RU2844365C1 - Rotary external combustion engine with dynamic heat exchangers - Google Patents

Abstract

FIELD: mechanical engineering.

SUBSTANCE: invention relates to propulsion engineering, particularly, to external combustion engines. Rotary internal combustion engine consists of housing (1) with cavities formed by three rotors (2, 3, 4). Design of cavities is described, at the same time the specified cavities of three rotors are the cavity of the heater, the cavity of the regenerator and the cavity of the cooler, in which expansion chamber (5), cooling chamber (6), heating chamber (7) and compression chamber (8) are formed. Heater rotor (2) has inlet process opening (10), refrigerator rotor (4) has outlet process opening (9). Process openings connect the regenerator cavity heating chamber (7) to the refrigerator cavity compression chamber (8) and to the heater cavity expansion chamber (5). Invention discloses rotors design with possibility of their synchronisation. Heater rotor (2) and refrigerator rotor (4) have wedges (17, 18) that double as pistons and are balanced by weights (19, 20). Rotor (3) of regenerator has recess (21) for passage of said wedges (17, 18), balanced by recess (22) for passage of loads (19, 20). Engine is configured to control the change in the volume of compression and expansion chambers (8, 5) depending on the rotor turning angle from 90° up to 180° and duration of working stroke.

EFFECT: higher efficiency, power output and longer life of the engine.

1 cl, 15 dwg

Description

Field of technology

The invention relates to engine building, namely to external combustion engines. The engine is intended for installation on smoke stacks and air intake ducts, in medium and low-power boilers as a regenerator with associated electricity generation by driving an electric generator. State of the art: The closest analogues of the author's invention are a rotary internal combustion engine patented under No. DE 202004014 209 U1 dated 02/24/2005 and an internal combustion engine patented in Russia under No. RU 2539412 C1 dated 01/20/2015. The design proposed by the author differs from rotary Stirling engines by the presence of: rotating heat exchange surfaces of a rotor-heater and a rotor-cooler implementing invention No. RU 2130156 C1 dated 05/10/1999; two cylinders for connecting one to the flue duct (rotor-heater), the other to the air intake duct for combustion (rotor-cooler), the presence of a rotor-regenerator, which in turn has reduced hydraulic resistance, and most of the dead volume is involved in heat exchange processes, the surface of the rotor-regenerator cylinder always moves countercurrent to the heated/cooled working fluid; the engine can change the volumes of the working chambers of both the rotor-heater, and the rotor-cooler, and the rotor-regenerator.

The author's invention also differs from its analogues by the presence of three rotors, each of which is a working wheel placed in a cylinder of the same height along its entire length, the working wheels are synchronizedly connected to each other by gears to maintain the phase of the working strokes; the working wheels are located on magnetic bearings, therefore, they have no mechanical friction; there are no sliders with rotating shoes and blades.

The peculiarity of the engine is that all its rotating parts have linear speeds and, as a result, inertial forces are reduced to a minimum. The design of the rotary engine is remarkable in that if the rotor shafts rotate at a constant peripheral speed (i.e. the engine maintains stable revolutions), therefore, all its elements move without acceleration and braking at a constant speed absolutely linearly. This mechanism can be considered close to ideal. None of the rotary and piston external combustion engines of known designs have such characteristics. In all previously known designs there were elements that, at a constant speed of the main shaft, moved with acceleration and deceleration.

In the invention proposed by the author, none of the elements performs reciprocating motion, and the coupled rotors, rotating synchronously, two rotors clockwise, one - counterclockwise, with their surfaces together with the housing, form four chambers of variable volume, perform the opening and closing of the inlet and outlet process windows at the required time. The process window located between the rotor-heater and the recuperator connects the cylindrical part of the expansion chamber (5) with the chamber (7) for heating the working fluid (the cavity of the rotor-regenerator). Another process window is located between the rotor-cooler and the recuperator, connecting the chamber (8) of compression of the working fluid with the chamber (7) for heating the working fluid (the cavity of the rotor-regenerator). The suction of the working fluid into the expansion chamber (5) of the rotor-heater cavity from the compression chamber (8) of the rotor-cooler cavity occurs through the heating chamber (7) (the cavity of the rotor-regenerator), the energy obtained from the expansion of the working fluid is converted into a rotational moment on the shafts and the movement of the heated working fluid from the previous cycle through the rotor-regenerator into the chamber of the rotor-cooler for compression - the subsequent cycle. The engine proposed by the author is simpler, more practical in use, has a smaller mass and is easy to manufacture in contrast to analogues.

