KR20160147337A - Heat exchanger and exhaust heat recovery device using the same - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger and an exhaust heat recovery apparatus using the heat exchanger. More particularly, the present invention relates to a heat exchanger including a plurality of fins formed in a vertical direction and a plurality of inclined gas- And a heat exchanger for recovering exhaust heat of the exhaust gas through heat exchange and an exhaust heat recovery apparatus using the heat exchanger.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger and an exhaust heat recovery apparatus using the heat exchanger.

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat exchanger and an exhaust heat recovery apparatus using the heat exchanger. More particularly, the present invention relates to a heat exchanger and an exhaust heat recovery apparatus using the heat exchanger, The present invention relates to an exhaust heat recovery apparatus that recycles heat as a heat source for heat absorption and transfers heat by coupling a condenser to a heat exchanger and a heat exchanger that are smooth in discharge of condensed water.

A heat pump is a device that absorbs heat from a low-temperature heat source and produces high-temperature heat. It is a thermal conversion device that supplies more energy in the form of heat using less drive energy. COP (Coefficient of Performance) indicates the ratio of useful energy to required energy, and has a value of 3.0 or more in a normal operating condition, and serves as a radiator during the summer season and a radiator during the winter season. Heat pumps have become so important in the global air conditioning market due to their improved performance, stability and economy as they continue to develop.

In addition, since the heat pump is a non-combustion and environment-friendly device, it has been developed as a new hybrid boiler system integrated with a gas boiler. Exhaust gas generated from the boiler has been abandoned. Recently, exhaust heat recovered by using an exhaust heat recovery device By using the heat source as a heat source in the winter heat exchanger, it is possible to improve the efficiency of the heat pump and to carry out the non-phase cycle.

On the other hand, when heat is transferred from the exhaust gas, condensed water is generated on the outer surface of the fin formed in the heat exchanger during the heat exchange, and the generated condensed water reduces the fin efficiency of the heat exchanger, thereby deteriorating the performance of the exhaust heat recovery apparatus as a whole. Further, when the pins of the heat exchanger are installed in the horizontal direction, there arises a problem of discharge of condensed water.

FIG. 1 illustrates a conventional heat exchanger. Conventionally, a working fluid of a liquid is injected into a lower portion of a tube and a gas is discharged to an upper portion of the tube, so that the gas generated in the lower portion and the upper portion of the tube moves upward and is transferred to the condenser.

However, the method of injecting the working fluid of the liquid into the lower portion of the tube is not a problem when the injection amount of the working fluid of the liquid is sufficient. However, if the working fluid injection amount of the liquid is insufficient, There is a problem that the working fluid of the liquid is not filled and the heat transfer ability at the upper part of the tube is greatly deteriorated.

In addition, when the liquid state and the gaseous working fluid are mixed in the heat exchanger tube, the liquid working fluid capable of absorbing heat has a reduced contact area with the tube, thereby reducing the ability to absorb heat There is a problem.

In order to solve the above-mentioned problems, it is an object of the present invention to provide a heat exchanger capable of smooth discharge of condensed water and capable of separating a working fluid of a liquid and a working fluid of a gas in a tube.

Another object of the present invention is to provide an exhaust heat recovery apparatus having a heat transfer efficiency by combining a heat exchanger using a condenser heat exchanger and an evaporator.

According to an aspect of the present invention, there is provided an exhaust gas purifying apparatus comprising: a plurality of fins disposed in a pipe through which exhaust gas flows, A plurality of first fluid flow passages passing through the plurality of fins and arranged parallel to each other so that a first fluid for heat exchange with the exhaust gas flows therein; A plurality of bends coupled to an end of the first fluid flow path adjacent to each other of the plurality of first fluid flow paths to allow the first fluid to flow staggered along the plurality of first fluid flow paths; And

And a gas separation tube formed on the flow path of the first fluid and formed to be inclined upward in the direction of the first fluid flow for discharging the gas generated by heat exchange with the exhaust gas, A heat exchanger is provided.

Preferably, the first fluid flow path is provided in a direction perpendicular to the direction in which the exhaust gas flows, the plurality of fins being parallel to a direction in which the exhaust gas flows, and may be spaced apart in a direction perpendicular to the ground surface have.

Also, preferably, the first fluid may be introduced into the fluid flow path located at the top of the plurality of first fluid flow paths.

Also preferably, the gas separation pipe may be formed on the upper portion of the bent portion.

Further, preferably, the diameter of the gas separation pipe may be made smaller toward the lower side.

