CN208171081U - A kind of heat pipe heat accumulation heat exchanger of heat storage capacity variation - Google Patents

Abstract

The utility model provides a kind of heat pipe heat accumulation heat exchanger of heat storage capacity variation, including gravity assisted heat pipe, the heat pipe includes evaporation ends and condensation end, it is characterized in that, the evaporation ends are arranged in storage heater, and the storage heater is arranged in heat source, and the condensation end is arranged in the container of cold source, from the center of storage heater to the direction of the outer wall of storage heater, the heat storage capacity of the heat-storing material in storage heater gradually dies down.The utility model can be further improved heat storage capacity, can be realized being evenly heated for vertical pipe by taking the heat storage capacity of heat-storing material to gradually change.

Description

A kind of heat pipe heat accumulation heat exchanger of heat storage capacity variation

Technical field

The utility model relates to a kind of heat exchanger technology more particularly to a kind of heat pipe heat accumulation heat exchange for expanding evaporation end area Device.

Background technique

Hot pipe technique is George Ge Luofo of U.S. Los Alamos (Los Alamos) National Laboratory in 1963 One kind of (George Grover) utility model is known as the heat transfer element of " heat pipe ", it takes full advantage of heat-conduction principle and phase The heat of thermal objects, is transmitted to outside heat source rapidly by the quick thermal transport property for becoming medium through heat pipe, and the capacity of heat transmission is super Cross the capacity of heat transmission of any known metal.

The industries such as aerospace, military project were widely used in front of hot pipe technique, since being introduced into radiator manufacturing, so that People change the mentality of designing of traditional heat sinks, get rid of the list for obtaining more preferable heat dissipation effect by high air quantity motor merely One radiating mode makes radiator obtain satisfied heat transfer effect using hot pipe technique, opens heat dissipation industry new world.At present Heat pipe is widely used in various heat exchange equipments, including nuclear power field, such as the UTILIZATION OF VESIDUAL HEAT IN of nuclear power etc..

In the prior art, the shape of heat pipe affects the endotherm area of evaporation ends, therefore general evaporation ends heat absorption range ratio It is smaller, it sometimes needs that multiple heat pipes are arranged in heat source to meet heat absorption demand；And more evaporation ends there are when, it is each Evaporation ends can generate the non-uniform phenomenon of heat absorption because the position in heat source is different.

It is essentially all using gravity assisted heat pipe, and because of condensation end of heat pipe evaporation ends in current heat tube heat accumulator Caliber is identical, causes heating surface area small, can not preferably expand heat exchange area, therefore in view of the above-mentioned problems, the utility model exists It is improved on the basis of the utility model of front, provides a kind of new heat tube heat accumulator, by the variation of heat storage capacity, into One step improves heat transfer effect, makes full use of heat source, reduces energy consumption.

Utility model content

The utility model provides a kind of new heat pipe structure, guarantees that the heat absorption of evaporation ends is uniform, energy saving.

To achieve the goals above, the technical solution of the utility model is as follows：

A kind of heat pipe heat accumulation heat exchanger of heat storage capacity variation, including gravity assisted heat pipe, the heat pipe include evaporation ends and cold Solidifying end, which is characterized in that the evaporation ends are arranged in storage heater, and the storage heater is arranged in heat source, and the condensation end is set It sets in the container of cold source, from the center of storage heater to the direction of the outer wall of storage heater, the accumulation of heat of the heat-storing material in storage heater Ability gradually dies down.

Preferably, from the center of storage heater to the outer wall direction of storage heater, the heat storage capacity of heat-storing material gradually weakens Amplitude gradually increase.

Preferably, the heat source is geothermal energy.

Preferably, the fusing point of heat-storing material is 60-80 degrees Celsius in the storage heater.

Preferably, the heat-storing material in the storage heater is paraffin.

Preferably, the cross-sectional area of the storage heater is 10-26 times of vessel cross-sectional area.

Preferably, the heat pipe includes vertical portion, horizontal component and vertical pipe, wherein the bottom end connection of vertical portion Horizontal component, direction of the horizontal component from the bottom end of vertical portion away from vertical portion extend, the horizontal component Lower part is connected to multiple vertical pipes, and wherein vertical pipe is the evaporation ends of heat pipe, and vertical portion is the condensation end of heat pipe.

Preferably, the horizontal component is flat tube structure, vertical pipe is circular tube structure.

