JPS5825936B2 - Onpuudanbouki - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention enables forced airflow generated by a fan or the like to
The present invention relates to a hot air heater that generates hot air by exchanging heat with water vapor and guides this hot air to a room to be heated for heating.

As shown in Figure 1, one of the systems that generates hot air that has been most commonly adopted recently among heating systems that utilize hot air is one that heats hot water heated by a heat source device 4A such as a burner. There is a type of hot water circulating circuit in which a hot air generating heat exchanger 3A for heating is installed in the middle of the two people.

In this case, the hot water circulation circuit 2A needs to be provided with an expansion tank T that is open to the atmosphere to alleviate expansion and contraction of the hot water.

In this tank, air easily enters the hot water, and the piping system and water storage tank are likely to be corroded by the circulation of the air contained in the hot water. If an attempt is made to circulate the hot water, the flow rate will be very slow and the film on the wall of the hot water flow path in the heat exchanger 3A will become thick.

In other words, the heat transfer coefficient is extremely low, resulting in poor heat exchange efficiency.

Another possibility is to use a pump or the like to forcefully circulate the hot water in order to keep the hot water reflux speed constant, but in this case, the disadvantage is that the equipment costs will increase due to the pump for refluxing the heat medium hot water. There is.

The cause of these problems lies in the use of hot water as a heat medium.

Therefore, a system has been developed that uses steam instead of hot water, and with this system, an expansion tank, a reflux pump, etc. can be omitted.

One of the water vapor type is described in the specification and drawings of Japanese Patent No. 20367.

The schematic structure thereof is shown in FIG. 4, and will be briefly described below.

21 is a water storage chamber in the steam generator 20, and 22 is a steam chamber.

A connecting pipe 23 extends directly from the upper end of the steam chamber 22,
A heat exchanger 24 is connected directly below the end thereof, and a lower end of the heat exchanger 24 is connected to the water storage chamber 21 by a communication pipe 25.

26 is a heat source device, 27 is fuel, and 28 is an air passage.

This has the following problems:

(a) Water vapor condenses in the heat exchanger 24 and descends as drain, but due to the volume reduction during the condensation, the heat exchanger 2
The inlet of 4 becomes negative pressure, and the water vapor chamber 2
Inhale water vapor from 2.

This water vapor intake relies exclusively on negative pressure suction, and the structure does not utilize the upward force of water vapor.

That is, this is because the communication pipe 23 connecting the inlet of the heat exchanger 24 and the steam chamber 22 is horizontal.

This is one of the reasons for lowering the heat exchange efficiency.

(0) The steam chamber 22 is of a normal pressure type and has low steam generation efficiency.

In addition, the heat radiation area of the steam chamber 1a including the upper communication pipe 23 is extremely large, resulting in large heat loss.

An object of the present invention is to solve the above-mentioned problems of the hot air heater having the structure illustrated in FIG.

The gist of the hot air heater of the present invention is as follows.

In order to facilitate understanding, the numbers used in the drawings related to the examples are appended.

A steam riser pipe 2a is connected to the upper end of the steam chamber 1a of the closed type decompression steam generator 1, and a drain descender extends from the upper end of the steam riser pipe 2a and is provided with a heat exchanger 3 in the middle. The pipe 2b is connected back to the steam generator 1, and the steam riser pipe 2a is covered with a heat insulating material 17, while the drain descender pipe 2b
is considered to be a bare tube.

This configuration has the following functions and effects.

(4) The steam in the steam chamber 1a is not only sucked in by the negative pressure caused by draining in the heat exchanger 3, but also rises through the riser pipe 2a due to its own volumetric expansion and natural upward force. It flows into 3 with force.

Such a fast flow of water vapor promotes evaporation from the water storage chamber 1b.

(Season) Since the steam generator 1 is under reduced pressure, its boiling point is low, which also contributes to promoting evaporation.

(Since the water vapor riser pipe 2a is covered with the heat insulating material 17, heat radiation when the water vapor rises through this pipe 2a is suppressed, and the water vapor flows into the heat exchanger 3 without losing the heat held during evaporation. To go.

) On the other hand, the drain downcomer pipe 2b is a bare pipe, and has a cooling effect due to contact with the outside air, which promotes the conversion of water vapor (still in a gaseous state) after heat exchange into a drain, and drains the water vapor (still in a gaseous state).
The goal is to create a negative pressure in the population and, by extension, increase the water vapor suction effect.