Disclosure of invention

The rotary external combustion engine consists of a housing (1) with chambers: expansion (5), cooling (6), heating (7) and compression (8) of the working fluid, each of which is made in the form of three intersecting, identical cylinders, the distance between the centers of which is equal to the sum of the radii of the small rotor-heater/rotor-refrigerator and the large cylinder of the rotor-regenerator, the expansion chamber (5) of the heater cavity has an inlet process window connected to the heating chamber (7) of the regenerator cavity, the compression chamber (8) of the refrigerator cavity has an outlet process window connected to the heating chamber (7) of the regenerator cavity, three rotors are placed in the housing, fixed on three stators located in the center, one in the heater cavity, the second in the refrigerator cavity and the third in the regenerator cavity, synchronized using paired gear parts articulated with each other, while the rotors have the shape of cylinders, and rest against each other with their side parts with the possibility of sealing, the small cylinder The rotor-heater/rotor-cooler rests against the large cylinder of the rotor-regenerator.

In order to increase the efficiency and power/weight ratio of the engine, four complete strokes are provided (suction and heat supply, expansion (working stroke), heat removal, compression) in one 360° revolution of the shafts;

- the engine does not have parts that perform reciprocating movements and are rigidly connected to the working element;

- in order to increase the efficiency, the completeness of the expansion of the working fluid depending on the temperature difference: flue gases in the chimney and supply air in the air duct, it is possible to regulate the change in a large range of the volume of the working chambers: compression and expansion depending on the angle of rotation of the rotors (from 90 degrees to 180 degrees) and the duration of the working stroke; the ratio of the area of the working surface of the rotor to the area of the inner surface of the combustion chamber, necessary for the operation of the external combustion engine, is maintained; there are no places of intense friction in the engine;

- the engine design is simple, the number of parts is minimal, the parts have a simple design; The engine operation scheme proposed by the author will increase the efficiency, power and durability of the engine, as well as reduce engine production costs.

Brief description of the drawings

The external appearance, internal structure and operating principle of the engine are shown in the drawings in Fig. 1-11, which show the complete operating cycle of the engine of the "Stirling engine" type: suction of the heated working fluid from the regenerator and heat supply, expansion (working stroke), preliminary heat removal in the regenerator cavities, heat removal and compression, transfer of the working fluid into the regenerator for preliminary heating before feeding into the expansion cavity for the next cycle.

The engine drawings are shown in Fig. 1-8 in the form of cross-sections. The engine sections are made in the form of a cutting plane that runs perpendicular to the axes of rotation of the cylinders. The sections are highlighted in Fig. 10-11 and designated by numbers 1-1, the arrows show the direction of movement of the rotors.

Fig. 1-8 shows the working stroke of the engine in degrees of movement of the heater/cooler rotors.

Designations on drawings

The proposed external combustion engine comprises a housing (1) with four chambers, each of which is made in the form of three intersecting cylinders the distance between the centers of which is equal to the sum of the radii of two adjacent rotors (2, 3, 4), with an expansion chamber (5) in the heater cavity, with a cooling chamber (6) and a heating chamber (7) in the regenerator cavity, with a compression chamber (8) in the refrigerator cavity, with a process window connecting the compression chamber (8) with the heating chamber (7) for heating the working fluid before feeding it into the expansion chamber (5), made in the form of a segmented cutout (9, shown in purple in the figures) in the side parts of the refrigerator rotor (4), with a process window connecting the heating chamber (7) for heating the working fluid after the compression chamber (8), made in the form of a segmented cutout (10, shown in purple) in the side parts of the heater rotor (2), with two tubes for bypassing the working fluid from the compression chamber (8) to the working fluid heating chamber (7) (11, see Fig. 11) having openings (13 and 14), with two tubes 12 (see Fig. 11) for bypassing the working fluid from the chamber (7) for heating the working fluid of the regenerator cavity to the chamber (5) for expanding the heater cavity (having openings (15 and 16). The heating rotor has a wedge (17) acting as a piston, balanced by a load/counterweight (19) on the opposite side. The cooling rotor, similarly, has a wedge (18) acting as a piston, balanced by a load/counterweight (20), balanced on the opposite side. The regenerator rotor has a recess (21) in its cylindrical part for passing the wedges (17, 18) during rotation, balanced by a recess 22, used to pass the loads (19, 20) during rotation. Two covers (23, 24) located at the ends rotors that have gas end seals (28). Each rotor has toothed rims: a refrigerating rotor (25), a regenerating rotor (26), and a heating rotor (27). The design of the rotating elements of the engine is located on magnetic bearings (not shown in the figures).

Fig. 1 shows the working stroke of the wedge (17) at the 0° position, where the working fluid in the compression chamber (8) is compressed for transfer to the heating chamber (7) of the regenerator cavity.