Preferably, horizontal component is square structure.

Preferably, the vertical pipe is multiple rows of, wherein adjacent two rows are to be staggered in arrangement.

Preferably, the center of circle of vertical pipe and two closed on the vertical pipe center of circle of adjacent row constitute isosceles triangle, institute State vertical pipe the center of circle be located at isosceles triangle apex angle point position.

Preferably, the outer diameter of vertical pipe is d, the distance between adjacent vertical pipe center of circle of same row is L, vertical pipe It is A that 3 center of circle and two closed on the vertical pipe center of circle of adjacent row, which constitute the apex angle of isosceles triangle, then meets claimed below：

Sin (A)=a-b*Ln (d/L), wherein Ln is logarithmic function, and a, b are parameters, meets following require：

0.095<a<0.105,0.29<b<0.31；0.1<d/L<0.7.

Preferably, gradually becoming smaller with d/L, a is increasing, and b is increasing.

Preferably, 15 °<A<80°.

Preferably, 20 °<A<40°.

Preferably, 0.2<d/L<0.5.

Compared with prior art, the utility model has the following advantages：

1) the utility model can be further improved accumulation of heat energy by taking the heat storage capacity of heat-storing material to gradually change Power can be realized being evenly heated for vertical pipe.Because more arriving storage heater outer wall, then because directly being contacted with heat source, herein Temperature highest, heat-storing material can be directly heated, and after heat-storing material is by abundant accumulation of heat, heat can be to the inside of storage heater Transmitting.Pass through the variation of the heat storage capacity of storage heater heat-storing material, it is ensured that after external heat-storing material reaches accumulation of heat saturation, meeting Heat is internally transmitted at once, guarantees that inside also stores heat.In this way, different location of the vertical pipe in storage heater can fill Divide heat absorption, the heat pipe overheat avoided, some heat pipe heat absorptions not enough, guarantee that the heat absorption of integral heat pipe is uniform, part is avoided to overheat Steam damage, causes the difficult in maintenance of product.It is arranged in this way, the service life that can be heat pipe entirety reaches identical.Together When make cold source also whole homogeneous heating.

2) the utility model is greater than the cross-sectional area of the container where cold source by the cross-sectional area of storage heater, can be into one The heat exchange area of the increase storage heater and heat source of step, and more heats can be stored, the requirement of further satisfaction heating.

3) structure of the evaporation ends of the utility model opposite heat tube is improved, and the evaporation ends of heat pipe is extended to farther It direction, in this way can be with so that the endotherm area of the evaporation ends of heat pipe increases in the case where not changing the condensation end volume of heat pipe The heat absorption range for expanding heat pipe, can be absorbed the heat of heat source distalmost end.Heat pipe evaporation ends in compared with the existing technology and cold Solidifying end is consistent size, can be improved 40% or more heat exchange efficiency.The volume and occupied area for reducing heat exchanger simultaneously, make It obtains compact-sized.

4) communicating pipe is arranged in adjacent evaporation ends in the utility model, can lead to pressure not in the heated difference of vertical pipe With in the case where, the fluid in evaporation ends that pressure can be made big quickly flows to the small evaporation ends of pressure, to keep whole Body pressure is balanced, avoids hot-spot or supercooling.

5) research of a large amount of numerical simulation and experiment has been carried out, distributed architecture of the opposite heat tube in storage heater has carried out most Excellent structure, and the best relative formula that heat pipe is distributed is obtained by research, the distribution of heat pipe is further increased, reaches optimal Heat absorption reduces cost.

6) communicating pipe is arranged in the utility model between adjacent heat pipe, realizes that the pressure between heat pipe is balanced, heat exchange is equal Weighing apparatus.

Detailed description of the invention

Fig. 1 is the utility model heat pipe structure schematic diagram.

Fig. 2 is schematic diagram of the Fig. 1 from bottom.

Fig. 3 is the heat pipe partial structural diagram that communicating pipe is arranged in the utility model.

Fig. 4 is the utility model heat pipe specific embodiment structural schematic diagram.

Fig. 5 is the structural schematic diagram that communicating pipe is arranged between the utility model heat pipe of Fig. 4.

Fig. 6 is the partial enlargement mark schematic diagram of Fig. 2.

In figure：8 communicating pipe of 1 vertical portion, 2 horizontal component, 3 vertical pipe, 4 storage heater, 5 cold source, 7 communicating pipe of 6 heat source 9 containers

Specific embodiment

Specific embodiment of the present utility model is described in detail with reference to the accompanying drawing.

