JPH0246880B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a heat transfer promoting device for a condensing heat exchanger, and more particularly to a heat transfer device that removes condensate attached to a heat transfer surface using an electric field.

(Prior Art) Conventionally, a heat transfer promoting device 1 using an electric field as shown in FIG. 3 in a condensing heat exchanger is known.

The condensing heat exchanger (the entire figure is omitted) performs heat transfer by releasing latent heat of vapor of a heat medium such as water or fluorocarbon to a heat transfer surface 3 on the surface of a tube 2 through which cooling water flows.

However, the heat transfer surface 3 is damaged by the condensate.
A liquid film is formed that flows downward along the , and this liquid film inhibits the condensation of vapor. Therefore, the heat transfer accelerator 1 is configured to remove the condensate from the heat transfer surface 3.

A spiral wire electrode 4 is installed around the heat transfer surface 3 at a distance from the heat transfer surface 3. This wire electrode 4 is supported by a support 5. Then, the heat transfer surface 3 is used as the other electrode, and a high voltage is applied between the heat transfer surface 3 and the wire electrode 4. Then, as shown in FIG. 4, the condensate is drawn out from the heat transfer surface 3 toward the wire electrode 4. The condensate then flows along the line electrode 4 and is communicated with the waste liquid 6.

(Problems to be Solved by the Invention) Condensate is removed from the heat transfer surface 3 as described above. However, not all of the liquid film on the heat transfer surface 3 is removed; a thin liquid film remains, and the amount of heat transfer decreases accordingly.

An object of the present invention is to provide a heat transfer promoting device that can greatly improve the amount of heat transfer by promoting heat transfer at a portion of the heat transfer surface 3 where there is a thin liquid film.

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a cylindrical surface electrode provided at a distance from the heat transfer surface is added to the wire electrode, and the heat transfer surface and It is configured to apply a high voltage between it and the surface electrode.

(Function) When a high voltage is applied between the heat transfer surface and the cylindrical surface electrode, the condensed liquid on the heat transfer surface becomes droplet-like. Therefore,
The thickness of the liquid film on the heat transfer surface 3 other than the droplets becomes thinner, and the amount of heat transfer increases.

(Example) An example of the present invention will be described based on FIGS. 1 and 2. Components with the same reference numerals as in FIG. 3 indicate the same components.

Referring to FIG. 1, a cylindrical surface electrode 7 surrounds the heat transfer surface 3 and is fixed to a support 6. Heat transfer surface 3
A distance H is provided between the surface electrode 7 and the surface electrode 7.

In addition, a spacer 8 made of an insulator is provided on the support 5 so that the heat transfer surface 3 and the surface electrode 7 and the wire electrode 4 do not come into contact with each other.
is installed. This spacer 8 is in contact with the heat transfer surface 3 and maintains a distance H between the heat transfer surface 3, the surface electrode 7, and the line electrode 4.

A high voltage is applied between the wire electrode 4, the surface electrode 7, and the heat transfer surface 3. Then, as described above, the condensed liquid on the heat transfer surface 3 is first drawn out to the wire electrode 4 and removed. The thinned liquid film removed by the line electrode 4 above the surface electrode 7 is formed into droplets at the surface electrode 7, as shown in FIG. For this reason, heat transfer surface 3
The thickness of the liquid film becomes thinner in a portion 10 other than the location where droplets 9 are generated, and heat transfer is promoted.

It goes without saying that the present invention is not limited to the above embodiments. For example, the upper end or the lower end of the surface electrode 7 may be brought close to the line electrode 4 located above or below the surface electrode 7 and may be formed by tilting in a curved shape. Thereby, the area of the heat transfer surface 3 that becomes droplet-like can be made larger.

(Effects of the Invention) According to the present invention, condensation heat transfer can be greatly promoted by forming a thin liquid film into droplets.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an embodiment of the present invention, FIG. 2 is a partial sectional view showing the operation of the embodiment of FIG. 1, and FIG. 3 is a perspective view of a conventional heat transfer promoting device. FIG. 4 is a partial cross-sectional view showing the operation of the device of FIG. 3. 1: Heat transfer accelerator, 3: Heat transfer surface, 4: Line electrode, 7: Plane electrode.

Claims (1)

[Claims] 1. A wire electrode is installed at a distance from a heat transfer surface that releases latent heat of vapor of a heat medium, and the wire electrode is used as one electrode, and the heat transfer surface is used as the other electrode. In a heat transfer promotion device that applies a high voltage between the heat transfer surface and the wire electrode to draw condensate attached to the heat transfer surface from the heat transfer surface to the wire electrode and remove it, Heat transfer characterized by adding a provided cylindrical surface electrode to the wire electrode and applying a high voltage between the heat transfer surface and the surface electrode to turn the condensate attached to the heat transfer surface into droplets. Facilitator.