JPH03160274A - Heat storage device - Google Patents

Abstract

PURPOSE:To make it possible to provide excellent heat transmission and high output by forming a heat storage vessel which is directly connected with a heat pipe through which a heat medium passes, comprising a heat storage device built in with a specific heat storage body and electric heater inside said heat storage vessel, and bringing said heat medium into direct contact with the heat storage body. CONSTITUTION:A heat storage body 1 is green compacts filled up with fine particles 1a in a vessel 1b. A flow passage 1c is formed wherein a working fluid which is a heat medium, such as water passes through. An electric heater 3 is airtight-mounted so that a heating element may be exposed inside a heat storage vessel while its terminal may be exposed outside. It is sheathed with stainless steel. When a working fluid, such as water as a heating medium is supplied from a liquid pipe 4 installed below the heat storage vessel 2, the working fluid is heated by the heat of the heat storage body 1 so that it may be turned into steam and ejected from a steam pipe 5 located above, which makes it possible to take out the heat of the heat storage body 1. In this case. Since the working fluid is brought into direct contact with the heat storage body 1, it is possible to maintain heat transmission to a satisfactory extent. A sphere shaped body is adopted as the heat storage body 1. Furthermore, it is necessary to use the heat storage body 1 whose diameter is 20mm and smaller so as to fill up with high density.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an electric heat storage device used in water heaters and the like.

[Conventional technology]

Heat storage technology, which stores heat in an object with a large specific heat and uses this sensible heat later, has been widely known and used in a variety of fields.

For example, hot water storage type water heaters that directly heat water and use the water itself as a heat storage body have been widely used as water heaters that utilize heat storage from electrical energy. In addition, the present applicant has already proposed the use of non-oxide ceramics as a heat storage material for a smaller, higher-performance heat storage device (
(Patent Application No. 180594/1983, No. 63-180595)
. This is a heat storage body made of non-oxide ceramics such as silicon carbide ceramics and silicon nitride ceramics, which is equipped with an electric heater and a heat pipe, and the electric heater stores heat in the heat storage body. The heat pipe was used to extract this heat when necessary.

[Issues with conventional technology]

However, in the heat storage device using non-oxide ceramic ξ NOCS as described above, the structure is such that a heat pipe is sandwiched between the heat storage body made of ceramic ceramic, and a small space is created between the two, which hinders heat transfer. There is a problem in that not only is this hindered, but also distortion occurs due to the difference in thermal expansion between the heat storage body and the heat pipe.

In addition, if the heat medium flow path is directly drilled into the heat storage element, heat transfer will be good, but in order to increase the heat transfer area and increase the heat output, it is necessary to drill many flow paths. First, there was a problem in that manufacturing was extremely difficult.

As described above, in the conventional heat storage device using ceramics, it is difficult to improve heat transfer between the heat storage body and the heat pipe and to achieve high output.

[Means to solve the problem]

In view of the above, the present invention constitutes a heat storage device by forming a heat storage container directly connected to a heat pipe through which a heat medium passes, and housing a heat storage body and an electric heater in the heat storage container. It is designed to come into direct contact with the heat storage body.

〔Example〕

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

The heat storage device T shown in FIG. 1 has a heat storage body 1 filled with powder and an electric heater 3 built into a heat storage container 2 made of stainless steel. The heat storage container 2 is directly connected to a liquid pipe 4 on the lower side and a steam pipe 5 on the upper side, and these liquid pipes 4 and steam pipes 5 collectively constitute a loop-shaped heat pipe H, and the heat pipe H passes through the heat storage container 2. The heat medium passes through the heat storage container 2 and comes into direct contact with the heat storage body 1.

The heat storage body 1 is a compacted powder body in which powder 1a is filled in a container lb, and has a flow path 1c through which a working fluid such as water as a heat medium passes, and is further shaped into a small block. It is divided to increase the heat transfer area and improve operability. In addition, the electric heater 3 has a heat generating part inside the heat storage container 2,
It is installed airtight so that the terminal part is exposed to the outside, and is sheathed with stainless steel.

Heat is stored in the heat storage device T by energizing the electric heater 3 to generate heat, heating the heat storage body 1, and storing the heat as sensible heat. When taking out the heat stored in this way, when a working fluid such as water is supplied as a heat medium from the liquid pipe 4 below the heat storage container 2, the working fluid is heated by the heat of the heat storage body 1 and becomes steam. By spewing out from the upper steam pipe 5,
Heat from the heat storage body 1 is extracted. In this case, since the working fluid is in direct contact with the heat storage body 1, it is possible to maintain extremely good heat transfer.

Further, as shown in Table 1 below, the powder used as the heat storage body 1 may be a powder of ceramics, metals, ores, and has an average particle size in the range of 1 to 500 μm, especially at 500°C. The amount of heat stored per unit volume is 3 when heat is stored in
00 kcal/E or more, thermal conductivity is 0.4 kc
al/m ・h -K or higher was excellent.

[Margin below]

Next, another embodiment of the present invention will be described.