Also, preferably, the first fluid flow path may have a smaller cross sectional area toward the lower side.

Also preferably, the gas separation pipe may be formed on one end side or both end sides of the first fluid flow path.

Also, preferably, the plurality of gas separation pipes may be connected to one gas discharge pipe.

Further, it may further comprise a water storage tank provided below the plurality of pins to collect condensed water.

According to an aspect of the present invention, there is provided a heat exchanger comprising: a heat exchanger; And a first pipe is formed at one side of the heat exchanger and connected to an inlet of the first fluid flow path of the heat exchanger and a second pipe is formed at the other side of the heat exchanger to be connected to the plurality of gas separation pipes of the heat exchanger, And a second fluid flow path through which the two fluids flow, the condenser being configured to perform heat exchange between the first fluid and the second fluid, wherein the first fluid flows through the heat exchanger and the condenser, Device.

In the present invention, a plurality of pins are formed in a direction perpendicular to the paper surface to enable smooth discharge of condensed water generated in the exhaust gas, and a gas separation pipe inclined upward in the direction of the end of the fluid flow path is formed, By separating the fluid from the liquid working fluid within a short period of time, the amount of gas working fluid remaining in the fluid flow path is reduced to improve the heat transfer to the fluid flow path.

In addition, the present invention provides an effect of recovering and reusing the exhaust heat of the exhaust gas by forming the heat exchanger and the condenser so that heat can be exchanged by the condenser.

1 is a conventional heat exchanger.
2 is a front view showing an embodiment of a heat exchanger according to the present invention.
3 is a cross-sectional view showing a flow direction of the first fluid in the heat exchanger gas separation pipe according to the present invention.
4 is a front view showing a state where a water tank is installed in the heat exchanger according to the present invention.
5 is a front view showing another embodiment of the heat exchanger gas separation pipe according to the present invention.
6 is a front view showing another embodiment of the heat exchanger first fluid flow path and gas separation pipe according to the present invention.
7 is an operational state diagram showing an exhaust heat recovery apparatus according to an embodiment of the present invention.
8 is a circulation diagram of the exhaust heat recovery apparatus according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art to which the present invention pertains. The present invention may be embodied in many different forms and is not limited to the embodiments described herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and the same or similar components are denoted by the same reference numerals throughout the specification.

The heat exchanger 100 according to the present invention may include a plurality of fins 10, a first fluid flow path 20, and a gas separation pipe 30. 2 is a front view showing an embodiment of a heat exchanger according to the present invention.

A plurality of pins (10)

Referring to FIG. 2, one pin 10a may be formed of a thin plate-shaped member. The heat exchanger 100 is formed by spacing the fins 10a of the plurality of thin plate members side by side. The plurality of fins (10) can be formed in parallel to the direction in which the exhaust gas flows. The reason for arranging the exhaust gas in parallel with the flow direction of the exhaust gas is to allow hot air particles to pass between the fins 10a of the thin plate members arranged so as to be able to exchange heat between the air particles and the fins. If hot air passes through the fluid flow path 20 formed without the plurality of fins 10, only the outer surface of the fluid flow path 20 where heat exchange takes place. However, if it passes through the fluid flow path 20 in which the plurality of fins 10 are formed, heat exchange with the fin 10a of the plate member as well as the outer surface of the fluid flow path 20 can be performed. At this time, the hot air particles pass between the fins 10a and the fins 10a while simultaneously colliding with the fins 10a of the thin plate members having a relatively low temperature and performing heat exchange.

In addition, during the heat exchange between the exhaust gas and the fin 10a, condensed water is generated on the outer side of the fin 10a. The condensed water is water having relatively high specific heat, and by reducing the area of contact of the hot air particles with the fins 10a, it is possible to prevent heat exchange between exhaust gas and the fins 10a made of metal members. Accordingly, the condensed water reduces the efficiency of the fin 10a and deteriorates the performance of the exhaust heat recovery apparatus 200 as a whole, and therefore, a structure of the heat exchanger 100 for smooth discharge of condensed water is required.

In this case, if the fins 10a are stacked in a direction parallel to the paper surface, it is difficult to discharge the condensed water, so that the fins 10a can be arranged in a direction perpendicular to the paper surface and drained by gravity. In addition, in consideration of the surface tension of the water droplet, the interval between adjacent fins 10a can be formed so as to maintain a distance such that water droplets do not accumulate.

