CN104852068A - Proton exchange membrane fuel cell bipolar plate distributing head and design method thereof - Google Patents

Abstract

The invention discloses a proton exchange membrane fuel cell bipolar plate distributing head and a design method thereof. The proton exchange membrane fuel cell bipolar plate distributing head comprises an air inlet and a diversion area, wherein one end of the diversion area is connected with the air inlet, the other end of the diversion area is connected with a runner of a bipolar plate, the diversion area comprises multiple diversion strips which are in Z-shape arrangement, and the air inlet direction of the air inlet is consistent to the extending direction of the runner. The diversion strips in Z-shape arrangement are embedded in the proton exchange membrane fuel cell bipolar plate distributing head, so airflow distribution uniformity in each channel of a proton exchange membrane fuel cell is improved, thus being beneficial to improving the performance of the proton exchange membrane fuel cell.

Description

A kind of dual polar plates of proton exchange membrane fuel cell dispensing head and method for designing thereof

Technical field

The present invention relates to Proton Exchange Membrane Fuel Cells technical field, be specifically related to a kind of dual polar plates of proton exchange membrane fuel cell dispensing head and method for designing thereof.

Background technology

Proton Exchange Membrane Fuel Cells (PEMFC) is considered to the ideal source of a kind of applicable human development and environmental requirement with advantages such as its high efficiency, high-energy-density, low stain.Wherein, bipolar plates is the vitals of PEMFC, and there is the runner processed on its two sides, and plays a part distribution reaction gas, collected current, mechanical support, hydro-thermal management and separates negative and positive polarization response gas.Bipolar plate structure reasonable in design, can improve the uniformity of reaction gas distribution in runner, makes membrane electrode all can obtain sufficient reaction gas everywhere, and the used heat of generation is discharged in time, ensure that fuel cell has good performance and stability.

In existing technology, the general air guide by adding different structure, different layout in bipolar plates dispensing head, changes the flow direction of reaction gas, makes the reaction gas entered in each runner distribute more even.In addition, along with the development of computer technology, CFD technology is also applied in fuel cell more and more, is instructed the design and optimization of fuel cell bipolar plate structure by flow field analysis.

Patent CN102013500A discloses a proton exchanging film fuel battery gas flowfield, and its bottom surface distributing flow field segments is provided with equally distributed oval dispensing head, improves the mass transport process of reacting gas.But because gas feed size is smaller, fewer away from distribution of gas in the runner of gas feed place, in bipolar plates, in each runner, the uniform property of gas is difficult to be guaranteed.

Summary of the invention

The embodiment of the present invention provides a kind of dual polar plates of proton exchange membrane fuel cell dispensing head and method for designing thereof, and the dual polar plates of proton exchange membrane fuel cell dispensing head designed improves flow distribution evenness in each runner of Proton Exchange Membrane Fuel Cells.

The embodiment of the present invention is by the following technical solutions:

First aspect, the technical program provides a kind of dual polar plates of proton exchange membrane fuel cell dispensing head, comprise air inlet and guiding region, one end of described guiding region is connected with described air inlet, the other end of described guiding region is connected with the runner of bipolar plates, described guiding region comprises many flow guide bars, and described flow guide bar is arrangement in " Z " font, and the airintake direction of described air inlet is consistent with described runner bearing of trend.

Its further technical scheme is, described flow guide bar comprises the first flow guide bar, the second flow guide bar and the 3rd flow guide bar, described first flow guide bar, the second flow guide bar and the 3rd flow guide bar near the position of described air inlet near to far arranging successively, the angle in described first flow guide bar and described inlet charge direction is the first angle, the angle in described second flow guide bar and described inlet charge direction is the second angle, described second angle is less than described first angle, and described 3rd flow guide bar is vertical with described inlet charge direction.

Its further technical scheme is, it is protruding that described first flow guide bar comprises multiple first water conservancy diversion, and it is protruding that described second flow guide bar comprises multiple second water conservancy diversion, and it is protruding that described 3rd flow guide bar comprises multiple 3rd water conservancy diversion.

