port of exhaust hood (8) is established steam discharge flange (20).On each group admission opening of the circumferential outer surface of inner casing and exhaust hole, establish steam vent and cover (7).

Rotor (10) is the conical cylinder shape, and is placed in the inner casing of stator, and the same tapering of formation rotor and stator movingly.The axioversion angle of rotor circumference outer surface is consistent with the angle of inclination of stator inner casing internal surface, and its tilt angle can be designed to 3～30 °.And on rotor, establish the little cylinders in 12 roads (9), its distribution angle that radially separates is 8 °, radial direction in the little cylinder is identical and consistent with stator steam vent direction, cylinder backward is 35 ° towards the rear-inclined angle, preceding cylinder face diameter is 5 ° to the angle that recedes, and (axially) two sides becomes 90 ° in the little cylinder with shaft axis.

Main shaft (12) adopts axle key (11) stationary fit with rotor (10), and the center of two end cap (13,18) can be adopted and be slided or rolling bearing (16), and is solid with bolt (15) spiral shell bearing cap (14) during assembling, and solid on two end faces of stator with bolt (17) spiral shell.Establish lower margin screw (25) on the foot rest (24).

During practicality, can suitably increase steam seal ring, thermal-protective coating etc., and be equipped with auxiliary device and relevant systems such as existing axial advance device, coupling, centrifugal automatic speed governor, control steam valve and control vapour curved bar, promptly constitute the vaneless steam turbine equipment of a cover.

In Fig. 1, working medium (steam) enters the air chamber (2) on stator (1) top along the double-lined arrow direction, and the nozzle (3) that makes whole first pressure level is that the whole pressure of admission opening are even.High pressure steam obtains acceleration in the steam vent road of first order nozzle (3), produce huge motion energy, i.e. the impact energy of fluid, and steam impact at a high speed produces kinetic energy transfer function (being work done) in little cylinder (9) lining of rotor (10).

The steam that enters little cylinder (9) lining first pressure level along with rotor (10) to previous crops (radially) motion (seeing Fig. 2 radial section part), flow out during to the exhaust hole (4) of first pressure level.Steam advances at first pressure level one, one go out to have finished the i.e. work done for the first time of kinetic energy transfer function for the first time.

The steam of being discharged by first pressure level moves to (axially) low pressure stage along steam vent lid (7) internal channel, the nozzle (3) that enters second pressure level impacts once more, little cylinder (9) lining at the second road pressure level of rotor (10), steam one advances for the second time, one go out, and the second road pressure level has produced the i.e. work done for the second time of kinetic energy transfer function for the second time.

Return resurgent from high pressure to the low pressure direction step by step moves, returns multiple impact to steam in proper order thus, transmit the kinetic energy effect, pressure descends step by step, steam at last not the level (the tenth secondary) nozzle (3) carry out last work done, after the exhaust hole (4) of level (the tenth secondary) is not discharged to exhaust hood (8), converge, all discharge.

Fig. 3 makes working medium (steam) that the schematic representation that (radially) eccentricity pressure produces rotation torque power take place.The generation of eccentric torque power is present in (radially) inclination eccentric opening to be made vapor stream cause eccentric inertia impulsive force and eccentricity pressure and constitutes.

Because stator inner casing (5) and circumference are when processing (mill or bore) nozzle (3) and exhaust hole (4), just adopt same (radially) inclination eccentric opening processing method, it is 35～65 ° that (radially) the inclination eccentric angle in hole and the central vertical line of stator (1) form gradient, and the size of eccentric angle directly is directly proportional with the size of torque force.

In Fig. 3, Fig. 4, steam one advances, one go out, the little cylinder (9) of rotor (10) all is to finish 180 ° turning motion in cylinder, select the mode of the transmission fluid dynamic energy (work done) that comes and goes (admission produces percussion, and steam discharge produces the recoil effect) at 180 ° of angles of working medium generation to improve the best angle selection that working medium transmits kinetic energy effectively.

Steam produces (axially) motion that decompression is quickened in the passage of the steam vent lid (7) of stator (1), the dilatation of steam vent lid (7) produces and preserves energy, makes down one pressure level have sufficient quality of steam to increase and transmits energy (quality in the motion is directly proportional with energy).The quality that increases working medium step by step can be the another special selection of this structure.

The present invention is to the drag reduction of vapor stream, acceleration mainly is to adopt condensing steam, make its volume shrinkage step-down, it is opposite fully with the working principle that the expansion drag reduction that enlarges volume quickens with the blade type steam turbine, selection makes working medium produce shrink non-bloating working principle, just recovered steam waste heat recycling utilization effectively.Stator (1) adopts inner casing (5) and shell (6) tube-in-tube structure seal arrangement to do freezing mixture with condensed water (23) and plays two effects.Its volume shrinkage generation pressure falls in one, cooling down high-temperature steam, reaches and reduces flow resistance and accelerating fluid effect.Its two, high-temperature steam produces heat exchange action through the large-area transmission of heat of metal and the thermal radiation of inner casing (5) and steam vent lid (7), steam waste heat is recovered utilizes raising to reach 30%～40% (cyclic utilization rate).

The huge torque force that produced of device is from all the tilt summation of steam eccentricity pressure of eccentric opening of whole device, and the power (being rotating mechanical energy) that device is produced is percussion and the counteractive kinetic energy energy delivered summation that produces high flow rate from the steam high pressure.

