RU2132476C1 - Rotary stirling engine with external heat supply - Google Patents

Abstract

FIELD: engine manufacture. SUBSTANCE: engine has rectangular-section annular stator accommodating rotor mounted on fixed axis of revolution and provided with blades sliding over inner generating line of stator. Blades compress working medium (gas) in compression chamber at top dead center and convey it over stator channels to heater wherein it is heated to 600 K. Heated gas is conveyed over stator channels arranged at 45 deg past TDC to front working chamber held at compression chamber pressure. In this chamber, working medium expands first according to isobar and then, upon disconnection from heater, according to adiabatic curve; heat of expanding gas is converted into mechanical work of revolving rotor and working medium completes its flow in expanding cooler and returns to initial condition. Engine operates in closed double-stroke cycle. Important feature of engine is difference in areas of each channel blades. With five blades, compression chamber shut-off is ensured and pressure within chamber rises after every turn of rotor through 72, 45, and 27 deg. Energy is supplied from concentrated sun rays incident on heater which makes engine useful for space vehicles. Natural gas is used for engines operating on ground. EFFECT: improved efficiency of engine. 3 dwg

Description

 The invention relates to engine building.

 The Rotary Stirling (DLS) engine refers to gas engines operating by expanding the working fluid (gas) heated in an external heater, and operates in a closed cycle.

 The proposed DRS (see Figs. 1 and 2) is compact, can be installed on cars, motorcycles, tractors, and also can be used stationary (for example, paired with an electric generator, pump, saw) with a power of 5 to 500 hp.

 DLS compares favorably with piston Stirlings by its simple design, low weight, and sufficient power. Piston Stirling operates at a monstrous pressure of 150-200 bar (which leads to a complication of the design of the engine, its weight). DLS operates at a pressure of no higher than 10 atm, which removes dozens of problems. This affects the cost: DLS is 10-20 times cheaper in the production of Stirling piston.

SUMMARY OF THE INVENTION A rotary engine with an external supply of heat consists of a ring stator of rectangular cross section, inside of which a rotor rotates with a fixed axis, with blades sliding along the inner stator generatrix only along the end line, and they are inactive to the lateral planes of the rotor. The blades compress the working fluid (gas) in the compression chamber at TDC, and the compressed gas is directed through the channels in the stator to the heater, where it is heated to 600K and is heated through the channels in the stator, located 45 ^o after TDC, in front of the working chamber with pressure compression chambers. The working fluid expands first along the isobar, and after being disconnected from the heater, along the adiabat, the heat of the expanding gas turns into the mechanical work of the rotating rotor, and the working fluid at the BDC ends its path in the refrigerator-expander and returns to its original state.

In FIG. 1 shows the engine in a section along AA perpendicular to the axis of the rotor, where the position of the center O _{1 of} the rotor axis, the center O _{2 of} the stator axis and the cylindrical eccentric, the section of the rotor ring 8 with the position of the blades 6 and the windows 7, the compression chamber 15 in the equilibrium position TDC, the working chamber 17, the stator 10 in the context, on it channels: injection of compressed gas 14 into the heater, the passage of hot compressed gas through channel 16 from the heater to the working chamber 17, the purge channels 19 and 20 through the refrigerator expander 18, the compression chamber 21.

 In FIG. 2 is a section along BB motor, where axis 1 with an eccentric 5 is visible, bearings 2, axis mount in housing 4, rotor ring 8, high lateral planes of rotor 9, creating, together with the blades and stator 10, movable chambers of working stroke and cold compression gas channels, hot gas 16, purge channels 19 and a cross section of the refrigerator expander 18, which shows one of the five partitions with “tails” 22 for cooling and mixing the hot gas coming from the chamber, where the working stroke ended. The device of the rotor 3 as a whole, covering the lateral planes 9 of the stator 10 with seals 13 is clearly visible. The motor housing 4 is shown approximately, which covers the rotating parts from the external environment.

In FIG. Figure 3 contains the DDS operation diagram explaining the moment of heat supply Q ₁ and explaining the moment of the start of operation of the compression chamber and the work of adiabatic expansion of gas, where 1 is the end of compression, heating to 600 K, effective pressure = 10 atm; 2 - heater shutdown, pressure increase to the maximum; 3 - the beginning and continuation of adiabatic expansion; 4 - adiabat working stroke; 5 - the working stroke of the chamber with a maximum pressure> 10 bar (Q ₁ is the heat communicated to the working fluid in the heater, Q ₂ is the heat given off by the working fluid in the cooler). Below is the Vp diagram, built on several reliable points, by which one can judge the efficiency of the engine.

 Device (see Figs. 1 and 2).

