CN201258798Y

CN201258798Y - Heat pipe EGR cooler

Info

Publication number: CN201258798Y
Application number: CNU2008200883669U
Authority: CN
Inventors: 陆国栋; 安晓平; 陈子强; 张文锋; 张首都
Original assignee: Zhejiang Yinlun Machinery Co Ltd
Current assignee: Zhejiang Yinlun Machinery Co Ltd
Priority date: 2008-06-12
Filing date: 2008-06-12
Publication date: 2009-06-17
Anticipated expiration: 2018-06-12

Abstract

The utility model discloses a heat pipe type EGR cooler, which mainly comprises a shell and a heat pipe. The two ends of the shell are respectively provided with a waste gas inlet and a waste gas outlet. The heat pipe comprises a heating coil section, a steam pipe, a condensation segment and a condenser tube which are sequentially communicated end to end, and is characterized in that the heating coil section is arranged in the shell. The cooler uses the principle that the heat pipe technique is adopted for cooling; the cooling-down method can reduce waste gas temperature to be lower, and can effectively ease the influence of the waster gas on the performance per liter of an engine in the premise of the same recirculation waste gas quantity. Meanwhile, the cooler can effectively relieve the negative effect of heat exchanger effectiveness reduction brought about by caking and also can effectively avoid the leakage of the welding line between the shell and a waste gas inlet and outlet flange face.

Description

Hot pipe EGR cooler

Technical field

The utility model relates to a kind of gas quench system, is a kind of cooler for recycled exhaust gas specifically.It can be widely used on the power plant that use exhaust gas recirculation.

Background technique

Along with the increasingly stringent of emission request, EGR Technology is applied on the power plant more and more.The base principle is that the part waste gas that will discharge is for the first time led the generation that postbacks in the motivation with effective reduction nitrogen oxides from exhaust gas again after cooling.Cooler in traditional exhaust gas recirculation (EGR) process divides two kinds of shell of pipe type and plate and fin type.Mainly have following drawback: 1, traditional waste gas type of cooling utilizes engine coolant to cool off, because the cooling liquid of steam condition can cause serious cavitation erosion to engine cooling circuit, therefore engine coolant always exists with liquid form down in working order, that is to say that the waste gas cooling is to take away heat by the mode of engine coolant temperature rise, this mode cooling effect is relatively poor.2, conventional cooler for recycled exhaust gas adopts shell of pipe type or plate-fin structure, and the easier knot charcoal of compact structure can reduce the cooling effectiveness of cooler for recycled exhaust gas greatly.3, traditional shell of pipe type cooler for recycled exhaust gas, tube bank and the both sides end plate weld stress that is heated is obvious, easily leaks.4, traditional shell of pipe type cooler for recycled exhaust gas, exhaust flow is to flowing to identically with cooling liquid, and purpose is to reduce cooling liquid vaporization degree, but the cooling effect of following current is good not as adverse current.

Summary of the invention

To be solved in the utility model is the above-mentioned defective that prior art exists, aim to provide a kind of new cooler for recycled exhaust gas, cooled exhaust gas temperature can be reduced effectively, under the prerequisite of same EGR gas amount, the influence that waste gas causes HP, hp/litre can be effectively alleviated.Can effectively reduce the negative effect that the knot charcoal brings.The negative effect that spring-like bringing-up section structure can effectively be avoided expanding with heat and contract with cold and cause, housing more can expand with heat and contract with cold equably, significantly reduces the leakage chance of housing and flange face of weld.

The technological scheme that addresses the above problem employing is: a kind of hot pipe EGR cooler, mainly comprise housing and heat pipe two-part, described housing two ends are established exhaust gas inlet and waste gas outlet respectively, described heat pipe is made up of bringing-up section, steam tube, condensating section, the condensation tube of head and the tail connection successively, it is characterized in that described bringing-up section is arranged in the described housing.

Because the refrigerating function of heat pipe, to take away heat and realize by the vaporization of being heated of the cooling liquid in the bringing-up section, the exchange capability of heat of this heat exchange mode mode of taking away heat that heats up than being heated with liquid coolant is high more than 100 times.So the utility model is abandoned the mode of using the engine coolant cooling, and adopts independently heat pipe heat exchanging system, the effect of its cooled engine waste gas obviously is better than traditional cooler for recycled exhaust gas.And the condensed fluid in the heat pipe need not to add the driving force of pump, can circulate voluntarily according to the physical property of each state of material, has effectively saved the energy, and has simplified the structure of machine.