Herein, if without specified otherwise, it is related to formula, "/" indicates that division, "×", " * " indicate multiplication.

Specific embodiment of the present utility model is described in detail with reference to the accompanying drawing.

A kind of heat pipe, including vertical portion 1, horizontal component 2 and vertical pipe 3, wherein the bottom end of vertical portion 1 is connected to horizontal Part 2, direction of the horizontal component 2 from the bottom end of vertical portion 1 away from vertical portion 1 extend, the horizontal component 2 Lower part is connected to multiple vertical pipes 3, and wherein vertical pipe 3 is the evaporation ends of heat pipe, and vertical portion 1 is the condensation end of heat pipe.

The utility model heat pipe absorbs heat in operation, by vertical pipe 3 from heat source, then the stream in vertical pipe 3 Body is evaporated, and enters vertical portion by horizontal component, then rejects heat to cold source in vertical portion, fluid carries out Condensation, enters back into vertical pipe 3 by the effect of gravity.

The structure of the evaporation ends by the way that heat pipe is arranged of the utility model opposite heat tube is improved, by the evaporation ends of heat pipe Farther direction is extended to, in the case where not changing the condensation end volume of heat pipe, so that the endotherm area of the evaporation ends of heat pipe Increase, the heat absorption range of heat pipe can be expanded in this way, the heat of heat source distalmost end can be absorbed.Heat in compared with the existing technology Pipe evaporation ends and condensation end are consistent size, can be improved 45% or more heat exchange efficiency.The volume of condensation end is reduced simultaneously And occupied area, so that compact-sized.

In addition, evaporation ends of the utility model by the multiple vertical pipes 3 of setting as heat pipe, so that each vertical pipe 3 is made The absorption of heat is added for independent absorbing pipe one by one, also increases the endotherm area of integral heat pipe evaporation ends.

Preferably, the heat source can be soil or boiler exhaust gas etc..

Preferably, the cold source is water or air.

Preferably, the horizontal component 2 is flat tube structure, vertical pipe 3 is circular tube structure.By the way that horizontal component is arranged For flat tube structure, the distribution of vertical pipe 3 can be increased, further increase the absorption of heat.

Further preferably, horizontal component 2 is square structure.

Preferably, as shown in Fig. 2, the vertical pipe 3 is multiple rows of, wherein adjacent two rows are to be staggered in arrangement.Pass through mistake Column arrangement, can be further improved the caloric receptivity of heat pipe.

Preferably, vertical pipe 3 is located at the extended line of the middle line of the center of circle connecting line segment of the adjacent upright pipe 3 of adjacent row On.I.e. two closed on vertical pipe, 3 center of circle in the center of circle of vertical pipe 3 and adjacent row constitutes isosceles triangle, the vertical pipe The center of circle is located at the position of the point of isosceles triangle apex angle.

Preferably, as shown in figure 3, communicating pipe 8 is arranged between at least two adjacent vertical pipes 3.It finds under study for action, During vertical section heat absorption, it may appear that the absorption heat of the absorbing pipe of different location is different, leads to the pressure between vertical pipe 3 Power or temperature are different, will lead to straightened portion pipe 3 in this way and are heated excessively high, cause the lost of life, once a vertical pipe 3 occurs Problem may cause the problem of entire heat pipe is not available.The utility model is by largely studying, adjacent vertical Communicating pipe 8 is arranged in pipe, can make big vertical of pressure in the case where vertical pipe is heated different to cause pressure different Fluid in pipe 3 quickly flows to the small vertical pipe 3 of pressure, to keep integral pressure balanced, avoids hot-spot or mistake It is cold.

Preferably, multiple communicating pipes 8 are arranged between adjacent vertical pipe 3 from 3 lower part of vertical pipe to 3 top of vertical pipe. By the way that multiple communicating pipes are arranged, fluid continuous counterpressure in heat absorption evaporation process is enabled to, guarantees entire vertical pipe Interior pressure is balanced.

Preferably, constantly reducing the distance between adjacent communicating pipe 8 from 3 lower part of vertical pipe to 3 top of vertical pipe.This Purpose is in order to which more communicating pipes are arranged, because of flowing up with fluid, fluid is constantly heated, as fluid is continuous It is heated, it is heated more and more uneven in different thermal-collecting tubes, therefore by above-mentioned setting, can guarantee in process fluid flow In reach as soon as possible pressure equilibrium.