The plurality of fins 10 each formed of a thin plate-like member may be provided with a hole corresponding to the cross section of the first fluid flow path 20 so that the first fluid flow path 20 described later can pass therethrough, The size of the hole can be closely fitted to the first fluid flow path (20). And can be formed so as to be able to transfer heat from the respective fins 10a to the first fluid flow path 20 by close contact.

4 is a front view of a state in which a water tank is installed according to an embodiment of the present invention. If the condensed water generated in the process of exhaust gas and heat exchange flows into the boiler etc. through the pipe, it may cause the function of the boiler to be deteriorated or failure. 4, a water storage tank 12 capable of collecting condensed water generated at the lower ends of the plurality of fins 10 formed in a direction perpendicular to the paper surface can be formed. In the lower portion of the water storage tank 12, A drain valve 14 may be formed so as to discharge the exhaust gas.

The first fluid Flow path (20)

Referring again to FIG. 2, the first fluid flow path 20 may be formed in a jig remodeling or " d " shape. The first fluid flow path 20 may be formed by bending a single tube several times, but generally, the first fluid flow path 20 is formed by alternately horizontally and vertically stacking a plurality of straight tube- By connecting the bent U-shaped tubular bent portions 22 formed by the bending, it is possible to form the jigs or the " d " In addition, the formation of the first fluid flow path 20 in a jig shape or " d " shape allows the fluid flowing in the first fluid flow path 20 to stay in the first fluid flow path 20 for a longer time So that more heat can be exchanged.

The first fluid flow path 20 may be formed through a plurality of fins 10 in a direction perpendicular to the plane of the fin 10a. Accordingly, since the plurality of fins 10 are disposed in parallel to the direction in which the exhaust gas flows, the first fluid flow path 20 can be formed in a direction perpendicular to the direction in which the exhaust gas flows.

Referring to FIG. 1, as described above, in the related art, a working fluid of a liquid is injected into a lower portion of a fluid flow path, but a method of injecting a working fluid of a liquid into a lower portion of the tube is problematic However, if the working fluid injection amount of the liquid is not sufficient, the working fluid of the liquid is filled from the bottom, so that the working fluid of the liquid is not filled in the upper part of the tube. Therefore, as shown in FIG. 2, the working fluid is injected onto the first fluid flow path 20 so that the liquid flows from top to bottom.

In addition, it is preferable that the first fluid flow path 20 is formed as a tube having a circular section so as to be most suitable for heat exchange, and it is preferable that the thickness of the tube is thin, It can be formed by selecting an appropriate thickness to have a degree of rigidity.

In this case, the cross-sectional area of the first fluid flow path connected from the upper part to the lower part may be kept the same, or the cross-sectional area of the pipe connected from the upper part to the lower part may be made smaller as it goes down.

Sloping gas Separator (30)

2, a bent U-shaped bend 22 is connected to the end of the first fluid flow path 20, and the upper end of the bend 22, A gas separation pipe 30 formed so as to be inclined toward the gas separation pipe 30 can be formed.

Referring to FIG. 3, a part of the first fluid introduced into the liquid state through heat exchange is vaporized. In order to perform gas-liquid separation of the first fluid in the gaseous state and the first fluid in the liquid state, . In addition, the gas may be formed as a tube that is inclined upward in the upward direction by using a property that is lighter than liquid, and may have a diameter equal to or smaller than the diameter of the first fluid flow path 20.

At this time, it is preferable to form the gas separation pipe 30 in the bent portion 22 formed by bending, rather than forming the gas separation pipe 30 in the vertical direction at the middle point of the first fluid flow path 20. This is because the efficiency of gas-liquid separation can be improved by utilizing the property that the first fluid in the liquid state falls by the gravity in the bent bent portion 22 formed by bending.

The gas separator 30 may be formed so as to be inclined upward in the direction of the first fluid flow so that the first fluid may flow and smoothly separate the first fluid in a phase-change gas state without interference.

If the gas separation pipe is formed in the bent portion in a direction parallel to the flow direction of the first fluid in the liquid state, the efficiency of the gas-liquid separation may be changed according to the first fluid state in the first fluid flow path It is because. In addition, the amount of the first fluid in the liquid state and the amount of the first fluid in the gaseous state may be different depending on the position of the first fluid flow path 20, and the first fluid The gas separation pipe 30 may be formed on the upper portion of the bending portion 22 to prevent the exhaust gas from being discharged.