In this way, the flow rate (amount per unit time) of water vapor flowing into the heat exchanger 3 is large, and the amount of heat it holds is absolutely large, so there is a large temperature difference between it and the air sent from a fan etc. As a result, the heat exchange efficiency can be greatly improved compared to the conventional example shown in FIG.

Hereinafter, embodiments of the present invention will be described in detail based on FIG. 2.

1 may contain water a (a small amount of ethylene glycol, etc.) as a heating medium.

), and the pressure is reduced to below atmospheric pressure.This is a closed type steam generator which is made up of a lower water storage chamber 1b and a steam chamber 1a connected to the upper part.Water a is It is heated by a heat source device 4 such as a gas or oil burner or an electric heater.

Steam riser pipe 2 formed to lead upward from the steam chamber 1a
An inclined pipe 2c with fins for hot air generation and heat exchange is formed in communication from the upper end of a downwardly, and a vertical descending guide pipe is provided next to the inclined pipe 2c, so that the drain descending pipe 2b is connected to the inclined pipe 2c. The lower end port 2 b / of this drain descending pipe 2 b is opened and communicated with the inside of the closed pressure reduction type steam generator 1 .

A natural circulation circuit 2 for steam is formed by the steam chamber 1a, the rising pipe 2a, and the drain descending pipe 2b with the heat exchanger 3.

A heating air fan 10 is installed from the outside into the finned inclined pipe 2c of the drain descending pipe 2b in this water vapor natural circulation circuit l.
An air flow path 11 is formed through which the air is forcibly sent.

The entire steam chamber 1a and the steam riser pipe 2a are covered with insulation material 1.
Covered with 7.

On the other hand, the drain descending pipe 2b including the inclined pipe 2C is a bare pipe.

In the figure, 12 is a casing with a gear mechanism, and 13 is a hot air chamber for distributing and supplying generated hot air to a plurality of ducts 14.

Next, the heat exchange function in the hot air heater configured as described above will be explained.

The heat source device 4 heats and boils water a to generate steam.

This water vapor rises in the rising pipe 2a from the water vapor chamber 1a, and then reaches the heat exchanger 3 in the inclined pipe 2c, where the latent heat of the water vapor is transferred to the forced air flow via the fins, and the heat transfer causes the temperature to rise. Wind is generated and distributed to each duct 14 via the chamber 13 to provide the desired warm air heating.

In this case, the condensed condensate is returned to the water storage chamber 1b through the downcomer pipe 2b and reheated by efficiently dissipating the latent heat of vaporization of the water vapor into the air in the heat exchanger 3.

The volume of water vapor is drastically reduced by draining (approximately 1/1600).

A part of the water vapor flows down the drain downcomer pipe 2b to the water vapor chamber 1a while the temperature of the water vapor has decreased.

A partition wall 15 is provided at a position slightly distant from the lower end opening 2b' of the drain descending pipe 2b to open and communicate with the upper and lower intermediate positions of the space in the steam chamber 1a.

The partition wall 15 on the upper side and the lower side of this partition wall 15
The steam chambers 1a on both sides communicate with each other.

In other words, the returned water vapor immediately descends, touches the water surface, and condenses.

What is shown in FIG. 3 relates to another embodiment.

That is, instead of the partition wall 15, a partition wall 16 with an upper side closed and a lower side open is provided.

This has better condensation of the return water vapor than the partition wall 15 shown in FIG.

In any of the embodiments, the lower end port 2b' of the drain descending pipe 2b may be communicated with the water storage chamber 1b.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a hot air generator that is currently widely used, FIG. 2 is a schematic configuration diagram showing one embodiment of the present invention, and FIG. 3 is a schematic configuration diagram showing another embodiment of the present invention. , FIG. 4 is a schematic diagram showing a direct comparative example to the present invention. 1...Steam generator, 1a...Steam chamber, 2a...Steam riser pipe, 2b...
・Drain downcomer pipe, 3...Heat exchanger, 17...
...Insulation material.

Claims (1)

[Claims] 1. A steam riser pipe 2a is connected to the upper end of the steam chamber 1a of the closed type depressurized steam generator 1, and a heat exchanger is installed in the middle extending from the upper end of the steam riser pipe 2a. 3 is provided with a drain descending pipe 2b is connected back to the steam generator 1, and the steam rising pipe 2a is covered with a heat insulating material 17, while the drain descending pipe 2b is
is a hot air heater that is said to be a bare tube.