Preferably, from 3 lower part of vertical pipe to 3 top of vertical pipe, the distance between adjacent communicating pipe ever-reduced width It spends increasing.It is found through experiments that, above-mentioned setting, can guarantee that more excellent in process fluid flow to reach pressure equal faster Weighing apparatus.This is also the optimal mode of communicating got and largely studying pressure changes in distribution rule.

Preferably, from 3 lower part of vertical pipe to 3 top of vertical pipe, the diameter of communicating pipe 8 is continuously increased.This purpose be for Setting guarantees bigger connection area, because of flowing up with fluid, fluid is constantly heated, as fluid is continuous It is heated, it is heated more and more uneven in different thermal-collecting tubes, therefore by above-mentioned setting, it can guarantee in process fluid flow Reach pressure equilibrium as soon as possible.

Preferably, the ever-increasing amplitude of the diameter of communicating pipe 8 is increasingly from 3 lower part of vertical pipe to 3 top of vertical pipe Greatly.Be found through experiments that, above-mentioned setting, can guarantee in process fluid flow it is more excellent faster reach pressure equilibrium.This It is the optimal mode of communicating got and largely studying pressure changes in distribution rule.

Fig. 4 illustrates a kind of heat pipe using system, preferably, as shown in figure 4, the vertical pipe 3 of heat pipe is arranged in accumulation of heat In device 4.The storage heater 4 is arranged in heat source.The heat source can be geothermal energy.

Preferably, the fusing point of heat-storing material is 60-80 degrees Celsius in the storage heater 4, preferably 65 degrees Celsius.

Preferably, the heat-storing material in the storage heater 4 is paraffin.

The utility model can be got up the heat storage in heat source 6 by setting storage heater 4, and because storage heater Hot melt it is bigger, therefore more heats can be stored, therefore heat pipe can more fully utilize the heat of dry heat source 6, And because setting storage heater, storage heater and 6 contact area of heat source are bigger, and can greatly reduce heat pipe and heat source 6 it Between thermal contact resistance, easy for installation, endothermic effect will be much better than heat pipe and individually be placed in heat source 6.Therefore it is stored by setting Hot device can greatly improve the heat absorption efficiency of heat pipe.It is found through experiments that, by the way that storage heater is arranged, can be improved 15-20%'s Heating efficiency can further save the energy.

Preferably, the heat source is the geothermal energy of xeothermic rock stratum, the cold source is water, and heat pipe is used for the exploitation of shale gas Middle heating water generates steam, introduces steam into rammell to carry out the exploitation of shale gas.

Preferably, the cross section of the storage heater 4 is square structure, the cross-sectional area of the storage heater 4 is greater than cold source The cross-sectional area of the container 9 at place.It is greater than the cross-sectional area of the container 9 where cold source by the cross-sectional area of storage heater 4, it can be with The further heat exchange area for increasing storage heater and heat source 6, and more heats can be stored, further satisfaction heating is wanted It asks.

Preferably, the cross-sectional area of the storage heater 4 and container 9 is square structure.The side length of storage heater 4, which is greater than, to be held The side length of device 9.

Preferably, the cross-sectional area of the storage heater 4 is 10-26 times of 9 cross-sectional area of container, preferably 18 times.

Preferably, from the center of storage heater 4 to the direction of the outer wall of storage heater, the storage of the heat-storing material in storage heater 4 Thermal energy power gradually dies down.

Gradually changing for the heat storage capacity of heat-storing material is taken, can be further improved heat storage capacity, it is vertical to can be realized Pipe 3 is evenly heated.Because more arriving storage heater outer wall, then because directly being contacted with heat source, temperature highest herein, accumulation of heat Material can be directly heated, and after heat-storing material is by abundant accumulation of heat, heat can be transmitted to the inside of storage heater.Pass through storage heater The variation of the heat storage capacity of heat-storing material, it is ensured that, can be inside by heat at once after external heat-storing material reaches accumulation of heat saturation Portion's transmitting guarantees that inside also stores heat.In this way, different location of the vertical pipe 3 in storage heater can sufficiently absorb heat, avoid Heat pipe overheat, the heat absorption of some heat pipes not enough, guarantees that the heat absorption of integral heat pipe is uniform, avoids part superheated steam from damaging, cause Product it is difficult in maintenance.It is arranged in this way, the service life that can be heat pipe entirety reaches identical.Make cold source also whole simultaneously Body homogeneous heating.

