JPS61171831A - Free-piston type gas turbine - Google Patents

Abstract

PURPOSE:To obtain the small-sized and lightweight apparatus by installing a cylinder block having a free piston inside a turbine and forming a combustion chamber between the cylinder block and the free piston. CONSTITUTION:A cylinder block 8 having a free piston 9 is installed inside a turbine 6 having turbine blades 5. After the combustion gas supplied form the combustion chambers 10A and 10B between the cylinder block 8 and the free piston 9 is introduced into an expansion chamber 20, said gas is blown towards the turbine blades 5 from a blow-out port 21. Therefore, the apparatus can be made small-sized and lightweight.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical field to which the invention pertains) The present invention relates to a free piston type turbine.

(Conventional technology) Conventionally, as a free piston type gas turbine.

A diesel gas turbine as shown in FIG. 5 is known. In this case, air is introduced into the compressor cylinder 52 through intake holes 51 provided on both sides of the gas generator 50, and is introduced into the air chamber 55 through the exhaust valve 54 when the free piston 53 performs a compression stroke. This compressed air enters the combustion chamber 57 through the intake hole 56 provided on the left side.

The gas combusted in the combustion chamber 57 that performs scavenging and supercharging is sent from an exhaust hole 58 to a turbine 59 to drive the turbine 59. 60 is an air cushion, 61
is an injection valve.

(Prior art and problems) Conventional diesel gas turbines are flow-based machines like normal gas turbines, so they require a large gas flow and a large gas generator 50. Since the container 50 is of the opposed piston type, one of the pistons 53
Gas can be generated only once in a round trip, which inevitably increases the size of the device, and in order to operate the turbine 59 in the flow system, the thermal energy (blowdown energy) of the gas exiting from the exhaust hole 58 is reduced to a static pressure. Therefore, problems such as large energy loss were inevitable.

(Means for Solving the Problems) This invention provides a cylinder block 8 having a free piston 9 inside a turbine 6 of a gas turbine that obtains rotational force by blowing high pressure gas onto the turbine blades 5. Combustion chamber 10A whose capacity changes depending on the movement of
After alternately repeating intake-compression-ignition-combustion-explosion in 10B, and guiding the combustion gas to the expansion chamber 20 to make it static pressure,
The blower outlet 21 is sprayed toward the empty turbine blade 5.
Since the bin 6 is rotated, smooth rotation is possible, efficiency is high due to effective use of dynamic pressure energy, and the entire gas turbine cycle system can be made smaller and lighter.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

The output shaft side housing 2 is assembled on one side of the cylindrical gas turbine main body 1, and the exhaust side housing 3 is assembled on the other side. They are fixed together by a bolt 4.

A turbine 6 having a large number of turbine blades 5 mounted on its inner circumferential surface is rotatably provided within the front-packed gas turbine main body 1 . This turbine 6 is connected to an output shaft 7 that is pivotally supported by the side housing 2 on the output shaft side.

A cylinder block 8 fixed to the exhaust side housing 3 is provided inside the turbine 6, and a free piston 9 is fitted into the cylinder block 8. Two variable combustion chambers 10A.

10B is formed.

A starting point 1 is provided on one end surface of the cylinder block 8.
A spark plug 11 and an air valve 12 with a starting fuel injection valve are attached, and a starting air valve 13 is attached to the other end.

In addition, two combustion chambers 10A are provided on the side of the cylinder block 8.
, an intake port 14 and an exhaust port 15 are provided which are alternately opened by movement of the free piston 9 opened in the IOH. The intake port 14 is connected to the carburetor 1 through an intake check valve 16.
7 and an air cleaner 18. Further, the exhaust port 15 is connected to the expansion chamber 20 via an exhaust check valve 19.

The expansion chamber 20 is provided in a semicircular space formed between the turbine blade 5 and the cylinder block 8, and has a tapered air outlet 21 that opens toward the turbine blade 5.

