JP2005024132A - Evaporator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an evaporator capable of satisfactorily performing evaporation and securely enabling a reduction in size. <P>SOLUTION: In this evaporator 10 for a thermoelectric generating device, an evaporation part 12 is is formed of the opposed faces 14A of plate-like parts 14, spaces between the opposed faces 14A are allowed to communicate with each other along the flow direction of a hot medium, and a critical heat flow flux rising means is formed by the opposed faces 14A themselves. Accordingly, in the spaces of the evaporation part 12, the bypassing of a liquid (condensed heat medium) from the downstream side can be produced in a specified portion, and the critical heat flow flux in the evaporation part 12 can be increased. By this, even if the evaporation part 12 is heated to a high temperature, film boiling is hard to be produced, and the condensed heat medium can be satisfactorily evaporated by nucleate boiling. As a result, since the evaporation of the condensed heat medium can be performed without any problem even if the evaporation part 12 is reduced in size to such a degree that is easily heated to a high temperature, the evaporation part 12 can be reduced in size accordingly to promote a reduction in size of the entire evaporator. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an evaporator that generates a vapor of the liquid by heating the liquid with a high-temperature medium.
[0002]
[Background]
In recent years, for example, a liquid vapor such as a fluorine-based inert liquid is generated by exhaust gas exhausted from an engine, the condensation surface of the thermoelectric module is heated by this vapor, and the cooling surface is cooled by cooling water. Thermosiphon type thermoelectric generators that generate electricity based on the temperature difference between the condensation surface and the cooling surface of a thermoelectric module have been developed.
[0003]
Such a thermoelectric generator is provided with an evaporator that evaporates a condensed heat medium using a duct through which exhaust gas flows (for example, Patent Document 1). Specifically, the structure of the evaporator is such that the duct is provided so that the exhaust gas flows in a substantially horizontal direction, and in this duct, the evaporating portion is oriented in a direction (vertical direction) perpendicular to the horizontal flow of the exhaust gas. The heat transfer tube becomes through. And since the duct is immersed in the stored condensed heat medium, the heat transfer tube is heated by the exhaust gas from the outer peripheral side, and the liquid entering the heat transfer tube is evaporated by this heating.
[0004]
According to Patent Literature 1, the evaporator is miniaturized by adopting the following configuration. That is, in the evaporator, the temperature distribution along the flow direction of the exhaust gas is higher on the upstream side and lower toward the downstream side, but the critical heat flux has the same diameter regardless of the temperature part distribution. If the heat transfer tubes are arranged uniformly from the upstream side to the downstream side, the heat transfer tubes on the downstream side have an excessively large critical heat flux with respect to the exhaust gas at a low temperature, resulting in excessive performance as the heat transfer tubes to be used. Accordingly, in Patent Document 1, focusing on this point, a downstream heat transfer tube having a smaller limit heat flux, that is, having a smaller diameter, is used to maintain a sufficient limit heat flux while maintaining a small size. Is realized.
[0005]
[Patent Document 1]
JP2003-156201A
[0006]
[Problems to be solved by the invention]
By the way, in order to promote further downsizing of the evaporator, it is necessary to further reduce the diameter of the heat transfer tube. A situation occurs that easily exceeds the bundle. In such a situation, the heat transfer tube is extremely heated, and the nucleate boiling of the liquid is prevented inside the heat transfer tube and instead film boiling occurs, so that the liquid does not easily evaporate and the evaporation efficiency decreases. .
[0007]
An object of the present invention is to provide an evaporator that can perform evaporation well and can be reliably reduced in size.
[0008]
[Means for solving the problems and effects]
An evaporator according to claim 1 of the present invention includes a flow path section for flowing a high temperature medium, and an evaporation section for heating a liquid with the high temperature medium flowing through the flow path section to generate vapor of the liquid. The section is provided with a limit heat flux raising means for raising the limit heat flux of the evaporation section.
According to the present invention, since the limiting heat flux increasing means is provided in the evaporation section, film boiling is less likely to occur even when the evaporation section becomes higher in temperature, and liquid evaporation is performed well by nucleate boiling. Become. In addition, since the liquid can be evaporated without hindrance even if the evaporator is made small enough to be hotter, the miniaturization of the evaporator facilitates the miniaturization of the entire evaporator.
[0009]
An evaporator according to a second aspect of the present invention is the evaporator according to the first aspect, wherein the critical heat flux increasing means is a surface in contact with the liquid that has entered the evaporation section, and has an uneven surface. It is formed by.