Its further technical scheme is, protruding, the described second water conservancy diversion projection of described first water conservancy diversion and described 3rd water conservancy diversion projection are the one in cuboid, strip prismatoid and strip cylinder.

Its further technical scheme is, the height of described first water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 0.8 ~ 1mm; The height of described second water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm; The height of described 3rd water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm.

Its further technical scheme is, the distance on described first flow guide bar between adjacent two the first water conservancy diversion projections with apart from described air inlet near to far increasing gradually; Distance on described second flow guide bar between adjacent two described second water conservancy diversion projections with apart from described air inlet near to far increasing gradually; Distance on described 3rd flow guide bar between adjacent two described 3rd water conservancy diversion projections with apart from described air inlet near to far increasing gradually.

Its further technical scheme is that described runner is parallel to each other, and is linear pattern or waveform.

Second aspect, the technical program provides a kind of method for designing of dual polar plates of proton exchange membrane fuel cell dispensing head as described above,

By computer drawing software, three-dimensional steady state Mathematical Modeling is set up to described dual polar plates of proton exchange membrane fuel cell dispensing head and described runner;

Described Mathematical Modeling is imported CFD stress and strain model software, carry out perfect to described Mathematical Modeling, determine size of mesh opening and complete the division of grid, saving as grid file;

Described grid file is imported CFD software solve, set up governing equation, the boundary condition of definition computation model, given solution control parameter complete and calculate iterative process and obtain iterative computation result;

Described iterative computation result is processed, optimize described first flow guide bar of described dual polar plates of proton exchange membrane fuel cell dispensing head, the second flow guide bar and the 3rd flow guide bar and described inlet charge direction angle and described first water conservancy diversion is protruding, the second water conservancy diversion is protruding and the length of the 3rd water conservancy diversion projection and spacing.

The beneficial effect that the technical scheme that the embodiment of the present invention provides is brought:

In the technical program, by the flow guide bar in the embedded arrangement in " Z " font of dual polar plates of proton exchange membrane fuel cell dispensing head, improve flow distribution evenness in each raceway groove of Proton Exchange Membrane Fuel Cells, be conducive to the performance improving Proton Exchange Membrane Fuel Cells.

Accompanying drawing explanation

In order to be illustrated more clearly in the technical scheme in the embodiment of the present invention, below the accompanying drawing used required in describing the embodiment of the present invention is briefly described, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to the content of the embodiment of the present invention and these accompanying drawings.

Fig. 1 is the structural representation of the dual polar plates of proton exchange membrane fuel cell dispensing head that the embodiment of the present invention provides.

Fig. 2 is the spacing list between protruding adjacent two water conservancy diversion projections of three kinds of water conservancy diversion that the embodiment of the present invention provides.

Fig. 3 is the method for designing flow chart of the dual polar plates of proton exchange membrane fuel cell dispensing head that the embodiment of the present invention provides.

Fig. 4 is the result schematic diagram of the embodiment of the present invention.

Embodiment

The technical problem solved for making the present invention, the technical scheme of employing and the technique effect that reaches are clearly, be described in further detail below in conjunction with the technical scheme of accompanying drawing to the embodiment of the present invention, obviously, described embodiment is only the present invention's part embodiment, instead of whole embodiments.Based on the embodiment in the present invention, those skilled in the art, not making the every other embodiment obtained under creative work prerequisite, belong to the scope of protection of the invention.

Fig. 1 is the structural representation of the dual polar plates of proton exchange membrane fuel cell dispensing head that the embodiment of the present invention provides.As shown in Figure 1, this dual polar plates of proton exchange membrane fuel cell dispensing head comprises air inlet 10 and guiding region 20, one end of described guiding region 20 is connected with described air inlet 10, the other end of described guiding region 20 is connected with the runner 30 of bipolar plates, described guiding region 20 comprises many flow guide bars 21, the arrangement in " Z " font of described flow guide bar 21, the airintake direction of described air inlet 10 is consistent with described runner 30 bearing of trend.