At this time, the reason why the first fluid in the gaseous state and the first fluid in the liquid state are separated is to increase the heat exchange efficiency. More specifically, when the first fluid in the liquid state and the gaseous state are mixed in the first fluid flow path 20 of the heat exchanger 100, the first fluid in the gaseous state already vaporized is mixed with the liquid This interferes with the heat absorption of the first fluid. And thus the contact area between the first fluid in the liquid state and the fluid flow path is reduced, resulting in a decrease in heat exchange efficiency.

Accordingly, by separating the first fluid that has changed into the gaseous state from the inside of the first fluid flow path 20 within a short period of time, the first fluid is formed to smoothly contact the inside of the first fluid flow path 20 with the first fluid in the liquid state. can do.

As shown in FIG. 2, a plurality of gas separation pipes 30 inclined upward with respect to the first fluid flow direction may be connected to one gas discharge pipe 32, and the gas discharge pipe 32, May be connected to one side of the condenser (40), and may be formed in the condenser (40) so that the first fluid and the second fluid can exchange heat.

5 is a front view showing a modification of the gas separation tube according to an embodiment of the present invention. As shown in FIG. 5, a plurality of gas separation pipes 30 inclined upward with respect to the first fluid flow direction may be formed only on one side of the ends of the first fluid flow path 20 in the form of a straight line. At this time, the reason for forming only one side portion is to facilitate the connection between the plurality of gas separation pipes 30, thereby facilitating fabrication of the gas discharge pipe 32.

Declining The cross-  Formed fluid Flow path  And gas Separator

In the heat exchanger according to the embodiment of the present invention, the first fluid in a liquid state flows into the upper portion of the heat exchanger, and all or most of the first fluid flows in the first fluid flow path (20) And may be formed to be in a gaseous state. The rate at which the first fluid in the inflowed liquid state is phase-changed can be varied by various factors. The temperature of the exhaust gas, the cross-sectional area of the first fluid flow path 20, the length, and the properties of the first fluid.

Therefore, it is necessary to design it in accordance with this, and a design is required to minimize or minimize the first fluid in the liquid state below the first fluid flow path 20. For this purpose, the temperature of the exhaust gas, The cross sectional area of the first fluid flow path 20 can be modified by a simple method without changing the cross sectional area of the first fluid flow path 20.

6 is a front view showing a modification of the first fluid flow path and the gas separation pipe according to another embodiment of the present invention. Referring to FIG. 6, it can be seen that the sectional areas of the first fluid flow path 20 and the gas separation pipe 30 can be made smaller toward the lower side.

The first fluid in the liquid state is injected into the upper part of the first fluid flow path 20 and the first fluid in the liquid state starts to vaporize gradually while the injected first fluid and the exhaust gas exchange heat. The amount of the first fluid in the liquid state flowing along the first fluid flow path 20 formed in the jig regeneration can be gradually reduced.

At this time, among the fluid flow paths stacked in the horizontal direction, the amount of the first fluid flowing in the first fluid flow path 20 formed on the upper side and the first fluid flow path 20 formed on the lower side is relatively And it may be inefficient in terms of heat exchange to use the first fluid flow path 20 having the same cross sectional area as many of the states even in a state where the amount of the first fluid in the liquid state is small.

Accordingly, it is possible to design the first fluid flow path 20 by reflecting the amount of the first fluid that is changed into the gas state while exchanging heat and discharged to the gas separation pipe 30, and the first fluid flow path 20 May be made smaller toward the lower side.

Also, as the amount of the first fluid in the liquid state decreases toward the lower side, the amount of the gaseous first fluid discharged through the gas separation pipe 30 due to heat exchange can also be reduced. Therefore, the gas separation pipe 30 can be formed to have a smaller cross sectional area as it goes downward by reflecting the design into the design of the gas separation pipe 30.

Exhaust heat recovery device using condenser

7 is an operational state diagram showing an exhaust heat recovery apparatus according to an embodiment of the present invention. The exhaust heat recovery apparatus 200 may include a heat exchanger 100 and a condenser 40 according to an embodiment of the present invention.

Referring to FIG. 7, thermal siphon principles may be used to effect heat exchange. Thermal siphons are sometimes referred to as thermosiphons. The thermal siphon principle is a device that moves heat without applying any extra energy by using the principle that heat flows from high to low. When there is a temperature difference between one side and the other side, cold air or heat of one side moves to the other side do. Therefore, in order to circulate the first fluid in the exhaust heat recovery apparatus 200 according to the present invention, a separate power device such as a pump may not be used.