Here, the concavo-convex shape is formed by processing a fine rough surface by machining or the like, pasting a metal crystal on the surface, or providing a fine fin (low fin) on the surface.
According to the present invention, the capillarity due to the uneven portion of the surface causes the liquid to enter the evaporation portion and the critical heat flux is increased, so that film boiling is less likely to occur and the size is reduced. Is surely promoted.
[0010]
According to a third aspect of the present invention, there is provided the evaporator according to the first or second aspect, wherein the evaporation section is arranged in parallel in a direction orthogonal to the flow direction of the high temperature medium. A pair of plate-like portions are provided, and the liquid is configured to enter between these plate-like portions, and the critical heat flux increasing means is formed by facing surfaces of the plate-like portions facing each other. It is characterized by that.
According to the present invention as described above, the opposed surfaces of the plate-like portions constituting the evaporation portion communicate with each other from the upstream to the downstream along the flow direction of the high-temperature medium, so that a conventional heat transfer tube having a closed cross section is used. In comparison with the case, the liquid flows from the downstream side to the predetermined part of the evaporation section, the critical heat flux is increased, and the miniaturization of the evaporator is further promoted.
[0011]
The evaporator according to claim 4 of the present invention is the evaporator according to claim 3, wherein a part of the facing surface is provided with a bulging part bulging to the flow path part side. It is characterized by.
According to the present invention as described above, by providing the bulging portion, the liquid more easily flows from the upstream side and the downstream side toward the bulging portion, and the critical heat flux is more reliably increased, Further downsizing can be realized.
In addition, the high-temperature medium flowing through the flow path section produces a vortex on the downstream side that has passed through the bulging section, and exerts a peeling effect, and the high-temperature medium self-vibrates, thereby heat transfer efficiency from the high-temperature medium to the evaporation section This improves the efficiency of evaporation.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, each embodiment of the present invention will be described with reference to the drawings. In the second and later embodiments described later, the same members and the same functional members as the components described in the first embodiment will be denoted by the same reference numerals, and descriptions thereof in the second and subsequent embodiments will be omitted or omitted. Simplify.
[0013]
[First Embodiment]
FIG. 1 is a side cross-sectional view showing an overall outline of a thermoelectric generator 1 to which an evaporator 10 according to the present embodiment is applied. FIG. 2 is a perspective view schematically showing the evaporator 10 of the thermoelectric generator 1. 3A is a cross-sectional plan view of the evaporator 10, and FIG. 3B is a side cross-sectional view thereof (cross-sectional view taken along the line BB in FIG. 3A). FIG. 4 is a plan sectional view showing the thermoelectric conversion unit 20 of the thermoelectric generator 1.
[0014]
In FIG. 1, a thermoelectric generator 1 circulates an exhaust gas or the like discharged from an internal combustion engine such as an engine as a high-temperature medium (see a black arrow) through an evaporator 10 and heats it. It is a device that generates steam of a condensed heat medium (liquid) such as an inert liquid and supplies it to the upper thermoelectric conversion unit 20, and converts the heat energy of the vapor into electric energy in the thermoelectric conversion unit 20 to generate electricity. In general, the evaporator 10 and the thermoelectric converter 20 are covered with a housing 30.
[0015]
The evaporator 10 penetrates the condensing heat medium storage portion 31 provided below the housing 30 in the horizontal direction, is immersed in the condensing medium up to a position near the upper surface, and FIGS. As also shown in A) and (B), a plurality of flow path portions 11 through which the high-temperature medium passes and a plurality of evaporation portions 12 into which the condensed heat medium in the storage portion 31 enters from below are alternately provided in the width direction. ing.
[0016]
Each flow path portion 11 includes an inlet portion 11A and an outlet portion 11B that are opened in a vertically long rectangular shape. A plurality of fins 13 that also serve as reinforcements are provided in the interior of the flow path portion 11 with an interval in the vertical direction. These fins 13 are continuously provided from the inlet portion 11A to the outlet portion 11B, and the heat transfer efficiency is improved by increasing the effective heat transfer area.
[0017]
Each evaporating unit 12 includes an inlet portion 12A and an outlet portion 12B that are opened up and down, and these inlet / outlet portions 12A and 12B have a horizontally long rectangular shape. Thereby, the inside of the evaporation part 12 is made into the space which continued from the upstream to the downstream along the flow direction of the high-temperature medium, and this space is connected up and down.
