RU2809423C1 - Piston internal combustion engine with linear generator - Google Patents

Abstract

FIELD: engine building.

SUBSTANCE: invention is intended for efficient conversion of energy from various types of hydrocarbon fuels into electrical energy. A piston internal combustion engine with linear generator 18 is proposed, containing cylinder 1 made of non-magnetic material, on the end sides of which there are internal combustion engine semi-cylinders, each of which on the end side contains a combustion chamber, valve 6, 11 for adjusting the volume and compression ratio, ventilation valve 7, 12, injector 8, 13 and spark plug 9, and the parts of the semi-cylinders closest to the linear generator contain exhaust channels 5, 10. In the central part of the cylinder, on the outer side, stator 3 of linear generator 18 is installed with the possibility of connecting it to external load 15. The piston unit is represented by one shuttle 2, made with the possibility of free movement along the entire length of the cylinder from the combustion chamber of one half-cylinder to the combustion chamber of the opposite half-cylinder and consists of connected right and left pistons with sealing rings, between which an inductor represented by permanent magnets is installed.

EFFECT: ensuring high power density, reducing weight and dimensions, simplifying the design of an internal combustion engine (ICE) with a linear generator.

1 cl, 11 dwg

Description

Field of technology

The invention relates to the field of application of internal combustion engines and electrical engineering and is intended for the efficient conversion of energy from various types of hydrocarbon fuels into electrical energy.

State of the art

Linear generators are known from the prior art, for example, the generator according to RF patent No. 2517712 for generating electrical energy. Linear generators provide reciprocating motion of a cylinder with a magnet in the cylinder, while the energy is generated by an electric induction coil, and the movement of the piston (cylinder) is ensured by the pressure of the flowing medium in the end parts of the housing (cylinder)

Various linear internal combustion engines are also known; they are significantly simpler than classical internal combustion engines, since their design completely eliminates such a massive and complex system of parts as a “crank mechanism”

Linear internal combustion engines are divided into: opposed piston engines with external compression; with opposing piston and internal compression; single-piston, single-acting with a return mechanism; free-piston and double-acting free-piston.

The disadvantages of the engines listed above are the mechanisms and systems for generating electricity or transmitting torque, in which the actual efficiency of the engine itself is lost.

To efficiently generate electricity, linear generators are used in conjunction with linear internal combustion engines, for example:

known LINEAR MOTOR-GENERATOR according to RF patent No. 2462605, consisting of a working cylinder standing vertically on a base plate, finned on the outside, plugged from the lower end, containing a fuel injection nozzle in the lower part of the cylinder, holes for air intake and exhaust gases, opened and locked by the body piston; a piston moving up and down along the channel of the cylinder with compression rings and a rod on which permanent magnets are fixedly fixed; The generator windings are fixedly fixed above the cylinder and permanent magnets attached to the rod move up and down inside them. The disadvantage of this device is the relatively low engine efficiency, uneven piston speed and, as a consequence, energy production.

In addition to the solution mentioned above, various solutions are known from the prior art using internal combustion engines with a free piston to drive a linear electric generator, while various solutions are used to return the piston to the reverse position: springs, liquid working fluids, gas. Generators of this type have very high potential and can operate at very high frequencies providing high efficiency for a long time.

The closest prior art solution described in US Pat. No. 9,567,898, a high efficiency linear internal combustion engine comprises a cylinder having a cylinder wall and a pair of ends, the cylinder including a combustion section located in a central portion of the cylinder; a pair of opposing piston units configured to move linearly within the cylinder, each piston unit located on one side of the combustion section opposite the other piston unit, each piston unit includes a spring rod, and the piston includes a solid front portion adjacent to the combustion section and a gas section; and a pair of linear electromagnetic machines adapted to directly convert the kinetic energy of the piston assembly into electrical energy. The two-cylinder engine of the proposed design has a piston group consisting of two pistons connected by a rigid rod. The cyclically repeating gas pressure during the combustion process imparts reciprocating motion to the piston group. In the plane of symmetry of the rod, a movable magnetic system is fixed to the rod between the pistons. The moving magnetic system is located inside the stator structure with a winding system. When the rod with a magnetic system attached to it moves back and forth inside the stator and their magnetic fields interact, an electromotive force arises in the stator windings.

The disadvantage of this solution is the insufficient power and number of piston parts.

Disclosure of the Invention

The technical problem to be solved by the claimed invention is to ensure high power density of electricity generation.

The technical result of the claimed invention is that high power density is ensured due to the design of a linear generator and an internal combustion engine with a single piston unit.