The embodiment of the present invention is at the flow guide bar 21 of the embedded arrangement in " Z " font of dual polar plates of proton exchange membrane fuel cell dispensing head, air-flow is after flow guide bar 21 water conservancy diversion of guiding region 20, enter in each runner 30 comparatively uniformly, finally discharge from gas outlet 40, improve flow distribution evenness in each raceway groove of Proton Exchange Membrane Fuel Cells, be conducive to the performance improving Proton Exchange Membrane Fuel Cells.

Preferably, described flow guide bar 21 comprises the first flow guide bar 210, second flow guide bar 211 and the 3rd flow guide bar 212, described first flow guide bar 210, second flow guide bar 211 and the 3rd flow guide bar 212 near the position of described air inlet 10 near to far arranging successively, described first flow guide bar 210 is the first angle α with the angle of described air inlet 10 airintake direction, described second flow guide bar 211 is the second angle β with the angle of described air inlet 10 airintake direction, described second angle β is less than described first angle α, described 3rd flow guide bar 212 is vertical with described air inlet 10 airintake direction.

Preferably, described first flow guide bar 210 comprises multiple first water conservancy diversion projection 2100, and described second flow guide bar 211 comprises multiple second water conservancy diversion projection 2110, and described 3rd flow guide bar 212 comprises multiple 3rd water conservancy diversion projection 2120.Described first water conservancy diversion projection 2100, described second water conservancy diversion protruding 2110 and described 3rd water conservancy diversion projection 2120 are the one in cuboid, strip prismatoid and strip cylinder.The height of described first water conservancy diversion projection 2100 is 0.05 ~ 0.1mm, and length is 0.8 ~ 1mm; The height of described second water conservancy diversion projection 2110 is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm; The height of described 3rd water conservancy diversion projection 2120 is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm.Described runner 30 is parallel to each other, and is linear pattern or waveform.

Distance on described first flow guide bar 210 between adjacent two the first water conservancy diversion projections 2100 with apart from described air inlet 10 near to far increasing gradually; Distance on described second flow guide bar 211 between adjacent two described second water conservancy diversion projections 2110 with apart from described air inlet 10 near to far increasing gradually; Distance on described 3rd flow guide bar 212 between adjacent two described 3rd water conservancy diversion projections 2120 with apart from described air inlet 10 near to far increasing gradually.

In the present embodiment, Fig. 2 is the spacing list between protruding adjacent two water conservancy diversion projections of three kinds of water conservancy diversion that the embodiment of the present invention provides.Composition graphs 2, runner 30 is 24, and the shape of runner 30 is linear, and the width of runner 30 is 1.8mm, and the width of ridge 50 is 1.0mm, and the length of runner 30 is 70mm, and runner 30 long enough is conducive to ensureing that reaction gas fully reacts.The height of the first water conservancy diversion projection 2100 is 0.1mm, length is 1mm, first angle α is 88 °, distance between adjacent two the first water conservancy diversion projections 2100 has two kinds, be respectively 0.3mm and 0.5mm, distance between protruding 2100 adjacent two the first water conservancy diversion projections 2100 of half first water conservancy diversion of contiguous air inlet 10 is 0.3mm, and the distance between protruding 2100 adjacent two the first water conservancy diversion projections 2100 of second half first water conservancy diversion is 0.5mm, second water conservancy diversion protruding 2110 is highly 0.1mm, length is 1.2mm, second angle β is 86 °, distance between adjacent two the second water conservancy diversion projections 2110 has four kinds, be respectively 0.3mm, 0.5mm, 0.7mm and 1mm, distance from distance air inlet 10 from protruding 2110 adjacent two the second water conservancy diversion projections 2110 of nearly the second water conservancy diversion to far away 1/4th is 0.3mm, successively 1/4th the second water conservancy diversion projection 2110 between distance be 0.5mm, then the distance of the second water conservancy diversion projection 2110 of 1/4th is 0.7mm, the distance of the second water conservancy diversion projection 2110 of last 1/4th is 1mm.The height of the 3rd water conservancy diversion projection 2120 is 0.1mm, length is 1.2mm, distance between adjacent two the 3rd water conservancy diversion projections 2120 has 2 kinds, be respectively 0.7mm, 2mm, distance between from distance air inlet 10 from protruding 2120 adjacent two the 3rd water conservancy diversion projections 2120 of nearly the 3rd water conservancy diversion to half far away is 0.7mm, and the distance in addition between protruding 2120 adjacent two the 3rd water conservancy diversion projections 2120 of half the 3rd water conservancy diversion is 2mm.The present embodiment is only the individual instances of the technical program, not as the restriction to the technical program.