[0018]
The partition wall part that separates the flow path part 11 and the evaporation part 12 and the partition wall part that separates the evaporation part 12 on both sides in the width direction and the outside are arranged in a direction perpendicular to the flow direction of the high-temperature medium (the same in the width direction). The metal plate-like portion 14 is provided, which is also continuous along the flow direction of the high-temperature medium and is also continuous in the vertical direction. Then, the condensed heat medium that has entered from the inlet portion 12A below the evaporator 12 is heated by the plate-like portion 14 that is transferred from the high-temperature medium into steam, and is supplied from the upper outlet portion 12B to the thermoelectric converter 20 side. Is done.
[0019]
Here, the limit heat flux raising means according to the present invention is formed by a pair of flat opposing surfaces 14A of each plate-like portion 14 forming the evaporation portion 12. That is, since the space formed between the opposed surfaces 14A is continuous in the flow direction of the high-temperature medium, the condensed heat medium on the downstream side circulates upstream in the space when the condensed heat medium evaporates. Thus, the condensing heat medium on the downstream side that wraps around raises the critical heat flux of the evaporation section 12.
[0020]
In addition, in the present embodiment, the surface of the facing surface 14A is processed into a concavo-convex shape, and another limiting heat flux increasing means according to the present invention is also formed by the facing surface 14A processed into the concavo-convex shape. At this time, the uneven shape is such that the surface is finely roughened by machining or the like, the metal crystal is attached to the surface, or fine fins (low fins) are continuously provided on the surface. Formed with. Then, the capillary phenomenon caused by the concavo-convex facing surface 14 </ b> A promotes the sucking supply of the condensed heat medium from the storage unit 31 into the evaporation unit 12, and this increases the critical heat flux of the evaporation unit 12.
[0021]
The above is the configuration of the evaporator 10. In such an evaporator 10, the amount of evaporation on the upstream side is large in the flow direction of the high-temperature medium as in the conventional case, and the amount of evaporation decreases toward the downstream (FIG. 2). (See the white arrow inside.)
[0022]
On the other hand, in FIG. 4, the thermoelectric conversion part 20 is provided with the several electric power generation plate 21 arranged in parallel along the flow direction of a high temperature medium. The power generation plate 21 has a configuration in which a plurality of thermoelectric modules 23 are arranged on both front and back surfaces of a hollow plate-like cooling plate 22, and cooling water is supplied into the cooling plate 22 from a cooling water circulation means (not shown) to cool the thermoelectric module 23. The surface 23A is cooled. In contrast, the surface of the thermoelectric module 23 is a condensing surface 23B, and the vapor from the evaporator 10 heats the condensing surface 23B and condenses on the condensing surface 23B. Then, electric power is generated by the thermoelectric module 23 according to the temperature difference between the cooling surface 23A and the condensing surface 23B.
[0023]
These power generation plates 21 are suspended so that the condensation surface 23B of the thermoelectric module 23 is perpendicular to the flow direction of the high-temperature medium, and the pitch of each power generation plate 21 in the flow direction is small on the upstream side, It becomes larger as it goes downstream. That is, they are densely arranged on the upstream side and are arranged so as to become rough toward the downstream side. As a result, a large amount of steam generated upstream can be received by the larger condensing surface 23B, and a small amount of steam generated downstream can be received by the smaller condensing surface 23B. The amount of condensation on the condensing surface 23B toward the downstream also has substantially the same distribution as the amount of evaporation.
[0024]
Then, the condensed heat medium condensed on the condensing surface 23B falls back to the storage unit 31 and is heated again by the evaporator 10 to evaporate, and this evaporation and condensation are repeated.
By the way, a communication hole 32 is provided in the upper center of the housing 30 to allow the thermoelectric converter 20 (inside the housing 30) to communicate with the outside. The communication hole 32 has a role of maintaining the inside of the housing 30 at a substantially atmospheric pressure, and when the operation of the thermoelectric generator 1 is started, air in the housing 30 is driven upward by steam from the evaporator 10. Then, the air is exhausted from the communication hole 32 to the outside.
[0025]
Although not shown, the communication hole 32 is provided with a filter or the like that allows air to pass but does not allow steam to pass through, so that the steam is not discharged. Further, when it is desired to maintain the interior of the housing 30 at a predetermined pressure that is not atmospheric pressure, a pressure adjustment valve or the like may be provided in the communication hole 32.
[0026]
According to this embodiment, there are the following effects.