To achieve the specified technical result, a piston internal combustion engine with a linear generator containing a cylinder made of non-magnetic material, on the end sides of which there are half-cylinders of the internal combustion engine, each of which on the end side contains a combustion chamber, a valve for adjusting the volume and compression ratio, a ventilation valve, an injector and a spark plug, in the central part of the cylinder on the outer side there is a stator of a linear generator with the possibility of connecting it to an external load, while the piston unit is represented by one shuttle, made with the possibility of free movement along the entire length of the cylinder from one combustion chamber of the semi-cylinder to the other combustion chamber of the opposite half-cylinder and consisting of connected right and left pistons with sealing rings, between which an inductor represented by permanent magnets is installed, the parts of the half-cylinders outermost to the linear generator contain exhaust channels.

The combination of the above essential features leads to the fact that:

The weight of the electrical installation is significantly reduced and the power density increases compared to existing power plants;

The volume of cylinders per unit mass increases significantly, which makes it possible to create a small-sized powerful power plant;

An increase in engine power can be achieved by simply lengthening the cylinder, without changing the design of the units and control system;

The efficiency of the engine and the entire installation as a whole increases due to the mode of complete expansion of gases in the cylinder;

It becomes possible to dynamically change the volume of the combustion chamber and the compression ratio in each stroke over a wide range by electronic control;

Reducing the number of moving parts to one piston unit;

Simplification of the design, absence of reciprocating motion guides.

Due to the high speed of movement of the inductor relative to the stator of the linear generator, increase the EMF, reduce the cross-section of the wires of the stator coils and reduce the weight of the generator;

It is possible to implement optimal fuel combustion modes, including homogeneous ignition of lean mixtures (HCCI combustion mode). Potential for reducing harmful emissions.

Brief description of drawings

In fig. 1 shows a diagram of a piston engine, on which the positions indicate:

1 - Piston engine cylinder;

2 - Engine piston unit;

3 - Linear generator stator;

4 - Stator windings of the linear generator;

5 - Left exhaust duct with pipe;

6 - Left valve for adjusting combustion chamber volume and compression ratio;

7 - Left petal ventilation valve;

8 - Fuel injection nozzle into the left half-cylinder;

9 - Spark plug of the left half-cylinder;

10 - Right exhaust duct with pipe;

11 - Right valve for adjusting the compression ratio;

12 - Right petal ventilation valve;

13 - Fuel injection nozzle into the right half-cylinder;

14 - Spark plug of the right half-cylinder;

15 - Generator load;

16 - Left half-cylinder;

17 - Right half-cylinder;

18 - Linear generator.

In FIG. Figure 2 shows a diagram of the piston unit, including:

19 - Left piston with sealing rings;

20 - Right piston with sealing rings;

21 - Connecting rod;

22 - Linear generator inductor in the form of a set of permanent magnets.

In FIG. 3-8 shows the working cycle of the left half-cylinder, where the following are indicated:

5 - Left exhaust duct with pipe;

6 - Left valve for adjusting combustion chamber volume and compression ratio;

7 - Left petal ventilation valve;

8 - Fuel injection nozzle into the left half-cylinder;

9 - Spark plug of the left half-cylinder.

In fig. 9 shows diagrams of pressure versus volume (P-V diagram) for the full expansion mode, and FIG. 10 and fig. 11 P-V diagram and for maximum power mode for a half-cylinder length of 1 meter and a diameter of 100 mm.

Carrying out the invention

Description of the device and the operation of its individual components.

Below is an example of a specific design of the device, which does not limit its design options.

The proposed piston engine differs from its analogues in that the energy generated in the cylinder of an internal combustion engine is converted into the kinetic energy of the piston, which freely accelerates along the cylinder to maximum speed, between two cylinders in which the chemical energy of fuels is converted into pressure according to the principle of engines internal combustion, located - the accelerating barrel along which the piston unit (piston) moves.

The kinetic energy of the piston unit, obtained as a result of converting the pressure in the cylinders into speed, is selected in the power take-off unit and converted into electricity, and the kinetic energy of the piston unit remaining after the power take-off is also used to compress the fuel-air mixture.

Cylinder volume, combustion chamber and compression ratios can be varied from cycle to cycle using special control valves located in each of the two cylinders.

The device makes it possible to implement a mode of complete expansion of the gas in the cylinder to atmospheric pressure to accelerate the piston unit, which will increase the engine efficiency.

A diagram of a piston internal combustion engine integrated with a linear generator is shown in Fig. 1

The piston engine consists of a cylinder 1, closed on both sides. Cylinder 1 is made of non-magnetic material and has smooth polished inner walls, like an ordinary cylinder of an internal combustion engine. Cylinder 1 is divided into right 17 and left 16 half-cylinders, between which a linear generator 18 is located. A piston unit 2 moves along cylinder 1, performing a reciprocating movement.