In the utility model, described housing is cylindrical tubular, is connected by flange between the exhaust gas inlet at its two ends and waste gas outlet and engine exhaust pipe and the muffler.Described heat pipe bringing-up section is double-deck cylindricality helical and arranges at the inner chamber of described housing, adopts the purpose of this structure, is crooked bringing-up section body on the one hand, has increased bringing-up section heat exchange working surface area effectively; On the other hand, the spring-like of body layout can make it freely stretch when body expands with heat and contract with cold, and can rhegma.And body flexible can also impel, and carbon deposit of prolong knot comes off on it.For increasing condensation effect, described condensating section is circuitous shape setting.

In the utility model, realize good orientation circulation in order to make cooling liquid, the interface of described condensating section and described steam tube should be higher than the interface with described condensation tube.

As further improvement of the utility model, the flow direction of cooling liquid and the interior exhaust flow of housing are to opposite in the described heat pipe bringing-up section.The design of this waste gas and the mutual reverse flow of cooling liquid helps abundant heat exchange.Its specific implementation can be, described steam tube and described bringing-up section interface are positioned at the exhaust gas inlet end of housing, and described condensation tube and described bringing-up section interface are positioned at the waste gas outlet end of housing.Because near one section of exhaust gas inlet and bigger near a section temperature difference of waste gas outlet, this arrangement helps medium natural circulation in the heat pipe in the housing.

Hot pipe EGR cooler advantage of the present utility model is as follows: 1, utilize the latent heat of vaporization of cooling liquid to cool off, exchange capability of heat is compared with conventional cooling liquid and can be improved more than 100 times, that is to say, lower through the cooled exhaust gas temperature of the utility model cooler, under before this, inscribing, the waste gas of same amount returns in the motor after the cooling of the utility model cooler can take littler space, has so just effectively reduced the influence of exhaust gas recirculation to HP, hp/litre.2, to walk the mode of shell side opposite with traditional cooling liquid, the waste gas narrow and small heat exchanging tube of pipeline of not gone further in the utility model, but pass through from the housing inner chamber.This employing waste gas is walked the method for shell side, because bringing-up section is the spring-like assembling structure, the carbon deposit that easier order is attached to tube-surface when expanding with heat and contract with cold breaks, comes off, and has automatic carbon removal function, can reduce the negative effect that the knot charcoal brings greatly.3, heat pipe bringing-up section of the present utility model adopts the design of spring-like helix structure, and its horizontal free stretchability is stronger, can effectively cushion the influence of thermal stress.4, the adverse current form is more conducive to waste gas and cooling liquid is carried out heat exchange.

Description of drawings

Fig. 1 is conventional shell of pipe type cooler for recycled exhaust gas schematic representation.

Fig. 2 is the hot pipe EGR cooler structural representation.

Fig. 3 is the front view of Fig. 2.

Fig. 4 is the left view of Fig. 2.

Fig. 5 is the right elevation of Fig. 2.

Fig. 6 is that the heat pipe section MEDIA FLOW is to schematic representation.

Fig. 7 is that the housing parts exhaust flow is to schematic representation.

Fig. 8 is the hot pipe EGR cooler External view.

Embodiment

With reference to Fig. 1, this figure is depicted as a kind of shell of pipe type traditional E GR cooler, and it comprises that the side is provided with the housing 2 of cooling liquid inlet 3 and outlet 4, be arranged in parallel and leaves each other one group of heat exchanging tube 1 in gap in housing 2.Described heat exchanging tube 1 is connected in the engine exhaust recirculation circuit by suction flange 5 and outlet(discharge) flange 6.And engine coolant enters described housing 2 inner chambers from described cooling liquid inlet 3 after being drawn by pipeline, flows out from cooling liquid outlet 4 then, sends back to engine-cooling system by pipeline again.In this structure, in order to reach better heat exchange effect, generally all much and very thin, in the narrow and small pipeline in heat exchanging tube, the knot carbon of inner tube wall can be easy to blocking pipe to described heat exchanging tube 1, and cooler for recycled exhaust gas was lost efficacy.