That is, in the evaporator 10 of the thermoelectric generator 1, the evaporation part 12 is formed by the opposing surface 14A of the plate-like part 14, and the space between the opposing surfaces 14A communicates along the flow direction of the high-temperature medium. Since the limiting heat flux increasing means is formed at 14A, unlike the conventional heat transfer tube having a closed cross section, in the space of the evaporation section 12, the condensing heat medium wraps around the predetermined portion from the downstream side. The critical heat flux of the evaporation part 12 can be increased. This makes it difficult for film boiling to occur even when the temperature of the evaporating unit 12 becomes higher, and the condensed heat medium can be evaporated well by nucleate boiling. Therefore, even if the evaporation section 12 is made small enough to easily reach a higher temperature, the condensed heat medium can be evaporated without hindrance, and the evaporation section 12 can be downsized to facilitate the downsizing of the entire evaporator.
[0027]
Further, the surface of the facing surface 14A has an uneven shape, and the limiting heat flux raising means is also formed by this uneven portion, so that the condensed heat medium is evaporated to the evaporation portion 12 by the capillary phenomenon due to the uneven portion of the surface. Is actively performed, the limit heat flux can be further increased, film boiling is less likely to occur, and downsizing can be promoted more reliably.
[0028]
Since the facing surface 14A is formed on the plate-like portion 14, an uneven portion is easily formed on the surface of the sheet metal before assembly of the evaporator 10 by, for example, bending or brazing of the sheet metal. it can. For this reason, productivity of the evaporator 10 can be improved and production cost can also be reduced.
[0029]
[Second Embodiment]
FIGS. 5A and 5B show a plan sectional view and a side sectional view (a sectional view taken along line BB in FIG. 5A) of the evaporator 10 according to the second embodiment of the present invention.
In the present embodiment, the shape of the fins 13 provided in the flow path portion 11 is greatly different from that of the first embodiment. Other configurations, such as the surface processing on the facing surface 14A, are substantially the same as the evaporator 10 of the first embodiment.
[0030]
The fins 13 in the present embodiment have a shape divided into a plurality of stages (in this embodiment, five stages) along the flow direction of the high-temperature medium, and are arranged in a staggered manner between the stages. The length of the fin 13 in each step is the same. In addition, a slight gap (see (A)) is formed between the steps, but the size of the gap is arbitrary, and there may be no gap. Further, an overlap portion by the fins 13 may be provided at the front and rear stages, for example, by the rear fins 13 entering between the front fins 13.
[0031]
According to the fin 13, as shown in FIG. 5C, the high-temperature medium passing between the pair of fins 13 in the previous stage is deprived of heat at the portion in contact with the pair of fins 13, and the temperature is somewhat lowered. However, on the fin 13 side in the rear stage, the high-temperature medium whose temperature has decreased (see the white arrow) does not come into contact with the fin 13 on the rear stage side, and the high-temperature medium near the center with a small temperature drop in the front stage ( A black arrow) touches the fin 13 on the rear stage side. For this reason, the heat flux at the fins 13 at the rear stage is substantially the same as the heat flux at the fins 13 at the front stage (actually slightly smaller), and the amount of evaporation at the portion corresponding to each stage in the evaporator 12 is uniform. Is achieved. That is, in the evaporation unit 12, the distribution of the evaporation amount of the condensed heat medium along the flow direction of the high-temperature medium becomes substantially constant from upstream to downstream.
[0032]
In the above-described embodiment, the fins 13 are divided into a plurality of stages along the flow direction of the high-temperature medium and are arranged in a staggered manner, whereby the distribution of the evaporation amount of the condensed heat medium is substantially reduced along the flow direction of the high-temperature medium. Although it is possible to make the same, the illustration is omitted, but in order to make the distribution of the condensation amount on the condensation surface 23B of the thermoelectric converter 20 the same as the distribution of the evaporation amount, the arrangement pitch of each power generation plate 21 is increased from upstream to downstream. It is sufficient to make them the same, and the design can be simplified.
[0033]
[Third Embodiment]
FIGS. 6A and 6B show a plan sectional view and a side sectional view (a sectional view taken along line BB in FIG. 6A) of the evaporator 10 according to the third embodiment of the present invention.
Also in this embodiment, the shape of the fin 13 provided in the flow path part 11 is greatly different from the first and second embodiments. Other configurations are substantially the same as those of the evaporator 10 of the first and second embodiments.
