RU1793086C - Engine - Google Patents

Abstract

Usage: energy, in particular, external heat supply engines, work and science-e angle - SAE. .: Matters working on the Stirling cycle. SUMMARY OF THE INVENTION: A Stirling engine comprises at least two pairs of radially arranged cylinders 1-4 located inside each cylinder, one working pistons 5-8, dividing the cylinder volume into two working cavities. Each two pistons in the cylinders are located opposite each other on the same axis and are connected by a common rod 9 and 10. which is connected to the drive mechanism 11. One of the working cavities of each cylinder is made in the form of an expansion cavity, and the other in the form of a compression cavity, and the cavity compression of one cylinder is associated with the expansion cavity of the other cylinder, following it in order of operation, which leads to an increase in engine life. 2 ill. fe

Description

The invention relates to energy, in particular to external heat supply engines operating on a Stirling cycle.

Known Stirling engine (DS), made according to the scheme of A.K. Reeder, in which the hot and cold cavities for the working coolant are divided into 2 cylinders, closed by pistons, and the cavities equipped with a heater and a refrigerator, respectively, communicate with each other through a connecting channel with a built-in regenerator, and the pistons through the drive mechanism, which allows to have an optimal phase angle between their movements, are kinematically connected with the output power removal device.

However, DS according to the scheme of A.K. The rider has a large metal consumption, large dimensions and high cost per unit of productivity, the drive mechanism with complex kinematics consists of many details .. ....: -.This quality limits the range of application of the engines with low power and does not allow economically justified to obtain at the output of more than 15 kW of power,, ......-: ..:.

These shortcomings were eliminated in a double-acting DS with a rodless drive mechanism containing expansion cylinder blocks from compression cylinders, in which the hot cavities of the expansion cylinder are connected in pairs by channels with the corresponding cold cavities of the compression cylinder, and the cylinders of the same name are different (adjacent drive) blocks are placed on common stocks,

As a result, the number of reciprocating moving units is minimized in them in comparison with the DS according to the scheme of A.K. Reader, the number of pistons and drive parts is reduced by 2 times, which greatly simplifies the kinematic scheme of the drive mechanism, reduces metal consumption and reduces the cost of the engine when the same power. .

At the same time, the resource of such an engine will be relatively small, since the results of thermodynamic cycles in the blocked two cylinders are identical to those of the block of the other two cylinders, but they are placed relative to the drive in such a way that the effects of the blocks are shifted on the output shaft 180 angle of rotation of the crank. and since the periodicity of the change of the parameters of the cycles in the cylinders of the block is also 180 ° (starting from the design), then at each moment of time the value

torque from the blocks of paired cylinders, and on the rods twice the value of the axial forces / developed by the pistons in identical cylinders.

In FIG. 1 as an example for a DS with typical parameter values, the functions of changing the torques are shown depending on the rotation angle of the engine output shaft, where 1 is the torque of the prototype (M), 2 is the torque of the expansion cylinder block with the compression cylinder, 3 - torque of the proposed engine, 4 - average value of the engine torque (M).

The magnitude of the torque is the product of the tangential force T and the radius of the crank. In turn, the force T is equal to the product of the forces from the gas pressure on the piston 2 by the tangential component Ti of the axial unit force Rosev applied to the nodal point (A, B of FIG. 2) of the rodless drive mechanism connected to this piston, where

Tl Foceo sfn f 1 “2sin (p 2siny.

As follows from the graphs (Fig. 1, positions 1 and 4), the degree of unevenness of the torque will be approximately

 ,8; .- .-.;

torque non-uniformity coefficient

K2 (Mmax-Mmin), 5;

here Mmzks - the maximum value of torque,

Min is the minimum torque value.

M is the average value of the torque. . . . . -..... -.

