JPS6362997B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an EHD power generation device, and more particularly to a natural circulation type EHD power generation device configured such that a working fluid is naturally circulated due to a temperature difference.

As the principle of EHD power generation, or electrohydrodynamic power generation, is already well known, corona discharge is performed in the gas at the entrance of the flow path to ionize the gas, and then the gas is ionized by the collector electrode at the exit of the flow path. This is a power generation method that recovers the kinetic energy or pressure energy of the gas as electrical energy by unloading the gas. Conventionally known EHD power generation devices circulate the gas by:
Since a mechanical device such as a pump was required, the structure of the device was complicated, and there were drawbacks such as the need for periodic maintenance of rotating parts such as the pump.

It is an object of the present invention to eliminate the above-mentioned drawbacks, to provide an EHD power generation device that does not require a mechanical device having rotating parts such as a pump, has a simple structure, and has no rotating parts.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In the figure, 1 is an annular sealed casing, and a fluid circulation channel including an upward flow channel 1A and a downward flow channel 1B is built into the closed casing 1. A working fluid such as freon is contained. A heating device 2 for vaporizing the fluid is provided at the lower part of the ascending flow path 1A, and the heating device 2 is heated by a high temperature source supplied from outside the sealed casing 1. The high temperature source is, for example, relatively high-temperature waste gas (which may also be heated wastewater), which is supplied through pipe 3, and the heat retained in the waste gas is recovered through heat exchange. Afterwards, it is disposed of through a discharge pipe 4.

Immediately above the heating device 2, an inlet electrode 6 made of a metal plate with many small holes 5 of about 0.1 mm in size and a net-like or grid-like charging electrode 7 are provided, and a high voltage is applied between the two electrodes. Accordingly, the droplets are configured to be charged using polarization or corona discharge.

On the other hand, a net-like or grid-like collector electrode 8 is provided at the upper position of the upward flow path 1A, that is, at the upper position of the downward flow path 1B.
is electrically connected to the inlet electrode 6 and the charging electrode 7 via an electrical load 9 outside the closed casing 1. Downstream channel 1B of collector electrode 8
A cooling device 10 is provided at an upper position of the casing 1, and the cooling device 10 is cooled by cooling water supplied from a low temperature source outside the sealed casing 1. Cooling water is supplied through a pipe 11, and is discharged through a discharge pipe 12 after cooling a heat medium such as Freon steam.

Next, the general operation of the EHD power generation apparatus of the present invention having the above-mentioned configuration will be explained.

When the working fluid such as freon sealed in the sealed casing 1 is cooled by the cooling device 10, it condenses into a liquid, flows down the downward flow path 1B, and accumulates at the bottom of the sealed casing 1. However, since the working fluid in the lower part of the ascending flow path 1A is heated by the heating device 2, the small hole 5 of the inlet electrode 6
At the same time, a portion of the working fluid is vaporized and reaches the saturated vapor pressure at that temperature. The pressure difference between this pressure and the steam pressure corresponding to the temperature of the cooling source at the top of the sealed casing creates an upward driving force, creating a mist flow that also pushes up the droplets. At this time, when a high voltage is applied between the inlet electrode 6 and the charging electrode 7 to give a charge to the droplet, the droplet rises while being resisted by the flow, and generates electricity during this rising process.
When the mist stream containing droplets reaches the collector electrode 8, the working fluid stream is unloaded by the collector electrode 8 and current flows to the load 9, so that:
The potential of the charging electrode 7 increases and the charged state continues. In this process, the energy for the working fluid to rise within the ascending flow path 1A is the thermal energy given to the working fluid by the heating device 2;
This thermal energy has been converted into a current to the load 9.

In addition, the pressure difference between the high temperature source and the low temperature source is balanced by the pressure difference due to the difference in liquid level between the ascending flow path and the descending flow path, so for example, if the pressure difference is 1 atmosphere, the difference in liquid level is about 6 for R-113 Freon.
It is m.

The unloaded working fluid then passes through a cooling device 10 where it is cooled and condensed back to liquid form. Therefore, the working fluid that has become a liquid falls down the downward flow path 1B under the action of gravity and is collected again at the lower part of the upward flow path 1A.

As described above, according to the present invention, EHD is achieved by utilizing low-level waste heat, etc., which was wasted in the past.
By heating and vaporizing the working fluid for power generation and turning the working fluid into a mist to form a mixed flow of droplets and gas, this mist flow is transported using the pressure difference caused by the temperature difference of waste heat. It is possible to lift the working fluid to the top against gravity, and the liquid is transported from the top to the bottom by the action of gravity, so natural circulation of the working fluid is completed without the need for a circulation device such as a pump. . Furthermore, droplets with a lower drift velocity due to the electric field have a larger electrical output, so by charging the droplets in the upward flow, it becomes possible to efficiently convert thermal energy into electrical energy. Therefore, a natural circulation type EHD power generation device with a simple structure is provided.

[Brief explanation of drawings]

The accompanying drawings are longitudinal sectional views of embodiments of the invention. 1: Sealed casing, 1A: Rising channel, 1B:
Downflow path, 2: heating device, 6: inlet electrode, 7: charged electrode, 8: collector electrode, 9: load, 10:
Cooling system.

Claims (1)

[Claims] 1. A sealed casing with a built-in fluid circulation channel including an ascending channel and a descending channel for low-temperature evaporated fluid such as fluorocarbons, and a heating device using waste heat that is provided at the bottom of the ascending channel and heats the fluid. a charging electrode and an inlet electrode provided directly above the heating device for charging the fluid; a collector electrode provided at the top of the upward flow path; and a collector electrode for charging the fluid after passing through the collector electrode. a cooling device provided near the top of the downflow passage for cooling; a natural circulation EHD power generation device;