[0034]
The fins 13 in the present embodiment are divided into a plurality of stages (six stages in the present embodiment) along the flow direction of the high-temperature medium, and are arranged in a staggered manner as in the second embodiment. However, in the present embodiment, the first-stage fin 13A has the longest length, the second and third-stage fins 13B have the longest length, and the fourth to sixth-stage fins 13C have the longest length. short. The shorter the fins 13, the better the heat transfer performance per unit area.
[0035]
Therefore, according to the present embodiment, the heat transfer performance of each stage is improved toward the downstream side. Therefore, in the evaporation unit 12, the evaporation amount can be reliably increased toward the downstream side, compared with the second embodiment. Thus, the distribution of the evaporation amount from the upstream to the downstream can be made more uniform. In addition, by reducing the length of the fins 13C and the like, the size of the evaporator 10 in the flow direction can be reduced in order to obtain the same evaporation amount as a whole, and the evaporator itself can be downsized.
[0036]
Further, by arranging the fins 13A most coarsely and densely in the order of the fins 13B and 13C, the heat transfer area of the entire fin 13C is the largest, and then the heat transfer area of the entire fin 13B is large. The heat transfer area is the smallest.
Further, the fins 13A are arranged most coarsely, and are arranged densely in the order of the fins 13B and 13C. In terms of heat transfer area, the heat transfer area of the entire fin 13C is the largest, the heat transfer area of the entire fin 13B is then large, and the heat transfer area of the fin 13A is the smallest.
[0037]
Therefore, according to the present embodiment, the heat transfer area of each stage increases toward the downstream side. Therefore, in the evaporation unit 12, the amount of evaporation can be reliably increased toward the downstream side, compared to the second embodiment. Thus, the distribution of the evaporation amount from the upstream to the downstream can be made more uniform.
Furthermore, by reducing the length of the fins 13C and the like, the size in the flow direction of the evaporator 10 can be reduced in order to obtain the same evaporation amount as a whole, and further miniaturization can be realized.
[0038]
[Fourth Embodiment]
FIGS. 7A and 7B show a plan sectional view and a side sectional view (a sectional view taken along line BB in FIG. 7A) of the evaporator 10 according to the fourth embodiment of the present invention.
In the present embodiment, the shape of the internal space of the evaporation section 12 (flow path section 11) is significantly different from that in the third embodiment. Other configurations are substantially the same as those of the evaporator 10 of the third embodiment.
[0039]
That is, the internal space of the evaporation unit 12 of the present embodiment is wide on the upstream side and narrows toward the downstream. Further, in the flow path portion 11, the width is narrowed on the upstream side and becomes wider toward the downstream side. For this reason, the difference in heat transfer area between the stages provided with the fins 13A, 13B, and 13C can be made larger than the difference in heat transfer area in the third embodiment, and the heat flux on the downstream side can be further increased. Thus, the evaporation amount can be increased, and the evaporation amount distribution can be made more uniform.
[0040]
Furthermore, in this embodiment, since the evaporation part 12 is expanded toward the upstream side, the critical heat flux of the evaporation part 12 on the upstream side can be increased. Thereby, in the evaporation part 12, the dimension of the flow direction of a high temperature medium can be shortened, and the evaporator 10 can be further reduced in size.
[0041]
[Fifth Embodiment]
FIGS. 8A and 8B are a plan sectional view and a side sectional view (a sectional view taken along line BB in FIG. 8A) of the evaporator 10 according to the fifth embodiment of the present invention.
According to the present embodiment, a part of the facing surface 14A of the evaporation part 12 is provided with the semicircular bulging part 14B that bulges toward the flow path part 11 side. It is very different from the form. Other configurations are substantially the same as those of the evaporator 10 of the third embodiment.
[0042]
The bulging portion 14B corresponds to the boundary portion of each stage of the fin 13 and is provided continuously in the vertical direction (same as the rising direction of the steam). According to such a configuration, as shown in FIG. 8C, the high-temperature medium that has passed through the bulging portion 14B collides with the facing surface 14C (the surface on the opposite side of the facing surface 14A) on the flow path portion 11 side. Thus, a peeling effect is produced, and self-excited vibration is generated in the high temperature medium, so that the heat transfer efficiency on the high temperature medium side can be improved, and the condensed heat medium can be efficiently evaporated.