 On the fixed axis 1 rotor 3 rotates on bearings 2. The axis is fixed in the motor housing 4. A cylindrical eccentric 5 is made on it, on which the blades 6 are supported, passing through the windows 7 of the annular part 8 of the rotor. The rotor has lateral planes 9, between which there are blades rotating together with the rotor and sliding along the inner surface of the stator 10, which is rigidly connected to the motor housing by the protrusion 11.

 On the lateral surfaces of the stator, grooves 12 are made around the circumference, in which fluoroplastic seals 13 are installed (see Fig. 2), which ensure the tightness of the movable connection of the rotor with the stator.

O ₁ is the axial center of the rotor, O ₂ is the axial center of the stator and cylindrical eccentric. The distance O ₁ O ₂ is equal to 0.1 of the inner radius of the stator.

On the stator (see Fig. 1), channels 14 are made at 10 ^° to TDC, supplying compressed gas from the compression chamber 15 to a heater (not shown in the drawings) and 45 ^° after TDC, channels 16, through which compressed and heated gas from the heater passes into the working chamber 17.

 At NMT, a refrigerator expander 18 is installed, connected to the stator by channels 19 and 20. Under the residual working pressure, a part of the exhaust gas is blown through channels 19 and 20 through a cooler-expander 18 and cooled to a chamber with a low pressure (about 1.5 atm). compression 21.

 Act.

To actuate the engine, you must first warm up the heater to 300 ^o C (≈600K) and start the DLS in the right direction; the blades (see Fig. 1), moving around the circumference of the eccentric, are pressed by centrifugal force to the stator and begin their work: chamber 21 compresses the cold working fluid, compression ends in chamber 15, compressed gas passes to the heater through channel 14, where heat is communicated to it Q ₁ , the pressure rises to 10 atm, since at the same time hot gas replenishes the expanding working chamber 17.

 The process goes the direct way: compression chamber - heater - working chamber. The gas path has been simplified, and there are no unnecessary movements in the engine mechanism.

Under a pressure of 10 atm, the gas enters the working chamber 17 and picks up the rotation of the rotor. At the same time, the compression chamber 15 (Fig. 1) goes out of balance at the TDC, because the leading blade becomes more driven and is also included in the work. After passing the driven blade of the mouth of channel 16, the working chamber is disconnected from the heater and then works by expanding the working fluid from 10 at to 4 at adiabat. The pressure of the working fluid decreases to 4 atm, the temperature decreases. But the torque does not change, because simultaneously with a decrease in pressure, the radius of the active part of the scapula increases. With further movement of the rotor, the working chamber comes to the BDC, the purge channels 19 and 20 open and the cooler-expander 18 is turned on (see Fig. 1), where excess heat Q ₂ is released into the atmosphere: the gas comes to its original state and the cycle ends (see Fig. 1 and 3).

 As in the Stirling engine, DLS works due to the heat transferred to the working fluid by an external source.

Compared to piston Stirling, a rotary rotor is much simpler. The gain is achieved due to the following:
- no piston, rhombic mechanism, crankshaft,
- no regenerator,
- direct movement of the working fluid (less loss),
- five chambers - five working strokes per revolution,
- the rotor itself serves as a flywheel,
- high torque
- the constancy of torque throughout the entire stroke (the arm of the moment increases towards the end of the stroke),
- it is possible to increase the internal gas pressure in the engine (put the entire engine together with the electric generator in an airtight chamber),
- high engine efficiency - not less than 65%,
- no spark plugs,
- there is no gas distribution mechanism.

Sources of information
1. Stirling Engines .- M.: Mechanical Engineering, 1977 (edited by MG Kruglov).

 2. Technical thermodynamics with the basics of heat transfer and hydraulics .- L .: Engineering, 1988 (N.G. Lashutina, O.V. Makashova, R.M. Medvedeva).

 3. Fundamentals of the theory and design of automotive engines. - M.: Higher school, 1973 (MD Artamonov, MM Morin).

Claims (1)

A rotary engine with an external supply of heat, consisting of a circular stator of rectangular cross section, inside of which a rotor rotates with a fixed axis, with blades sliding along the inner stator generatrix only along the end line, and they are inactive towards the lateral planes of the rotor, compress the working fluid (gas) in the chamber compression at TDC and compressed gas through the channels in the stator is directed to the heater, where it is heated to 600K, and heated is directed through the channels in the stator, located 45 ^o after TDC, to the working chamber ahead with pressure the compression chamber, the working fluid expands first along the isobar, and after being disconnected from the heater, along the adiabat, the heat of the expanding gas turns into the mechanical work of the rotating rotor, and the working fluid at the NDC ends its path in the refrigerator-expander and returns to its original state.

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