JPS58198688A - Heat exchanger - Google Patents

Abstract

PURPOSE:To obtain a heat exchanger small in size and prominent in efficiency by a method wherein mixing of two kinds of liquid, which are effecting heat exchange, is prevented while mutual heat transmission between them is promoted. CONSTITUTION:A heat exchanger 1, made by a triple pipes sturcture, is constituted so that the innermost pipe 3 and the outermost pipe 2 thereof are utilized as the flow paths of the liquids which are effecting the heat exchange, an intermediate pipe 4, provided with a gap 14 between the innermot pipe 3, is utilized as an enclosed path filled with a heat medium between the fluids flowing through said innermost pipe 3 and the outermost pipe 2, while this heat medium transmits the heat under accompanying with evaporating and condensing effects in the enclosed path. In accordance with such convection phenomenon of the fluid accompanying with the evaporating and condensing effects, the heat of the refrigerant is transmitted to water side with a high density and speed and an effect as a heat transmitting surface may be achieved along the whole area of the innermost pipe 3. This heat exchanger 1 functions as the condenser of a heat pump type hot-water supplying machine and is utilized to heat the water flowing through the innermost pipe 3 by the condensed refrigerant flowing through the outermost pipe 2 in order to produce the hot-water.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat exchanger that prevents fluids that exchange heat from mixing with each other, such as a heat exchanger between refrigerant and water in a water heater or cooler using a heat pump.

Conventionally, this type of heat exchanger has been constructed by having tubes through which each fluid flows flattened and placed side by side in contact with each other, or by constructing a coiled fluid flow pipe around the outer periphery of a cylindrical body that serves as one fluid passage. The one with a double-wrap and one-digit configuration, and the one with a triple-pipe configuration, allowing each fluid to flow through the innermost and outermost tubes, and providing leakage relief grooves in the 21E wall layer consisting of the innermost and intermediate tubes. A heat exchanger structure is adopted to prevent mixing of fluids.

In the conventional heat exchanger as described above, in any case, the heat transfer surfaces of the tubes that serve as the flow paths for the two fluids are provided by mechanical contact, so the entire circumference of the flow path tubes of the two fluids is connected. It could not be configured as an effective heat transfer surface. In addition, with regard to mechanically provided contact surfaces, it is difficult to make planar contact between curved surfaces made of pipes, and as a result, although there is a surface contact state overall, there is a line or line contact locally. Since it is in a point contact state and is not the best heat transfer surface,
It acted as a resistance to heat transfer. Therefore, conventionally configured heat exchangers have a structure that can prevent contamination between two fluids, but problems remain in terms of performance as a heat exchanger. This required a larger and more acidic component compared to the previous one.

The purpose of the present invention is to eliminate the following drawbacks of the conventional technology.It is an object of the present invention to prevent contamination between two fluids undergoing heat exchange, and also to improve the performance of the heat exchanger. By promoting Aikawa's heat transfer, the aim is to obtain a heat exchanger that is small and made of a small number of members.

In order to achieve the second object, the present invention provides a heat exchanger having a triple tube structure, in which the innermost tube and the outermost tube are used as a fluid flow path for exchanging heat, and the intermediate tube is connected to the innermost tube and the outermost tube. The pipe is a closed path filled with a heat medium between the fluid flowing through the pipe, and the heat medium conducts heat while evaporating and condensing in the closed path. With this configuration, the heat medium filled in the sealed passage receives heat from the heating side pipe wall and evaporates, and the heat is absorbed by the endothermic side pipe wall and condenses and liquefies, thereby reducing the heat medium itself. In a closed channel, a vigorous flow phenomenon occurs in which boiling vapor and liquid are mixed together.

In addition, in addition to the fact that the gas and liquid of the heating medium infiltrates into local gaps, heat exchange can be promoted over the entire area of the wall surface of the heat transfer tube. Fi'l' is submerged once, and the mixture of fluid in the innermost pipe or outermost pipe is detected by this pressure fluctuation, and if a leak occurs in the heat medium, an alarm or notification is made. It performs processing such as stopping operation.

Embodiments of the present invention will be described below with reference to the drawings. Fig. 1 is an overall configuration diagram when the heat exchanger of the present invention is used as a condenser of a heat pump water heater, Fig. 2 is a cross-sectional view showing a triple-pipe configuration, and Fig. 3 is a longitudinal sectional view. FIG. 4 is a cross-sectional view of the end portion of the heat exchanger of the present invention. In these figures,
Identical parts are indicated by the same numbers. 1 is a heat exchanger according to the present invention having a triple tube configuration, 2 is an outermost tube, 3 is an innermost tube, and 4 is an intermediate tube. In FIG. 1, a heat exchanger 1 of the present invention is shown.
This functions as a condenser for a heat pump water heater, and uses the condensed refrigerant flowing through the outermost tube 2 to heat water flowing through the innermost tube 3 to produce hot water. 6 is a compressor, 6 is an accumulator, 7 is an evaporator, 8 is a capillary tube,
9 is the j1-detecting device fist in the intermediate pipe 4, and detects an abnormal L-
The system detects fluctuations in IJ and stops the operation of the compressor 5. 1o is a hot water storage tank, 11 is a water circulation pump, 12 is a hot water supply pipe, 13 is a water supply pipe, and the heat exchanger 1 according to the present invention is attached to these.
In addition, it is configured as a heat pump water heater.