In sum, this device belongs to new external combustion thermodynamic machine.

Obviously, the internal surface of the inner casing (5) of employing stator (1) is consistent with the outer surface of rotor (10), be processed into the circular cone barrel structure of same inclined slope tapering, after the effect of same tapering is that single match grinding closes, tapering can regulate optimal seal gap is arranged, eliminate the nonconcentricity error that machining and build-up tolerance cause.The tapering of (axially) inclined slope helps regulating seal clearance and improves sealability.Many because of adopting (6～20) pressure level structure so fully improve the steam discharge leaving velocity energy utilization ratio of steam, improves mechanical output.It is the needs that increase eccentricity pressure and increase capacity that stator adopts porous structure.Under the situation that is not influencing welding steam vent lid, advance, 4～30 ° of the circle distribution angle Selection of exhaust hole.All per pass steam vent (axially) center line on the appearance circumferential surface of stator inner casing of pressure level all gets consistent.Nozzle exhaust hole and central vertical line formation gradient are 35～65 ° eccentric angle.

Rotor (10) adopts the scheme of a plurality of little cylinders (9) to increase effective lifting surface area, improved power, (axially) pressure progression of little cylinder (9) should be identical with stator (1) pressure progression, the little cylinder of each pressure level (single, double number) is not limit, (axially) center line of cylinder needn't align between every grade, can increase the torque force orientation.(radially) distribution angle of the little cylinder of per pass pressure level (9) is 2～25 °, circumference uniform distribution, (axially) both sides cylinder face in each little cylinder (9) becomes 90 ° with axial line, the cylinder face and the rear-inclined angle of (radially) in each little cylinder (9) are 20～45 °, produce whirlpool vapour loss in the time of can reducing steam into and out of cylinder, (radially) preceding cylinder in each little cylinder (9) is 5～15 ° towards the rear-inclined angle, the favourable steam impringement power of accepting, the centrifugal action that produces when reducing rotor (10) running.

Employing condensed water and steam convection action have improved rate of heat exchange and cooling effect, and improve water-exit temperature, reduce stripping temperature, increase the UTILIZATION OF VESIDUAL HEAT IN value.

Adopt steam vent lid (7) sectional area capacity greater than advance, 2～10 times of the sectional area of exhaust hole (4) and capacity, helping steam does quicken to flow and increase quality in (axially) and can collect the storage effect, can enlarge heat diffusion area with steam vent lid (7) structure, increase cooling effect.

Stator (1) and rotor (10) all adopt overall structure, and its effect is to improve the tension of metal under the thermal stress effect, shearing strength, the mechanical property of raising metal.Stator (1) and rotor (10) adopt and do not rub movingly, make apparatus main body not produce mechanical wear, favourable raising working life.

Between each pressure level and the first order and the most not the level all be provided with steam seal ring (26), improved the gas seal action.

Claims

1, Vaneless steam turbine, comprise stator, rotor, end cap, main shaft, bearing, air chamber, exhaust hood, bolt, foot rest and strong muscle sheet, the axle key stationary fit of main shaft and rotor, main shaft two ends and bearing are connected into movingly, two end cap is solid by the bolt spiral shell, it is characterized in that:

1) stator is formed by the double-deck fit of inner casing, shell of band tapering, be the condensation hydroecium between the inside and outside shell, the condensation hydroecium is established intake-discharge pipe, inner casing is tapered tube shape, the axioversion angle of internal surface is 3～30 °, and the circumference of inner casing is axially arranged with admission opening and the exhaust hole that there is same intervals in equally distributed 6～20 roads, and its angle of distribution that radially separates is 4～30 °, the steam vent direction is identical and become 35～65 ° of inclination eccentric angles with the radial center vertical line, becomes 90 ° with longitudinal center line; Each exhaust hole and next stage admission opening join, and the admission opening and the air chamber in the 1st road join, and the exhaust hole and the exhaust hood of extreme trace join, and each is to establishing the steam vent lid on adjacent admission opening and the exhaust hole, and air chamber is established steam inlet, and exhaust hood is established steam-expelling port;

2) rotor is the conical cylinder shape and is placed in the stator inner casing, rotor and stator are with tapering movingly, the axioversion angle of rotor circumference outer surface is identical with the tilt angle of stator inner casing internal surface, it is identical with stator steam vent road number to establish number on rotor axial, and radially spaced angle is 2～25 ° a cylinder, radial direction in the cylinder is identical and consistent with stator steam vent direction, cylinder backward is 20～45 ° towards backrake, preceding cylinder face diameter is 5～15 ° to the oblique angle that retreats, and axial two sides becomes 90 ° in the cylinder with shaft axis.

2, Vaneless steam turbine as claimed in claim 1, the axioversion angle that it is characterized in that stator inner casing internal surface is 8～12 °, admission opening and exhaust hole are 12～16 roads.

3, Vaneless steam turbine as claimed in claim 1 is characterized in that the distribution angle that the circumference of stator inner casing radially separates is 10～15 °, and the steam vent direction becomes 45～50 ° of inclination eccentric angles with the radial center vertical line.

4, Vaneless steam turbine as claimed in claim 1 is characterized in that epitrochanterian path cylinder is 5～10 ° to spaced angle, and cylinder backward is 35～40 ° towards backrake, and preceding cylinder face (radially) oblique angle that retreats is 5～10 °.