JPS5882049A - Stirling engine - Google Patents

Abstract

PURPOSE:To increase the output and the thermal efficiency of a Stirling engine, by forming a combustion-air inlet passage between a heat-insulating member at the bottom of a combustion chamber and a cooler block surrounding compression chambers, and recovering heat leaked through cylinder walls by combustion air. CONSTITUTION:Combustion air is introduced from a lower portion of a cooler block 6 and carried into a combustion-air inlet passage 16 via a central inlet port 18. Then, the combustion air is delivered radially outwards. Here, since cylinders 2 are exposed partially to the air inlet passage 16, heat in a combustion chamber 12 is transmitted through the walls of the cylinders 2. However, the heat thus transmitted through the cylinder walls is absorbed by combustion air in the air inlet passage 16, so that transmission of heat to compression chambers 5 constituting low-temperature sections of the cylinders 2 can be minimized. Further, since the load of an air preheater 9 disposed around the combustion chamber 12 and transmission of heat to cooling water 7 are both reduced by the recovery of heat by the combustion air, it is enabled to reduce the size of the heat radiating section of a cooler 15.

Description

[Detailed Description of the Invention] This invention relates to a Stirling engine, and in particular,
By improving the combustion air introduction path, the working gas consisting of horns or a mixture thereof is passed between the expansion chamber, which is a high temperature section, and the compression chamber, which is a low temperature section, via a heater, a heat storage device, and a cooler 2. It moves back and forth to extract mechanical work to the outside. Maintaining the temperatures of the high temperature section and the low temperature section at predetermined values is important for stabilizing the output of the Stirling engine. For example, heat leakage from the high-temperature section to the low-temperature section through the walls of the cylinder that forms the expansion and compression chambers lowers the temperature of the high-temperature section and increases the temperature of the low-temperature section, causing a reduction in the output of the Stirling engine. It becomes. Furthermore, the leaked heat is released to the atmosphere through the radiator, reducing the thermal efficiency of the engine.

This invention allows combustion air to flow along the outer wall of the cylinder,
Another object of the present invention is to provide a Stirling engine in which the combustion air is supplied into the combustion chamber to recover the heat transmitted through the cylinder wall, thereby preventing the leakage of heat from the high-temperature section to the low-temperature section. shall be.

Embodiments of the invention will be described with reference to the accompanying drawings.

A plurality of cylinders 2 of a Stirling engine 1 are arranged concentrically, and within the cylinders 2, an expansion chamber serving as a high temperature section and a compression chamber 5 serving as a low temperature section are defined by a piston 3. A cooler block 6 is arranged around the compression chamber 5. Cooling water 1 is caused to flow into cooler block 6. The good heat collected in the cooling water 7 is
Heat is radiated by a radiator (not shown). The combustor 8 is
It has an air preheater 9 around it and a fuel atomizer 10 in the center of the top. A heat insulator 11 is provided at the bottom of the combustor 8, and a heater 14 communicating with the expansion chamber 4 and the heat storage device 13 is arranged within the combustion chamber 12. The heater 14 receives the combustion heat, heats up the working gas therein, supplies it to the expansion chamber 4 , and also functions to recover the working gas from the expansion chamber 4 to the heat storage device 13 . The heat accumulator 13 is communicated via a cooler 215 with cooling water 7 to the compression chamber 5 of the adjacent cylinder.

A combustion air introduction path 16 is formed between the heat insulator 11 and the cooler block 6. Fins 17.17 are provided on the outer walls of the cylinder 2 and the heat storage device 13 exposed to this air introduction passage 16.
' is provided.

The air inlet 16 has an inlet 18 drilled through the center of the cooler block 6 and an outlet 19 leading to an air preheater 9 around the combustor 8 .

In the above-described configuration, combustion air is introduced from below into the cooler block 6, enters the combustion air introduction passage 16 through the central inlet 18 of the cooler block 6, and flows uniformly outward in the radial direction p1. At this time, since a part of the cylinder 2 is exposed to the air introduction passage 16, even if the high temperature of the combustion chamber 12 is transmitted through the wall of the cylinder 2, this heat is
The combustion air in the air introduction passage 16 is recovered and the cylinder 2
Heat transfer to the compression chamber 5, which is on the low temperature side, is minimized. Furthermore, this heat recovery by air reduces the burden on the air preheater 9 around the combustion chamber 12, and also reduces heat transfer to the cooling water 7, making it possible to downsize the heat dissipation section of the cooler 15. 4 From the perspective of practical soil, since an air layer with a high heat insulation effect is formed between the combustor 8 and the cooler block 6, heat transfer due to radiation from the combustor 8 side to the cooler block 6 is reduced. , the temperature rise of the cooler block 6 can be suppressed to a minimum.

As is clear from the above, according to the present invention, a combustion air introduction path is formed between the heat insulator at the bottom of the combustor and the cooler block facing it, and the combustion air is introduced from the center of the cooler block. The heat that leaks from the hot section to the cold section through the cylinder wall is absorbed by the air inlet, flows radially outward, and then into the air preheater around the combustor. It can be recovered by combustion air on the road. This improves the output and thermal efficiency of the Stirling engine, reduces the burden on the air preheater, and contributes to downsizing of the heat dissipation section of the cooler. Furthermore, since the air from the air introduction passage uniformly enters the preheater, the entire heat transfer area of the preheater can be used effectively.

[Brief explanation of drawings]

The figure is a partial sectional view of a Stirling engine as an example of the present invention. In the diagram: 1... Stirling engine, 2... cylinder,
3... Piston, 4... Expansion chamber, 5... Compression chamber,
6... Cooling block, 8... Combustor, 9... Air preheater, 11... Insulator, 14... Heater, 15
...Cooler, 16...Air introduction path, 18...Inlet, 19...Outlet. Agent Patent Attorney Hideaki Kuwahara

Claims (1)

[Claims] A cooler block provided around the compression part of a plurality of cylinders, a combustor housing a heater communicating with the expansion chamber of the cylinder and having a heat insulator at its bottom, and between the heat insulator and the cooler block. has nine combustion air introduction passages, the air introduction passage has nine inlets located in the center of the cooler block, and an outlet leading to an air preheater disposed around the combustor; A Stirling engine J characterized in that the combustion air in the air introduction path recovers heat leaked from the combustor through the cylinder wall.