All processes, as in any other internal combustion engine, are controlled by a control system (not shown in the drawings). It controls the position of the shuttle and its speed using special sensors (not shown in the drawings) and sets a cyclogram of engine operation by opening and closing valves at the right moments, injecting the required amount of fuel and supplying voltage from sources (not shown in the drawings) to the spark plugs.

In FIG. Figure 2 shows piston assembly 2, which consists of right and left pistons with a rod connecting them and with sealing rings, a minimum number of which is 2 on each side, between which on the rod there is a set of permanent magnets, the number of which depends on the power and dimensions, the minimum quantity is 3 pcs. The magnets act as an inductor for a linear generator.

Half-cylinders can be built to operate on any of the existing cycles of an internal combustion engine - the Otto cycle with spark ignition, the Diesel cycle, as well as using compression ignition of homogeneous lean mixtures (HCCI combustion mode).

In FIG. 1 shows a spark ignition engine with direct fuel injection.

Each half-cylinder 16 or 17 contains:

In the end parts of cylinder 1 (half-cylinders 16 and 17):

- spark plugs 9 installed at the ends of cylinder 1 - combustion chamber (not shown in the figures);

- a valve for adjusting the combustion chamber volume and compression ratio 6 or 11, which is an ordinary seat valve, opened and closed by a solenoid according to commands from the engine control system;

- an injector used in the fuel systems of internal combustion engines 8 or 13 to inject fuel into the left or right half-cylinder, respectively;

- petal ventilation valve 7 and 12.

In the reverse parts of the semi-cylinders 16, 17 relative to the fuel combustion chambers, right 10 and left 5 exhaust ducts with pipes are installed.

The linear generator 18 consists of a linear generator stator 3, which is located around the central part of the cylinder 1, on its outer side. The design of linear generators is identical to known solutions and is described in the prototype. Stator coils 3 are connected to external load 15.

The claimed invention according to FIG. 1-3 is also a device that operates on the principle of an internal combustion engine, converting the pressure created by the working fluid when heated into the kinetic energy of an accelerating free projectile, which is the piston unit 2.

This energy is selected in the space between two half-cylinders 16 and 17 or using a linear generator 18.

In essence, the claimed device is two “guns” - combustion chambers directed against each other, “firing” alternately with a shuttle 2. On the way from one “gun” to another, power is taken off using a linear generator 18 and a “projectile” - piston unit 2 slows down, arriving at the opposite “gun” at the speed necessary to organize compression. The semi-cylinders 16 and 17 act as opposed “guns”, in which processes characteristic of the cylinders of internal combustion engines with a spark ignition or Diesel operating cycle are implemented, as well as a combustion mode with compression ignition of a lean homogeneous mixture (HCCI).

The dimensions of the semi-cylinders, diameter and length, as well as the size of the entire generator, are practically unlimited.

The minimum diameter of cylinder 1 can only be limited by the installation capabilities of spark plugs and valves.

The maximum possible diameter of cylinder 1 is limited only by the conditions of use, for example, for a power plant comparable in power to the installation of the icebreaker "Arktika" (two reactors of 160 MW each) a cylinder with a diameter of 1.8 meters and a half-cylinder length of 20 meters will be required.

The maximum length has no design restrictions.

In a classic internal combustion engine, the length of the cylinder is limited by the dimensions of the crank mechanism. In the above prototypes, an obstacle to increasing the length of the cylinder is the strength characteristics of the rods connecting the pistons.

In a shuttle motor there are no design restrictions for increasing length.

Without changing the diameter of cylinder 1 and without changing the dimensions and design of piston unit 2, it is possible to increase the length of the half-cylinder without restrictions, while the volume of the combustion chamber and the working volume of the half-cylinder, as well as the speed of the shuttle and the power of the generator as a whole, increase proportionally.

Examples of implementation

Description of the operation of a spark ignition engine The operating cycle of a shuttle engine consists of four cycles:

1. Duty cycle of the left half-cylinder 16;

2. Braking during forward motion with energy generation;

3. Duty cycle of the right half-cylinder 17;

4. Braking during return motion with energy generation.

Duty cycle of the left half-cylinder

In FIG. 3. The beginning of the cycle is shown. At the starting point, the shuttle moves to the left at a certain specified speed, which remains after the power take-off stage. The beginning of the cycle can be considered the moment when the left piston of the shuttle 2 intersects the exhaust pipe 5. The petal ventilation valve 7 is closed, and the valve for adjusting the volume of the combustion chamber and the compression ratio - 6 (KRKS) is forced open and fixed.