With reference to Fig. 2,3,4,5, the hot pipe EGR cooler that the utility model relates to is made up of heat pipe and housing 11 two-part.Wherein said heat pipe comprises bringing-up section 12, steam tube 8, cooling section 7 and condensation tube 9; Described housing 11 two ends are established exhaust gas inlet 10 and outlet 13 respectively.Described bringing-up section 12 is arranged on the inner chamber of described housing 11.Described steam tube 8 and condensation tube 9 are connected to described bringing-up section 12 two ends, upwards pass from housing 11 sides then.Be connected to cooling section 7 two ends again.Described cooling section 7 is arranged on housing 11 tops.Owing to only be connected with condensation tube 9 between described heat pipe bringing-up section 12 and cooling section 7 and the housing 11, and bringing-up section 12 and cooling section 7 are unsettled free end, so the stress of its generation can be eliminated voluntarily by steam tube 8.

With reference to Fig. 6, the bringing-up section 12 of described heat pipe bends to the double-layer spring shape, and described steam tube 8 is connected its left end, and described condensation tube 9 connects its right-hand member.Described cooling section 7 is bent into circuitous shape, and described steam tube 8 is positioned at the left end the top with its joint 16, and described condensation tube 9 and its joint 17 are positioned at below of right-hand member.---steam tube---cooling section---condensation tube---bringing-up section that this shows that the loop direction of cooling liquid in heat pipe is bringing-up section.Here, described heat pipe bringing-up section 12 adopts three flow process forms, and cooling liquid is contacted with waste gas more fully, absorbs the heat in the waste gas better, to ensure that medium is fully vaporized in the heat pipe.

With reference to Fig. 7, described housing 11 cylindrical straight-tube shapes, its two ends, left and right sides are communicated with engine exhaust pipe and muffler by suction flange 14 and outlet(discharge) flange 15 respectively.Described waste gas at the flow direction of housing 11 for from left to right.

In conjunction with Fig. 6 and Fig. 7 as can be known, cooling liquid mainly flows to contrary in waste gas and the heat pipe in hot pipe EGR cooler of the present utility model, as shown in Figure 8.This heat exchange of being more convenient for fully realizing.

What should be understood that is: above-mentioned mode of execution is just to explanation of the present utility model, rather than to restriction of the present utility model, any innovation and creation that do not exceed in the utility model spirit scope all fall within the protection domain of the present utility model.

Claims

1, a kind of hot pipe EGR cooler, mainly comprise heat pipe and housing (11) two-part composition, described housing (11) two ends are established exhaust gas inlet (10) and waste gas outlet (13) respectively, described heat pipe is made up of the bringing-up section that is connected to end successively (12), steam tube (8), cooling section (7) and condensation tube (9), it is characterized in that the bringing-up section of described heat pipe (12) is arranged in the described housing (11).

2, hot pipe EGR cooler according to claim 1 is characterized in that, described housing (11) is cylindrical tubular, and the exhaust gas inlet at its two ends (10) is connected by flange (14,15) with muffler with engine exhaust pipe respectively with waste gas outlet (13).

3, hot pipe EGR cooler according to claim 1 is characterized in that, described heat pipe bringing-up section (12) is the inner chamber that double-deck cylindricality helical is arranged in described housing (11).

According to the described hot pipe EGR cooler of claim 1, it is characterized in that 4, described steam tube (8) and condensation tube (9) pass from described housing (11) side, and fixing with it.

5, hot pipe EGR cooler according to claim 1 is characterized in that, described cooling section (7) is arranged on described housing (11) top.

According to each described hot pipe EGR cooler of claim 1-5, it is characterized in that 6, the interface of described cooling section (7) and described steam tube (8) is higher than the interface with described condensation tube (9).

7, hot pipe EGR cooler according to claim 6 is characterized in that, the flow direction of the interior cooling liquid of described heat pipe bringing-up section (12) and the interior exhaust flow of housing (11) are to opposite.

8, hot pipe EGR cooler according to claim 7, it is characterized in that, the interface of described steam tube (8) and described bringing-up section (12) is positioned at the exhaust gas inlet end of housing (11), and the interface of described condensation tube (9) and described bringing-up section (12) is positioned at the waste gas outlet end of housing (11).