In this case, the first fluid flow path inlet 20a formed at one side of the upper portion of the heat exchanger 100 can be connected to the first pipe 40a formed at one side of the condenser 40, and the gas discharge pipe 32 and the condenser 40 may be connected to the second pipe 40b.

In addition, a fluid inlet 42 through which the second fluid flows may be formed at one end of the condenser 40, and a fluid outlet 44 through which the second fluid may be discharged may be formed at the other end. The fluid inlet 42 may be formed in the direction in which the first tube 40a is formed and the fluid outlet 44 may be formed in the direction in which the second tube 40b is formed.

At this time, a second fluid flow path through which the second fluid can flow from the fluid injection port 42 toward the fluid discharge port 44 may be formed in the condenser 40. At this time, the first fluid and the second fluid circulate in opposite directions in the inside of the condenser 40, and mutually heat exchange is performed through the condenser 40. Accordingly, the second fluid in the liquid state flowing into the fluid injection port 42 receives heat from the first fluid in the gaseous state while passing through the condenser 40.

Accordingly, the first fluid can be formed to heat-exchange the heat exchanger 100 and the condenser 40 while continuously circulating the heat exchanger 100 and the condenser 40 without a separate power unit using the thermal siphon principle. In addition, the second fluid discharged from the fluid discharge port 44 is circulated to the evaporator of the heat pump by heat exchange in the condenser 40, thereby using the heat pump as a heat source of the heat pump, .

8 is a circulation diagram of the exhaust heat recovery apparatus according to an embodiment of the present invention. Referring to FIG. 8, it can be seen that the exhaust gas generated in the boiler flows into the flue, and the heat exchanger 100 is installed inside the rectangular duct or pipe through which the exhaust gas flows, and the first fluid and the second fluid It shows the process of circulation.

At this time, the inside of the rectangular duct through which the exhaust gas flows is formed at a high temperature, and the condenser 40 is formed outside the rectangular duct or the pipe, so that the exhaust heat of the exhaust gas having a high temperature can be recovered and recycled .

10: plural pins 10a: pin
12: Water tank 14: Drain valve
20: first fluid flow passage 20a: first fluid flow passage inlet
22: bent portion 30: gas separation pipe
32: gas exhaust pipe 40: condenser
40a: first pipe 40b: second pipe
40c: second fluid flow path 42: fluid injection port
44: fluid outlet 100: heat exchanger
200: exhaust heat recovery device

Claims (10)

A plurality of pins disposed in a pipe through which exhaust gas flows and spaced apart from each other by a predetermined distance;
A plurality of first fluid flow passages passing through the plurality of fins and arranged parallel to each other so that a first fluid for heat exchange with the exhaust gas flows therein;
A plurality of bends coupled to an end of the first fluid flow path adjacent to each other of the plurality of first fluid flow paths to allow the first fluid to flow staggered along the plurality of first fluid flow paths; And
And a gas separation tube formed on the flow path of the first fluid and formed to be inclined upward in the direction of the first fluid flow for discharging the gas generated by heat exchange with the exhaust gas, heat transmitter. The method according to claim 1,
The first fluid flow path is installed in a direction perpendicular to a direction in which the exhaust gas flows,
Wherein the plurality of fins are parallel to the direction in which the exhaust gas flows and are spaced apart in a direction perpendicular to the ground. 3. The method of claim 2,
Wherein the first fluid flows into a fluid flow path located at the top of the plurality of first fluid flow paths. The method of claim 3,
Wherein the gas separation pipe is formed at an upper portion of the bent portion. 5. The method of claim 4,
Wherein the diameter of the gas separation pipe is smaller toward the lower side. 5. The method of claim 4,
Wherein the first fluid flow path has a smaller cross sectional area toward the lower side. 5. The method of claim 4,
Wherein the gas separation pipe is formed on one end side or both end sides of the first fluid flow path. 5. The method of claim 4,
And the plurality of gas separation pipes are connected to one gas discharge pipe. 3. The method of claim 2,
Further comprising a water reservoir provided under the plurality of pins to collect condensed water. 10. A heat exchanger according to any one of claims 1 to 9, And
A first pipe is formed on one side of the heat exchanger and connected to an inlet of the first fluid flow path of the heat exchanger and a second pipe is formed on the other side of the heat exchanger to be connected to the plurality of gas separation pipes of the heat exchanger, And a condenser formed to have a second fluid flow path through which the fluid flows, so that the first fluid and the second fluid exchange heat,
Wherein the first fluid is formed to circulate the heat exchanger and the condenser.

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