A plurality of exhaust ports 22 are provided on the side surface of the turbine blade 5 of the exhaust side housing 3, and the ports 22 are connected to an exhaust pipe 23. Reference numeral 24 denotes a bleed pipe for exhausting the mixed gas between the gas turbine main body 1 and the turbine 6; one end thereof is opened on the inner circumferential surface of the gas turbine main body 1 near the bearing, and the other end is a bleed nozzle 25 provided in the exhaust pipe 23.
It is connected to the. 26 is a cooling air intake provided in the output shaft 7, 27 is a cooling fin, 28 is a cooling 30 is a starting spark plug power input terminal, and 31 is an engine mounting base.

Next, the operation of the free piston gas turbine of the present invention will be explained.

a. Operation of gas generator First, at the time of starting, when the starting air valve 12.13 is opened, compressed air flows into the combustion chamber 10A and IOH, and the free piston 9 is activated by the pressure of the compressed air from the air valve 12.13. Moving. At this time, the free piston 9 is moved to the top dead center on the combustion chamber 10A side. (The free piston 9, which has been injected from the injection valve attached to the air valve 12 and moved by the pressure on the combustion chamber 10A side, is ignited by the starting ignition Zorag 11 when it reaches near the top dead center and the compression pressure has increased. At this time, combustion chamber 10
In A, a mixed gas (a mixed gas of lubricating oil and kerosene for lubricating the piston and cylinder) from the carburetor 17 flows into the combustion chamber 10.
The air is sucked in through the intake port 14 on the A side. This suction ends near the top dead center on the combustion chamber 10B side. The ignition causes the fuel to explode and presses (moves) the free piston 9 toward the combustion chamber 10A. Free piston 9 is in combustion chamber 10A
When the mixed gas starts to move to the side, the air blowback toward the intake port 14 is blocked by the intake check valve 16, so that the mixed gas is forced toward the combustion chamber 10A. During the compression process of the mixed gas, residual gas is expelled until the piston 9 closes the exhaust port 15.
(Some new mixed gas also leaks) When the exhaust port 15 closes, strong compression occurs and the heat of compression ignites and burns (mixed gas)
explodes and burns. At this time, the mixed gas is being sucked into the other combustion chamber 10B.

Due to this explosive combustion, the free piston 9 moves toward the combustion chamber 10B, contrary to the above, and when the exhaust port 15 opens, the combustion gas flows out into the expansion chamber 20.

At this time, the other combustion chamber 10B is in the compression process, and the combustion chamber 10B is in the compression process.
When the exhaust port 15 on the B side closes, it is strongly compressed and ignited by the heat of compression, resulting in explosive combustion and the free piston 9 moves again to the combustion chamber 10A side.

Thereafter, intake, compression, combustion, and exhaust are repeated twice in one reciprocation of the free piston 9. This operation is basically similar to a two-stroke engine, except that it does not require a scavenging pump. That is, suction of fuel (mixed) gas is performed by lowering (moving) the piston. This is the same as the intake operation of a four-stroke engine.

b. Operation of the gas turbine Combustion gas generated by the operation of the gas generator described above is sent from the exhaust port 15 of the gas generator (cylinder block 8) to the expansion chamber 20 via the exhaust check valve 19. Expansion chamber 2
At 0, the gas flow that is intermittently exhausted from the exhaust port 15 is expanded once in order to make the combustion gas with large pressure fluctuations generated by the closed cycle as close as possible to the continuous (average pressure) gas flow required for the turbine. Averaged in chamber 20 and air outlet 2
Gas at approximately constant pressure (static pressure) continuously from 1! .

As a flow, the flow velocity is increased and it is blown onto the turbine blades 5.

At this time, the blades 5 and the air outlet 21 are positioned so that all the energy is transmitted to the turbine blades 5, thereby eliminating energy loss.