Axial forces through the drive mechanism are also transformed into reaction forces; associated with them is directly proportional, in friction pairs; For a rodless power mechanism (BSM), the main friction losses occur at nodal points A and B and are for axial unit force

WA Foceo Sin 2tt; NB Focee-COS2. "

When the forces from the gas pressure are taken into account, changes in the reactions along the angle of rotation of the BSM crank are displayed for the prototype with typical parameters, curves 5 and 6. Representing NA f (y) and NB fi (p), respectively (Fig. 1). Reactions have a pronounced peak character with significant amplitude,

Seals of rods and pistons in hot expansion cylinders present a difficult technical challenge today, since the operating temperature in

„

/ tx reaches values of the order of 700 ° C.

These reasons considered lower the normal operation of the engine.

An object of the invention is to increase engine life.

The goal is achieved in that this double-acting DS with an ECM drive and cylinders, all engine cylinders contain hot expansion cavities and cold compression cavities separated by pistons, and the expansion cavity of the first cylinder is connected to the compression cavity g through heat exchangers next, etc., and the expansion cavity r of the last cylinder through the heat exchange is closed to the compression cavity of the first cylinder.

Figure 2 shows a schematic diagram of the described engine.

The DS has cylinders 1, 2, 3, 4, respectively containing hot cavities of the raziireniya I, III, V. VII, separated by pistons), 6, 7, 8 from the cold compression cavities II, IV, / I, VIII. Pistons are placed on the rods 9, 10 of the BSM 11. The hot expansion cavities I, 111, | /, VII are connected respectively by channels; heat exchangers 12, 13, 14, 15 with cold compression cavities N, IV, VI, VIII,

Consider the operation of one of the cylinders, since all cylinders work identically.

AT

kind of that in commutated

the volume of cavities is the same amount of gas, the greater the pressure will be in the volume where the bulk of the gas is concentrated in the hot cavity — for the initial moment () - in the cavity 1 of cylinder 1 Therefore, the rod 9 will shift to the right by turning the drive mechanism counterclockwise. in view of the dominant

effects of axial force. developed in cylinder 1. In the remaining cylinders, various preparatory and final phases of Stirling cycles, which do not have high pressures and accordingly have little effect on the output torque, pass at this time. After about a quarter of a turn, the situation will repeat in the cavity of the cylinder 2, and the rod 10 will move upward, continue to turn the drive mechanism against h. etc., in all cylinders in the order of Nos. 2,3,4 every 90 ° of turning the BSM crank; in this way; the same amount of energy will be more evenly distributed in time and the output torque will have the form depicted in Fig. 1; position 3, characterized by parameters, 02; , 21. Those. degree. unevenness in comparison with the prototype adopted for the base object will decrease by 3.8 times, and the coefficient of unevenness by 27.5 times. Axial forces will also have lower values and reactions at the nodal points are depicted by curves 7 and 8 - NA fa ((p} and s (- Fig. 1,

peak values are half that of the prototype. The seals of the rods and pistons in the engine of the invention are located in the cold zone and operate under normal conditions.

As a result, the dynamic load of parts subject to the influence of torque is reduced, the load of the main friction pairs is reduced, the design of the seals is simplified, which allows to increase the life of individual components and the entire engine as a whole. The engine starting is also facilitated and the flywheel is not required; aggravating and complicating the design.

45

. -..- Formula and sampling j Stirling engine containing at least two pairs of radially arranged cylinders placed inside each cylinder, one working piston, 1 piston, section the cylinder volume into two working cavities, heaters, regenerators I and refrigerators installed one in each line connecting

an expansion cavity of one cylinder with. compression of another cylinder, and

every two Pistons in cylinders are arranged opposite one another on the same axis and connected by a common rod, which is connected to the drive mechanism, characterized in that, in order to increase the life of the engine, one of the working cavities of each cylinder is made in the form of an expansion cavity, and the other in the form of a compression cavity, the compression cavity of one cylinder being associated with the expansion cavity of the other cylinder following it in order of operation. ...