Second. 3. 4. In the detailed structure of the heat exchanger of the present invention shown in FIG. 1, the gap 14 formed between the innermost buttock 3 and the intermediate tube 40 is a closed path filled with a heat medium. Furthermore, 16 shown in FIG. 4 is the outermost connecting pipe, and 16 is #! Media filling sealed channel 14
This is a detection tube for detecting the internal pressure inside.

The features of the present invention in the above configuration are as follows:
In the heat exchanger 1 having a triple tube structure, the innermost tube 3 and the outermost tube 2 are used as fluid flow paths for exchanging heat, and the intermediate tube 4 is used as a 111
Note I: A gap ζ 114 is provided between the innermost tube 3 and the fluid flowing through the innermost tube 3 and the outermost tube 2 as a closed path filled with heat medium, and the heat medium is evaporated and condensed in the closed path. The key point is that the heat is transmitted while accompanied by heat. In other words, the outermost tube 2
The heat medium in the closed path heated by the high-temperature refrigerant gas from the compressor 5 that has flowed into the chamber is boiled and evaporated to form the gap 14 and the innermost pipe 3.
In the local gap at the contact surface with the water, an intense flow convection phenomenon of gas-liquid mixing occurs, and heat is transferred to the water side flowing through the innermost tube 3, absorbing heat t' and condensing a. Due to the flow convection phenomenon accompanied by the evaporation and condensation effect of the heat medium, the heat of the refrigerant is transmitted to the water pipe at high speed due to its high density, and by making the entire area of the innermost pipe 3 act as a heat transfer surface, the heat is transferred. This promotes exchange and greatly improves the performance of the heat exchanger.

In addition, the internal pressure of the heat medium filled sealed passage is detected by the detection device 9 using the detection tube 16, so if the fluid in the innermost tube 3 or the outermost tube 2 gets mixed in due to fluctuations in the internal pressure, This prevents the refrigerant and the lubricating oil in the refrigerant from mixing with water by stopping the operation of the device.

As described above, the heat exchanger of the present invention is a heat exchanger having a three-tube configuration, in which the innermost tube and the outermost tube are used as the fluid flow path for exchanging heat, and the intermediate tube is the innermost tube described in II. The outermost tube is a closed path filled with heat medium between the flowing fluid, and the heat medium evaporates and condenses in the closed path? Since the heat medium is made to dissipate heat while not acting f′1′, the heat medium flows over the entire flow path of the two fluids and acts as a heat transfer surface. Second, it can greatly improve the performance of the heat exchanger because it rapidly transfers heat through intense convection, and therefore requires smaller size and a smaller amount of parts compared to the amount of heat exchanged. A heat exchanger can be constructed with

In addition, the internal pressure of the heat medium is also used as a medium for detecting leakage of fluid in the innermost pipe and outermost pipe, so by detecting fluctuations in the internal pressure, it is possible to prevent fluid from getting mixed in during heat exchange. It has the effect of preventing

Furthermore, when a heat pump is configured using the heat exchanger of the present invention as a condenser or evaporator, the heat exchange performance is excellent, and the load on the compressor is reduced, resulting in economical operation with a high coefficient of performance. It has a 1-1 band effect, such as being able to perform the following steps.

[Brief explanation of the drawing]

Fig. 1 is an overall configuration diagram when the heat exchanger of the present invention is used as a condenser of a heat pump water heater, Fig. 2 is a cross-sectional view of a triple pipe configuration, Fig. 3 is a vertical sectional view, and Fig. 4 is a sectional view of the end configuration. 1...Heat exchanger, 2...Outermost tube, 3...
...Innermost pipe, 4...Middle pipe, 9...
Internal pressure detection device, 14... Heat medium filling sealed path gap,
16...Detection tube.

Claims (2)

[Claims] (1) The innermost tube and the outermost tube of the triple tube structure are used as a fluid flow path for exchanging heat, and the intermediate tube is used as a heat medium-filled sealed path between the fluid flowing through the innermost tube and the outermost tube, and The heat exchanger transmits heat while the heat medium undergoes evaporation and condensation in a closed path. (2) The heat exchanger according to claim 1, which is provided with an internal pressure detection device for the closed passage filled with a heating medium, and detects contamination of fluid in the innermost pipe or the outermost pipe line based on fluctuations in pressure.