[0043]
Further, by providing the bulging portion 14B, the evaporation portion 12 side induces the wraparound portion 14B to circulate into the bulging portion 14B from the upstream side and the downstream side of the bulging portion 14B. Since it also serves as a storage part for supplying the condensed heat medium to the upper and downstream gaps, the configuration is different from that of the fourth embodiment, but the limit heat flux of the evaporation part 12 can also be increased, and the evaporation part 12 and therefore Further downsizing of the evaporator 10 can be realized.
[0044]
Note that the present invention is not limited to the above-described embodiments, and includes other configurations that can achieve the object of the present invention, and includes the following modifications and the like.
For example, in each of the above embodiments, the evaporation part 12 is formed by the plate-like part 14, but the evaporation part according to the present invention may be formed by using a conventional heat transfer tube. However, in this case, it is necessary to provide a critical heat flux increasing means by surface processing or the like on the inner surface of the heat transfer tube to satisfy the constituent requirements of claim 2 of the present invention.
And when the evaporation part 12 is formed by the plate-shaped part 14, it is not necessary to form the surface in uneven | corrugated form, and even in such a case, it is included in invention of Claim 3 etc. of this invention.
[0045]
In the above embodiment, the example of the evaporator 10 in which the evaporator of the present invention is applied to the thermoelectric generator 1 has been described. However, the evaporator of the present invention is not limited to this and may be applied to a boiler system or the like. The use of the evaporator is arbitrary.
[0046]
In addition, the best configuration, method and the like for carrying out the present invention have been disclosed in the above description, but the present invention is not limited to this. That is, the invention has been illustrated and described primarily with respect to particular embodiments, but may be configured for the above-described embodiments without departing from the scope and spirit of the invention. Various modifications can be made by those skilled in the art in terms of quantity, other details, and the like.
Therefore, the description limited to the shape, quantity and the like disclosed above is an example for easy understanding of the present invention, and does not limit the present invention. The description by the name of the member which remove | excluded the limitation of one part or all of such restrictions is included in this invention.
[Brief description of the drawings]
FIG. 1 is a side sectional view showing a schematic overall configuration of a thermoelectric power generator to which an evaporator according to a first embodiment of the present invention is applied.
FIG. 2 is a perspective view schematically showing an evaporator.
3A is a plan sectional view of an evaporator, and FIG. 3B is a side sectional view thereof (sectional view taken along line BB in FIG. 3A).
FIG. 4 is a plan sectional view showing a thermoelectric conversion part of a thermoelectric generator.
5A is a plan sectional view of an evaporator according to a second embodiment of the present invention, FIG. 5B is a side sectional view thereof (sectional view taken along line BB in FIG. 5A), and FIG. 5C is necessary. FIG.
6A is a plan sectional view of an evaporator according to a third embodiment of the present invention, and FIG. 6B is a side sectional view thereof (sectional view taken along line BB in FIG. 6A).
7A is a plan sectional view of an evaporator according to a fourth embodiment of the present invention, and FIG. 7B is a side sectional view thereof (sectional view taken along line BB in FIG. 7A).
8A is a plan sectional view of an evaporator according to a fifth embodiment of the present invention, FIG. 8B is a side sectional view thereof (sectional view taken along line BB in FIG. 8A), and FIG. 8C is necessary. FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 ... Evaporator, 11 ... Channel part, 12 ... Evaporating part, 14 ... Plate-shaped part, 14A ... Opposite surface, 14B ... Swelling part.

Claims (4)

In the evaporator (10)
A flow path section (11) for flowing a high-temperature medium;
An evaporation section (12) for heating the liquid with the high-temperature medium flowing through the flow path section (11) to generate vapor of the liquid,
The evaporator (10) characterized in that the evaporator (12) is provided with a limit heat flux raising means for increasing the limit heat flux of the evaporator. The evaporator (10) according to claim 1,
The limit heat flux increasing means is an evaporator (12A), which is a surface (14A) that comes into contact with the liquid that has entered the evaporation section (12), and has an uneven surface (14A). 10). In the evaporator (10) according to claim 1 or 2,
The evaporation section (12) includes at least a pair of plate-like portions (14) arranged in parallel to a direction orthogonal to the flow direction of the high-temperature medium, and between these plate-like portions (14). An evaporation part (12) into which the liquid enters is configured,
The evaporator (10), wherein the limiting heat flux increasing means is formed by opposing surfaces (14A) of the plate-like portions (14) facing each other. The evaporator (10) according to claim 3,
An evaporator (10), wherein a part of the facing surface (14A) is provided with a bulging part (14B) bulging toward the flow path part (11).

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