JPS63262075A - Discharge gas heat thermoelectric conversion generator - Google Patents

Abstract

PURPOSE:To obtain a large power by forming the discharge gas passage wall of a high temperature side heat absorbing section in a columnar shape to increase the heat absorbing efficiency. CONSTITUTION:A discharge gas heat thermoelectric conversion generator is composed of a heat absorber 1, a liquid cooling jacket 2, a coolant pipe 3, an exhaust gas inlet 4 and outlet 5, a thermoelectric converter unit 6, a voltage regulator, a current reverse flow preventing unit 7, a power meter 8, and a storage battery 9. In this case, a fin 10 is provided to efficiently perform a thermal exchange in the absorber 1 for thermally exchanging while passing discharge gas. Thus, it can be made compact, have good generating efficiency, and can be mounted at any position of the passage.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an exhaust heat thermoelectric conversion generator that utilizes the heat of waste (exhaust) gas, and particularly to an exhaust heat thermoelectric conversion generator that utilizes the heat of exhaust gas from an internal combustion engine such as an automobile. It is an exhaust heat thermoelectric conversion generator.

[Prior Art] Thermal energy of exhaust gas from factories and exhaust gas from internal combustion engines such as automobiles is usually released as is. However, in recent years, we are heading into an era of energy conservation, and research into utilizing the heat of exhaust gas has become active.

Exhaust heat thermoelectric conversion generators use thermoelectric conversion elements to directly convert the thermal energy of exhaust gas into electrical energy, which is then used as electrical energy, and is attracting attention as a means of energy conservation.

Several patents have been issued so far, but the
44842, Japanese Patent Publication No. 61-254082, etc., the voltage and power are low, and as will be described later, it can be said that they are insufficient especially for use in automobiles.

[Problems to be Solved by the Invention] In an exhaust heat thermoelectric conversion generator using a thermoelectric conversion element, in order to efficiently bring out the performance of the thermoelectric conversion element, the following formula Z = α2 / ρ, Z = figure of merit (10'/'C) α=Voltage (V/'C) ρ=Resistance
(Ω/cm) = Thermal conductivity (W m / °C) Since ρ is determined by the material, α must be made large. Since α is a value determined by the temperature difference IT), 4T=(Th −Tc) −T=temperature difference Th=temperature on the high temperature side Tc−temperature on the low temperature side, −T must be set large.

From the above point of view, the proposals in each of the above-mentioned publications are unreasonable in terms of methods and structures in order to fully bring out the performance of the thermoelectric conversion element.

For example, in Japanese Patent Publication No. 58-44842, it is good to use fins to absorb heat, (heat exchange), and dissipate heat (heat removal), but due to the structure, the installation is limited to the vicinity of the exhaust gas outlet, and the temperature of the exhaust gas is Since it is located at a fairly low location, it is extremely difficult to apply a large temperature difference to the thermoelectric conversion element.

Further, in Japanese Patent Publication No. 61-254082, the heat absorbing portion on the exhaust gas passage side is smooth and is disadvantageous in heat absorption, and in addition, the cooling side heat dissipating surface is also flat and has a small heat dissipating area. Therefore, the amount of heat from the exhaust gas passing through the thermoelectric conversion element is small, and it can be said that this is an impossible structure to obtain a large amount of electric power.

The present invention is based on a thorough knowledge of the characteristics of thermoelectric conversion elements, and utilizes exhaust gas efficiently to generate a large temperature difference and a large amount of heat flow, thereby obtaining large amounts of electric power.

Furthermore, the present invention takes into account the conventional disadvantages and provides a reasonable method,
The purpose of the present invention is to provide an exhaust heat thermoelectric conversion generator that utilizes the heat of exhaust gas, ensuring a large temperature difference and a large amount of heat flow through its structure, and fully and efficiently utilizing the performance of thermoelectric conversion elements.

[Means for Solving the Problems] ゛The present invention provides a column-shaped,
The heat absorption efficiency has been increased by ingenuity in the shape and structure of fins, honeycombs, etc., and the low-temperature side cooling section that collects the heat that has passed through the thermoelectric conversion element has been made into a liquid cooling jacket, and a liquid with a high specific heat is used. By improving the efficiency of heat removal through this process, it became possible to flow a large temperature difference and a large amount of thermal energy to the thermoelectric conversion element, thereby obtaining a large amount of electric power.

In particular, the above object is achieved by adopting a reasonable method and structure that can secure the electric power necessary for vehicle operation even when installed in a vehicle.

This will be explained below using the drawings.

FIG. 1 shows an exhaust heat thermoelectric conversion power generator system of the present invention, and the area within the dotted line indicates the exhaust heat thermoelectric conversion power generator of the present invention.

1 is a heat absorption part, 2 is a liquid cooling jacket, 3 is a cooling water pipe, 4 is an exhaust gas inlet, 5 is an exhaust gas outlet, 6 is a thermoelectric conversion element unit, 7 is a voltage regulator and a current backflow preventer, 8 is a power meter, and 9 is a storage battery.

The exhaust heat thermoelectric conversion generator of the present invention has a heat absorption part that exchanges heat while passing the exhaust gas as shown in FIGS. 2 and 3.
has been established.

When the heat absorbing parts shown in FIG. 2 are overlapped, the heat absorbing parts interlock with each other, allowing exhaust gas to pass through the inside.

Next, as shown in FIG. 4, a thermoelectric conversion element that directly converts thermal energy into electrical energy is made by arranging p-type and n-type 12 alternately through electrodes 11, and 70 Alumina plates were bonded to the top and bottom surfaces as electrical insulators.