Preferably, from the center of storage heater 4 to the outer wall direction of storage heater 4, the heat storage capacity of heat-storing material gradually subtracts Weak amplitude gradually increases.By experiment and numerical simulation discovery, this set is taken, can be further improved the heat absorption of heat pipe The uniformity.

Preferably, communicating pipe, 8 quantity was continuously increased from the center of storage heater 4 to the outer wall direction of storage heater 4.This mesh Be in order to which more communicating pipes are arranged because amount of stored heat is most closer to the outer wall direction of storage heater 4, fluid is heated also more, Steam pressure in vertical pipe 3 is also bigger, therefore by above-mentioned setting, can guarantee to reach as soon as possible in fluid thermal histories Pressure is balanced.

Preferably, from the center of storage heater 4 to the outer wall direction of storage heater 4, communicating pipe the ever-increasing amplitude of 8 quantity It is increasing.It is found through experiments that, above-mentioned setting, can guarantee that more excellent in fluid thermal histories to reach pressure equal faster Weighing apparatus.This is also the optimal mode of communicating got and largely studying pressure changes in distribution rule.

As preferably from the center of storage heater 4 to the outer wall direction of storage heater 4, the diameter of communicating pipe 8 is continuously increased.This mesh Be in order to be arranged and guarantee bigger connection area because amount of stored heat is most closer to the outer wall direction of storage heater 4, fluid by Heat is also more, and the steam pressure in vertical pipe 3 is also bigger, therefore by above-mentioned setting, can guarantee in fluid thermal histories to the greatest extent Fast reaches pressure equilibrium.

Preferably, from the center of storage heater 4 to the outer wall direction of storage heater 4, the ever-increasing width of the diameter of communicating pipe 8 It spends increasing.It is found through experiments that, above-mentioned setting, can guarantee that more excellent in process fluid flow to reach pressure equal faster Weighing apparatus.This is also the optimal mode of communicating got and largely studying pressure changes in distribution rule.

Accumulation of heat paraffin is loaded in storage heater.Paraffin class phase change heat storage material have latent heat of phase change it is high, almost without Surfusion, melt when steam pressure is low, be not susceptible to chemical reaction and chemical stability preferably, without mutually separate and corrosion The advantages such as property and price are low, become the first choice of heat-storing material.Paraffin embeds vertical pipe 3.Vertical pipe 3, which absorbs, comes from storage heater The heat of interior paraffin realizes the heating to cold source in top vertical portion heat release.

Pass through numerical simulation and experiment discovery, the distance between vertical pipe 3, between distance and adjacent row including same row Distance cannot be too small, it is too small to will lead to that heat pipe distribution is excessive, cause the caloric receptivity of every heat pipe insufficient, it is excessive to will lead to heat pipe Distribution is very little, causes heat pipe to overheat, therefore the application sums up by a large amount of numerical simulation and experiment and carrys out heat pipe vertical pipe 3 The distribution of the optimization of distribution, the deficiency so that heat pipe can neither recept the caloric, and it is excessive to recept the caloric.

As shown in fig. 6, the outer diameter of vertical pipe 3 is d, the distance between adjacent 3 center of circle of vertical pipe of same row is L, is erected It is A that the center of circle of straight tube 3 and two closed on vertical pipe, 3 center of circle of adjacent row, which constitute the apex angle of isosceles triangle, then meets following It is required that：

Sin (A)=a-b*Ln (d/L), wherein Ln is logarithmic function, and a, b are parameters, meets following require：

0.095<a<0.105,0.29<b<0.31；

Further preferably, the a=0.1016, b=0.3043.

Preferably, gradually becoming smaller with d/L, a is increasing, and b is increasing.

Preferably, 15 °<A<80°.

Further preferably, 20 °<A<40°.

0.1<d/L<0.7, further preferably, 0.2<d/L<0.5.

Above-mentioned empirical equation is obtained by a large amount of numerical simulations and experiment, the structure obtained by above-mentioned relation formula, energy It is enough to realize the heat pipe structure optimized, and pass through verification experimental verification, error is substantially within 3%.

The heat absorption capacity 900-1100W of heat pipe, further preferably 1000W；

100-120 degrees Celsius of the temperature of heat source, further preferably 110 DEG C.