The piston unit 2 moves to the compression point and air exits from the semi-cylinder 16 into the atmosphere through the KRKS 6.

In FIG. 4. shows the moment the compression begins. The starting point of compression is determined by the control system based on several parameters:

- the required volume of the combustion chamber;

- the required pressure in the combustion chamber after compression, associated with the “compression ratio” parameter used in classic internal combustion engines;

- real speed of the piston unit after power take-off.

When the initial compression point is reached, the control system closes valve 6, fuel is injected in the required dose, and the process of compressing the fuel-air mixture in the combustion chamber begins.

In FIG. 5 shows the moment of completion of compression. It is characterized by the fact that all the kinetic energy of the moving piston unit 2 is converted into potential compression energy, and it stops. At this moment, a spark fires, the fuel-air mixture ignites, and the pressure in the combustion chamber increases.

In FIG. 6. shows the process of working acceleration of piston unit 2 (by analogy with the working stroke in an internal combustion engine). Under the influence of pressure, piston assembly 2 begins to move to the right, accelerating through cylinder 1. At the same time, the gas undergoes adiabatic expansion.

The initial acceleration acceleration depends on the initial pressure in the combustion chamber, the area of the piston and the mass of the piston assembly. During adiabatic expansion, the pressure in the half-cylinder drops as the shuttle moves to the right. As long as the excess pressure is greater than zero, the shuttle continues to increase speed.

The end of acceleration occurs when the piston assembly of the exhaust pipe is reached; the force moving the piston assembly will stop and it will begin to move by inertia.

In FIG. 7 shows the process of ventilation or purging of a half-cylinder.

The exhaust pipe 5 opens and, under the influence of pressure expansion, the exhaust gases remaining after expansion rush into the atmosphere at high speed.

After some time, a vacuum will arise in the semi-cylinder, which will lead to the opening of the petal ventilation valve 7. Outside air will begin to enter the semi-cylinder, replacing the exhaust gases.

To enhance the effect, valve 6 for adjusting the combustion chamber can also be forced open. During the return of the piston unit 2 to the starting point of the cycle, the semi-cylinder can be completely ventilated.

Unlike the solution adopted for the prototype, in the claimed solution:

1. The piston assembly moves freely in the cylinder from one half-cylinder to another, not limited by any guides other than the cylinder itself.

2. The result of the working cycle in a semi-cylinder is the acceleration of the piston assembly to the maximum possible speed, that is, the maximum accumulation of kinetic energy, unlike most internal combustion engines, where the pressure in the combustion chamber and in the cylinder is converted into force.

Thermodynamic cycle of a spark-ignition shuttle engine

Diagrams of pressure versus volume (P-V diagram) for the full expansion mode and for the maximum power mode for a half-cylinder length of 1 meter and a diameter of 100 mm are shown in the Figures. 10 and 11. The total volume of the cylinder is 7.85 liters.

Thermodynamic cycles of the engine may differ in the volume of the combustion chamber, which is selected by the control system from cycle to cycle based on external parameters, primarily in accordance with the load. The volume of the cylinder and combustion chamber is determined by the position of the initial compression force. Figure 10 shows the cycle for the full expansion mode. The starting point of compression is selected so that the gas at the end of half-cylinder 1 expands to atmospheric pressure, and all the expansion energy is converted into acceleration work. This mode is characterized by increased efficiency and low fuel consumption per kW of power.

It should be noted that the full expansion mode is essentially a minimum power mode, since a further reduction in the combustion chamber will lead to the fact that at the end of the semi-cylinder the pressure will be below atmospheric pressure and the resulting vacuum will slow down the piston unit 2.

Further increase in the volume of the combustion chamber will lead to an increase in power. At the same time, the exhaust pressure will increase.

The largest volume of the combustion chamber is obtained at the initial compression point located at the beginning of the semi-cylinder. This can be considered maximum power mode. The mode diagram is shown in Figure 11.

Claims (1)

A piston internal combustion engine with a linear generator, characterized in that it contains a cylinder made of non-magnetic material, on the end sides of which there are half-cylinders of the internal combustion engine, each of which on the end side contains a combustion chamber, a valve for adjusting the volume and compression ratio, a ventilation valve, an injector and spark plug, in the central part of the cylinder on the outer side there is a stator of a linear generator with the possibility of connecting it to an external load, while the piston unit is represented by one piston, made with the possibility of free movement along the entire length of the cylinder from one combustion chamber of the half-cylinder to the other combustion chamber of the opposite half-cylinder and consisting of connected right and left pistons with sealing rings, between which an inductor represented by permanent magnets is installed, the parts of the semi-cylinders outermost to the linear generator contain exhaust channels.