Note that the combined number of p-type and n-type 12 in one unit can be any number from several to over 100.

The thermoelectric conversion elements made into units are arranged in 10 units on one plane as shown in Fig. 5, and electrically connected in series from the electrical terminal of each unit (Fig. get. Note that any number of units may be used depending on the purpose.

FIGS. 6 and 7 show the above-described unit thermoelectric conversion element 6 sandwiched between the heat absorbing part 1 and the cooling part 2.

The cooling section is a liquid cooling jacket having a jacket shape 2 as shown in FIG. 8 and provided with passages 14 through which cooling water or hot water flows.

[Function] The members constituting the exhaust heat thermoelectric conversion generator are roughly divided into a heat absorption section, a cooling section, and a power generation section.

The heat absorbing part is placed in a part of the exhaust gas passage using a material with good thermal conductivity, and the structure is such that there is enough space between the exhaust gas and the heat absorbing part, such as columnar, fin, or honeycomb, to efficiently absorb heat from the exhaust gas. To enable proper heat exchange.

The cooling section is a jacket made of a material with good thermal conductivity, and a passage is provided in the middle layer of the jacket to allow a sufficient amount of liquid to pass through, allowing the liquid with a large specific heat to pass through for efficient cooling.

The power generation section consists of tens to hundreds of thermoelectric conversion elements, p-type and n-type, arranged alternately through electrodes, arranged thermally in parallel and electrically in series. Decide and use the number of units depending on the situation.

Each part is assembled to form an exhaust heat thermoelectric conversion generator, and the power generation part is sandwiched between the heat absorption part and the cooling part, and the parts are assembled so that there is no gap between the combined contact surfaces of the parts. If there is a gap, it is recommended to use a combination band with good thermal conductivity.

The present invention created as described above is much more compact than conventional products, has better power generation efficiency, and can be installed at any position in the exhaust gas passage. When used in an internal combustion engine, it is preferably located close to the internal combustion engine, and depending on how it is used, it can also serve as part of a muffler.

In addition to the above, when the present invention is used as a generator for an automobile, it is preferable to use it together with a storage battery, and it is desirable to attach a voltage regulator and a current backflow preventer to the power extraction side of the present invention.

Engine cooling water may be used as the cooling liquid, and even if the temperature of the cooling water rises during use, the power generation function of the exhaust heat thermoelectric conversion generator of the present invention will not be impaired.

Therefore, it can be used as an auxiliary or alternative generator for an alternator-generator that utilizes the rotational power of a current automobile engine. In particular, if used as a replacement for the currently used automobile generator alternator, the energy required for power generation out of the engine output will be unnecessary and all of the engine output can be used for driving force, leading to improved driving performance and additional This has the great advantage of contributing to fuel savings as it utilizes exhaust heat.

The application of the present invention is, of course, not limited to the use of exhaust heat from automobiles, but can be widely applied to the use of waste (exhaust) heat generated from general factories.

[Example] An example using the exhaust heat thermoelectric conversion generator of the present invention illustrated in the drawings will be described below.

For heat absorption, hot air is blown from the exhaust gas port 4 in FIG.

For cooling, hot water whose temperature was adjusted to 60° C. in a constant temperature water bath was sent to the liquid cooling jacket 2 through the pipe 3, and the hot water that had passed through the liquid cooling jacket 2 was returned to the constant temperature water bath and used for circulation.

Unit 6 of thermoelectric conversion elements was carried out using a total of 20 units, 10 on each side.

The results are that the temperature difference (iT) given to the thermoelectric conversion element is: 43W when JT = 70°C 95WΔT = 11 when T = 100°C
A power of 131W was obtained at 7°C.

[Effects of the invention] The present invention improves the effect of utilizing exhaust heat from exhaust gas and uses a water-cooling system for the heat extraction section, making it an excellent product that is compact and has a large power generation capacity, making it ideal for mounting on automobiles. An exhaust heat thermoelectric conversion generator can be provided.

Furthermore, the present invention makes it possible to effectively utilize waste heat of exhaust gas from general factories.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of the present invention, Fig. 2 is a plan view of an example of a heat absorption part, Fig. 3 is a side view of Fig. 2, Fig. 4 is a schematic diagram of thermoelectric conversion elements as a unit, and Fig. 5 is an explanatory diagram of how to use the unit of the present invention, FIG. 6 is a schematic diagram showing a state in which the heat absorption section, power generation section, and cooling section of the present invention are combined, FIG. 7 is a front view of FIG. 6, and FIG. 8 is a schematic diagram of a liquid cooling jacket. 1... Heat absorption part 2... Liquid cooling jacket 3... Cooling water pipe 4... Exhaust gas population 5
... Exhaust gas outlet 6 ... Thermoelectric conversion element unit 7 ... Voltage regulator and current backflow preventer 8 ... Power meter 9 ... Storage battery 10 ...
・Fin 11... Electrode 12... Thermoelectric conversion element (p type, n type) 13... Electrical terminal
14... Cooling water inlet/outlet condition Attorney Tatsuo Chanoki, patent attorney Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Claims] In an exhaust heat thermoelectric conversion generator consisting of a thermoelectric conversion element that converts thermal energy into electrical energy, a heat absorption section that absorbs heat energy of exhaust gas, and a heat removal side cooling section that removes heat, the heat absorption surface of the heat absorption section on the exhaust gas passage side has a columnar, fin-shaped or honeycomb-like structure, the heat extraction side cooling section has a liquid cooling jacket structure, and the heat absorption section is stacked and fixed with a thermoelectric conversion element and a heat extraction side cooling section. Thermal thermoelectric conversion generator.