Fig. 2 shows the working stroke of the wedge (17) at a position of 45°. The remainder of the working fluid passes from the compression chamber (8) to the heating chamber (7) and then to the expansion chamber (5) for subsequent expansion, performing useful work.

Fig. 3 shows the working stroke of the wedge (17) at the 90° position. The working stroke occurs due to the expansion of the working fluid in the heating rotor (2), a new cycle of compression of the working fluid will begin in the cooling rotor (4), and accordingly the working stroke.

Fig. 4 shows the working stroke of the wedge (17) at the location of 135°. The rotor-heater (2) and the rotor-cooler (4) each perform a working stroke. In this case, the heated working fluid in front of the wedge/piston (17) moves into the space behind the stroke of the wedge/piston (18), passing the wall of the rotor-regenerator (3), cooling from it.

Fig. 5 shows the working stroke of the wedge (17) at the 180° position. The working stroke continues. The wedge of the refrigerating rotor (18) creates a partial "vacuum" region after itself, which further facilitates the movement of the working fluid. The process window will soon close: the segment cutout (10), moving clockwise, will close the opening (16).

Fig. 6 shows the working stroke of the wedge (17) at the location 225°. Continuation of the working stroke in the rotor-heater (2) and in the rotor-cooler (4). Soon, when the segment cutout (9) passes through the opening (13), the process window will open, but the working fluid will not be bypassed from the compression chamber (8) to the heating chamber (7). The opening (16) for feeding the working fluid to the expansion chamber (5) has closed.

Fig. 7 shows the working stroke of the wedge (17) at the location 270°. The working stroke continues. The technological window of the hole (13) has opened.

Fig. 8 shows the working stroke of the wedge (17) at the location 315°. The working stroke of the wedge/piston (17) will soon end, and a large flow of heated working fluid will occur in the opened expansion chamber (5) into the compression chamber (8) for subsequent compression by the piston (18).

Fig. 9 shows a front view of the engine.

Fig. 10 shows the left view of the engine.

Fig. 11 shows a top view of the engine.

Fig. 12 shows the right side view of the engine.

Fig. 13 shows a combined arrangement of three cavities: heaters, refrigerators, regenerators of one engine, having one toothed ring on each rotor.

Fig. 14 shows the working stroke of the wedge (17) at the location of 315° rotation of the refrigerating rotor relative to the heating rotor. The engine has reduced compression and expansion chambers, which are approximately 1 to 3 (one part of the cold air expands 3 times) in contrast to the previous case (1 to 4). For example, this is due to the fact that the air at the inlet will have a temperature of 30°C having a density of 1.165 kg/ ^m3 (corresponding to a specific volume of V=0.858 ^m3 /kg), at the outlet the flue gases can heat the working fluid (air) to 800°C having a density of 0.33 kg/ ^m3 , (corresponding to a specific volume of V=0.304 ^m3 /kg).

Fig. 15 shows the working stroke of the wedge (17) at the 180° position of the engine with reduced compression chambers (8) and expansion chambers (5), which are approximately 1 to 2 (one part of the cold air expands 2 times). For example, this is due to the fact that the air at the inlet will have a temperature of 30°C having a density of 1.165 kg/ ^m3 (corresponding to a specific volume of V=0.858 ^m3 /kg), at the outlet the flue gases can heat the working fluid (air) up to 350°C having a density of 0.567 kg/ ^m3 (corresponding to a specific volume of V=1.765 ^m3 /kg).

Claims (1)

A rotary external combustion engine consisting of a housing with cavities formed by three rotors, each of which is made in the form of three intersecting cylinders of the same length, the distance between the centers of which is equal to the sum of the radii of the cylinders of two rotors, said cavities are a heater cavity, a regenerator cavity and a refrigerator cavity, in which an expansion chamber, a cooling chamber, a heating chamber and a compression chamber are formed, the heater rotor has an inlet process window, the refrigerator rotor has an outlet process window, wherein the process windows connect the heating and cooling chambers of the regenerator cavity with the compression chamber of the refrigerator cavity and with the expansion chamber of the heater cavity, two of the three rotors are identical and synchronized with the help of paired toothed wheels articulated with each other, the rotors rest against each other with their side parts with the possibility of sealing, and also each rotor performs the function of a heat exchange wall, wherein the heater rotor and the refrigerator rotor have a wedge that acts as a piston and is balanced by a load on the opposite side of the rotors, and the regenerator rotor has a recess for passing said wedges, balanced by a recess on the opposite side for passing the loads of the heater and refrigerator rotors, in addition, the engine is designed with the ability to regulate the change in the volume of the compression and expansion chambers depending on the angle of rotation of the rotors from 90° to 180° and the duration of the working stroke.