The heat storage device T shown in FIG. 2 has a heat storage body 1 and an electric heater 3 built into the heat storage container 2 as in the previous embodiment, and a liquid pipe 4 and a steam pipe 5 constituting a heat pipe H are connected to the heat storage container 2, respectively. The heat medium passing through the heat pipe H comes into direct contact with the heat storage body L.

In this embodiment, a spherical body is used as the heat storage body 1, and the voids are reduced by mixing two or more types of spherical bodies with different diameters.
It is desirable to use one with a diameter of 0 mm or less. Further, as the material of this heat storage body 1, ceramic ξ as shown in Table 2 below is used.

[Margin below]

This heat storage device T stores heat as sensible heat in a heat storage body 1 by energizing an electric heater 3, and when a working fluid as a heat medium is supplied from a liquid pipe 4, the working fluid is heated by the heat storage body 1. The heat from the heat storage body 1 is taken out by evaporating and turning into steam and ejecting it from the steam pipe 5.

At this time, since the working fluid is in direct contact with the heat storage body 1, heat transfer is extremely good, and since the working fluid passes through the gaps between the spherical heat storage bodies 1, the heat transfer area can also be increased. In addition, since ceramics are used as the heat storage body 1, it is light and has excellent heat storage capacity and corrosion resistance.Moreover, the heat storage body 1 is easy to manufacture because the heat storage container 2 is simply filled with spherical bodies. There is also little thermal distortion.

Next, a water heater using the heat storage device T of the present invention will be explained.

As shown in FIG. 3, the steam pipes 5 and liquid pipes 4 of the heat storage device T are connected to the heat exchanger 7, forming a loop-shaped heat pipe H as a whole, and the heat storage device T and the steam pipes 5 are heat-insulated. Covered with material 6. Further, a working fluid 9 which is a heat medium is sealed inside the heat pipe H after being evacuated, and by opening the heat pipe valve 8, the working fluid 9 can be supplied to the heat storage container 2 through the liquid pipe 4. It looks like this.

First, sensible heat is stored in the heat storage body 1 using the electric heater 3, and when the heat pipe valve 8 is opened when hot water is required, the working fluid 9 is supplied into the heat storage container 2, and is evaporated by the heat of the heat storage body 1. The fluid 9 is guided to the steam pipe 5 on the low pressure side. This air is condensed in the heat exchanger 7 and guided to the liquid pipe 4 again, but the heat of condensation is transferred to the water in the water pipe 10 in the heat exchanger 7, and hot water can be generated.

Here, we actually produced a prototype of the heat storage device T shown in Fig. 2, and
A usage test was conducted using the water heater shown in the figure. heat storage body l
using alumina ceramics as the diameter 20 llu
Three types of spheres, ++, 10 mm, and 0.2 mm, were mixed at a ratio of 64:25:10 and filled into the heat storage container 2. As a result, the heat storage body 1 was brought into a close-packed state, the total volume of the heat storage container 2 was 161, the volume of the heat storage body 1 was 15 l, and the porosity was 6%.

Further, four electric heaters 3 were used, which were sheathed with stainless steel and had a heat output of 400 W.

Furthermore, the heat storage device T has a thermal conductivity of 0.02 kcal/m.
- Covered with insulation material 6 below hK.

In this heat storage device T, when electricity is applied to the electric heater 3, 5
After an hour, the heat storage body 1 is uniformly heated to 500℃ and 6
000 kcal of heat was stored. Thereafter, the heat viper valve 8 was opened, and the hot water obtained was 400 kcal/min. In other words, it is possible to raise the temperature of 161 water by 25°C in 1 minute.
It was able to demonstrate the same performance as a typical No. 16 gas instantaneous water heater for home use.

〔Effect of the invention〕

As described above, according to the present invention, the heat storage device is constructed by incorporating the heat storage body and the electric heater in the heat storage container directly connected to the heat pipe, so that the heat medium passing through the heat pipe is directly connected to the heat storage body. Because it comes into contact with the metal, it has excellent heat transfer, and the heat transfer area can be increased, allowing for high output. Further, since the heat storage body is simply filled with powder or spherical bodies, it is possible to provide a heat storage device having various features such as easy manufacture and no thermal distortion.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway exploded perspective view showing a heat storage device according to an embodiment of the present invention, and FIG. 2 is a sectional view showing another embodiment of the present invention. FIG. 3 is a schematic diagram showing a water heater using the heat storage device of the present invention. 1: Heat storage body 2: Heat storage container 3: Electric heater 4: Liquid pipe 5: Steam pipe T: Heat storage device

Claims (3)

[Claims] (1) A heat storage device characterized in that a heat storage container is directly connected to a heat pipe through which a heat medium passes, and a heat storage body and an electric heater are built in the heat storage container. (2) The heat storage device according to claim 1, wherein the heat storage body is a powder. (3) The heat storage device according to claim 1, wherein the heat storage body is a spherical body having a diameter of 20 mm or less.