Heat pipe horizontal component shown in Fig. 2 is preferably square, side length be 400-600 millimeters, further preferably 500 Millimeter.

3 outside diameter d of vertical pipe is 9-12 millimeters, further preferably 11mm.

Preferably, as shown in figure 4, including two heat pipes in the system, the horizontal component 2 of described two heat pipes divides Do not extend by two symmetrical heat pipes of setting towards opposite direction, can absorb heat in different directions, meet the need of heat exchange It asks.

Preferably, as shown in figure 5, communicating pipe 7 is arranged between the vertical pipe 3 of two heat pipes adjacent to each other.By setting Communicating pipe is set, can be even to avoid uneven heating between heat pipe, it realizes that the pressure between heat pipe is balanced, avoids between different heat pipes Defect caused by uneven heating is even.

Preferably, constantly reducing the distance between adjacent communicating pipe 7 from 3 lower part of vertical pipe to 3 top of vertical pipe.This Purpose is in order to which more communicating pipes are arranged, because of flowing up with fluid, fluid is constantly heated, as fluid is continuous It is heated, it is heated more and more uneven in different heat pipes, therefore by above-mentioned setting, can guarantee in process fluid flow Reach pressure equilibrium as soon as possible.

Preferably, from 3 lower part of vertical pipe to 3 top of vertical pipe, the distance between adjacent communicating pipe 7 ever-reduced width It spends increasing.It is found through experiments that, above-mentioned setting, can guarantee that more excellent in process fluid flow to reach pressure equal faster Weighing apparatus.This is also the optimal mode of communicating got and largely studying pressure changes in distribution rule.

Preferably, from 3 lower part of vertical pipe to 3 top of vertical pipe, the diameter of communicating pipe 7 is continuously increased.This purpose be for Setting guarantees bigger connection area, because of flowing up with fluid, fluid is constantly heated, as fluid is continuous It is heated, it is heated more and more uneven in different heat pipes, therefore by above-mentioned setting, it can guarantee in process fluid flow to the greatest extent Fast reaches pressure equilibrium.

Preferably, the ever-increasing amplitude of the diameter of communicating pipe 7 is increasingly from 3 lower part of vertical pipe to 3 top of vertical pipe Greatly.Be found through experiments that, above-mentioned setting, can guarantee in process fluid flow it is more excellent faster reach pressure equilibrium.This It is the optimal mode of communicating got and largely studying pressure changes in distribution rule.

Although the utility model has been disclosed in the preferred embodiments as above, the utility model is not limited to this.Any Field technical staff can make various changes or modifications without departing from the spirit and scope of the utility model, therefore this is practical Novel protection scope should be defined by the scope defined by the claims..

Claims (2)

1. a kind of heat pipe heat accumulation heat exchanger of heat storage capacity variation, including gravity assisted heat pipe, the heat pipe include evaporation ends and condensation End, which is characterized in that the evaporation ends are arranged in storage heater, and the storage heater is arranged in heat source, the condensation end setting In the container of cold source,

The heat pipe includes vertical portion, horizontal component and vertical pipe, and wherein the bottom end of vertical portion is connected to horizontal component, described Direction of the horizontal component from the bottom end of vertical portion away from vertical portion extends, and the horizontal component lower part connection is multiple perpendicular Straight tube, wherein vertical pipe is the evaporation ends of heat pipe, and vertical portion is the condensation end of heat pipe；

The vertical pipe is multiple rows of, wherein adjacent two rows are to be staggered in arrangement；

The center of circle of vertical pipe and two closed on the vertical pipe center of circle of adjacent row constitute isosceles triangle, the center of circle of the vertical pipe Positioned at the position of the point of isosceles triangle apex angle；

The outer diameter of vertical pipe be d, the distance between adjacent vertical pipe center of circle of same row be L, the center of circle of vertical pipe 3 with it is adjacent The apex angle that two closed on the vertical pipe center of circle of row constitutes isosceles triangle is A, then meets claimed below：

Sin (A)=a-b*Ln (d/L), wherein Ln is logarithmic function, and a, b are parameters, meets following require：

0.095<a<0.105,0.29<b<0.31；0.1<d/L<0.7.

2. heat exchanger as described in claim 1, which is characterized in that with gradually becoming smaller for d/L, a is increasing, and b is increasingly Greatly.