A plurality of exhaust ports 22 for discharging the C0 operation end gas are provided in the exhaust side housing 3, and each of these exhaust ports 22 is connected to a continuous exhaust pipe 23.
It is connected to the. Therefore, since the gas blown onto the turbine blades 5 is blocked from flowing to the side by the side housing 3, it flows along the circumferential direction of the turbine 6 to the nearest exhaust port 22. It is discharged into the atmosphere through the exhaust pipe 23. Furthermore, exhaust/-)
When gas flows into the exhaust pipe 23 from the exhaust pipe 22, a part of the exhaust port 22 is sloped along the gas flow to prevent the flow of gas from leaking out. .

d. Output extraction The turbine 6 is cantilever-supported by an output shaft 7 that is pivotally supported by the output shaft side side housing 2, and the rotation of the turbine 6 rotates the output shaft 7 and extracts rotational output from the output shaft 7. .

Note that when the rotation speed of the output shaft 7 does not match the rotation speed of the equipment used, an increase/reducer gear (not shown) may be connected to the output shaft 7.

e. Lubrication This turbine is lubricated by a gas mixture of fuel (kerosene) and lubricating oil, which is the same as in a normal two-stroke engine. That is, the gas generator (free piston 9) is provided with a piston ring between the piston 9 and the cylinder block 8, and is lubricated by the mixed gas. In addition, the bearing (goal bearing) of the output shaft 7 bleeds a part of the combustion gas with a bleed nozzle 25 provided near the outlet of the exhaust pipe 23 and guides a part of the combustion gas to the bearing part for lubrication. The combustion gas is discharged into the exhaust pipe 23 from the bleed nozzle.

f. The cooling gas generator is cooled through the cooling air intake port 2 provided on the output shaft 7.
6 to the cooling fins 27 provided on the turbine 6 to forcibly cool the outside air. The cooled air passes between the turbine 6 and the side housings 2 and 3, is guided to the exhaust port 22, and is discharged to the atmosphere again through the exhaust pipe 23. At this time, the residual gas is driven out by the flow of cooling air so that the residual gas does not flow into the turbine blades 5 and reduce the output efficiency of the turbine 6.

(Effects of the Invention) Since combustion gas can be easily generated from the cylinder piston and K, high pressure gas can be efficiently obtained through a closed cycle. Since it is the same as a general reciprocating engine, it is easy to handle and has good control response.

Since it uses constant torque gas energy obtained in a closed cycle instead of continuous combustion gas like a general turbine, it can obtain good torque characteristics without rotating as fast as a general turbine, so the output rotation can be continuous. Since the speed can be slowed down, it can be used directly without using auxiliary equipment such as a speed reducer.

Since the moment of inertia is reduced and the rotational speed is increased, there is no need for a flywheel like in a general reciprocating engine, and stable output rotation is obtained with small rotational fluctuations of the output shaft.

Furthermore, since the gas generator is installed inside the turbine, the combustion noise is low, and since it is a continuous gas generator, it is easy to reduce the size and weight, and the manufacturing cost can be kept low.

[Brief explanation of the drawing]

FIG. 1 is a side sectional view showing an example of the apparatus of the present invention, FIG. 2 is a longitudinal sectional view thereof, and FIGS. 3 and 4 are left and right side views thereof. FIG. 5 is a schematic diagram of a conventional diesel gas turbine. 5... Turbine blade, 6... Turbine, 8...
・Cylinder block, 9...Free piston, 10A
. 10B... Combustion chamber, 20-... Expansion chamber, 21... Air outlet.

Claims (1)

[Claims] 1) In a gas turbine that obtains rotational power by blowing high-pressure gas onto turbine blades (5), a cylinder block (
8) is provided, and the combustion chambers (10A, 10B) whose capacity changes with the movement of the free piston (9) alternately repeat intake-compression-ignition-combustion explosion, and the combustion gas is transferred to the expansion chamber (10A, 10B).
A free-piston type gas turbine is characterized in that the blower turbine (6) is rotated from the blower outlet (21) toward the turbine blade (5) after the air is introduced into the gas turbine (20) and the pressure is made static.