Fig. 3 is the method for designing flow chart of the dual polar plates of proton exchange membrane fuel cell dispensing head that the embodiment of the present invention provides.As shown in Figure 3, the method for designing of this dual polar plates of proton exchange membrane fuel cell dispensing head as described above comprises the following steps:

S100, by computer drawing software, three-dimensional steady state Mathematical Modeling is set up to described dual polar plates of proton exchange membrane fuel cell dispensing head and described runner.

CFD---computational fluid dynamics, first needs to carry out modeling, realizes the mapping of physical space to computer memory.What 3 d modeling software was conventional has the engineering software such as CATIA, UG (Unigraphics NX), Solidworks.

S101, described Mathematical Modeling is imported CFD stress and strain model software, carry out perfect to described Mathematical Modeling, determine size of mesh opening and complete the division of grid, saving as grid file.

CFD stress and strain model software has ANSYS ICEM-CFD, Gambit, CFD-Geom etc.Concrete use is no longer described in detail here, and detailed content please refer to related data.

S102, described grid file is imported CFD software solve, set up governing equation, the boundary condition of definition computation model, given solution control parameter complete and calculate iterative process and obtain iterative computation result.

S103, described iterative computation result to be processed, optimize described first flow guide bar of described dual polar plates of proton exchange membrane fuel cell dispensing head, the second flow guide bar and the 3rd flow guide bar and described inlet charge direction angle and described first water conservancy diversion is protruding, the second water conservancy diversion is protruding and the length of the 3rd water conservancy diversion projection and spacing.

Optimize described first flow guide bar of dual polar plates of proton exchange membrane fuel cell dispensing head, the second flow guide bar and the 3rd flow guide bar and described inlet charge direction angle and described first water conservancy diversion is protruding, after the length of the second water conservancy diversion projection and the 3rd water conservancy diversion projection and spacing, repeat step S101 to step S103, until the requirement of airflow uniform distribution sexual satisfaction Proton Exchange Membrane Fuel Cells properties of product in flow channels for proton exchange membrane fuel cells.

The embodiment of the present invention utilizes the structure of CFD technology to "the" shape flow guide bar to improve, and can improve the uniformity of reaction gas distribution in runner widely; The CFD method for designing of bipolar plates dispensing head can reduce the project cycle, saves production cost, and for structure optimization provides guidance, is conducive to the performance improving fuel cell.

Particularly, runner is parallel fluid channels, and model utilizes CFD software to carry out the division of grid, is research object, sets up governing equation, comprising with air after setting up:

Mass-conservation equation:

$\frac{\∂\mathrm{\ρ}}{\∂t}+\frac{\∂\left(\mathrm{\ρ}{u}_x\right)}{\∂x}+\frac{\∂\left(\mathrm{\ρ}{u}_y\right)}{\∂y}+\frac{\∂\left(\mathrm{\ρ}{u}_z\right)}{\∂z}=0$

Momentum conservation equation:

$\frac{\∂\left(\mathrm{\ρ}{u}_x\right)}{\∂t}+\▿\·\left(\mathrm{\ρ}{u}_x\stackrel{\→}{u}\right)=-\frac{\∂p}{\∂x}+\frac{\∂{\mathrm{\τ}}_{\mathrm{xx}}}{\∂x}+\frac{\∂{\mathrm{\τ}}_{\mathrm{yx}}}{\∂y}+\frac{\∂{\mathrm{\τ}}_{\mathrm{zx}}}{\∂z}+\mathrm{\ρ}{f}_x$

$\frac{\∂\left(\mathrm{\ρ}{u}_y\right)}{\∂t}+\▿\·\left(\mathrm{\ρ}{u}_y\stackrel{\→}{u}\right)=-\frac{\∂p}{\∂y}+\frac{\∂{\mathrm{\τ}}_{\mathrm{xy}}}{\∂x}+\frac{\∂{\mathrm{\τ}}_{\mathrm{yy}}}{\∂y}+\frac{\∂{\mathrm{\τ}}_{\mathrm{zy}}}{\∂z}+\mathrm{\ρ}{f}_y$

$\frac{\∂\left(\mathrm{\ρ}{u}_z\right)}{\∂t}+\▿\·\left(\mathrm{\ρ}{u}_z\stackrel{\→}{u}\right)=-\frac{\∂p}{\∂z}+\frac{\∂{\mathrm{\τ}}_{\mathrm{xz}}}{\∂x}+\frac{\∂{\mathrm{\τ}}_{\mathrm{yz}}}{\∂y}+\frac{\∂{\mathrm{\τ}}_{\mathrm{zz}}}{\∂z}+\mathrm{\ρ}{f}_z$

Energy conservation equation:

$\frac{\∂\left(\mathrm{\ρE}\right)}{\∂t}+\▿\·\left[\stackrel{\→}{u}(\mathrm{\ρE}+p)\right]=\▿\·[k_{\mathrm{eff}}\▿T-\underset{j}{\mathrm{\Σ}}{h}_j{J}_j+({\mathrm{\τ}}_{\mathrm{eff}}\·\stackrel{\→}{u})]+S_h$

Turbulence control equation:

$\frac{\∂}{\∂t}\left(\mathrm{\ρk}\right)+\frac{\∂}{\∂x_i}\left(\mathrm{\ρ}{\mathrm{ku}}_i\right)=\frac{\∂}{\∂x_j}\left[(\mathrm{\μ}+\frac{{\mathrm{\μ}}_t}{{\mathrm{\σ}}_k})\frac{\∂k}{\∂x_j}\right]+G_k+G_b-\mathrm{\ρ\ϵ}-Y_M+S_k$

$\frac{\∂}{\∂t}\left(\mathrm{\ρ\ϵ}\right)+\frac{\∂}{\∂x_i}\left(\mathrm{\ρ\ϵ}{u}_i\right)=\frac{\∂}{\∂x_j}\left[(\mathrm{\μ}+\frac{{\mathrm{\μ}}_t}{{\mathrm{\σ}}_k})\frac{\∂\mathrm{\ϵ}}{\∂x_j}\right]+C_{1\mathrm{\ϵ}}\frac{\mathrm{\ϵ}}{k}(G_k+C_{3\mathrm{\ϵ}}{G}_b)-C_{2\mathrm{\ϵ}}\mathrm{\ρ}\frac{{\mathrm{\ϵ}}^2}{k}+S_{\mathrm{\ϵ}}$

Mass-conservation equation, momentum conservation equation, energy conservation equation and turbulence control equation are conventional equation in the research of this area, no longer describe in detail herein.After setting up governing equation, the definition boundary condition of computation model, given solution control parameter complete calculating iterative process.Iterative computation result is processed, by the evaluation criterion of flow field analysis and the uniform property of flow, judges whether designed dispensing head meets design needs.If do not satisfied the demand, the step S101 in repetition accompanying drawing 3, to step S103, namely utilizes the structure of computer drawing software to existing bipolar plates dispensing head to improve and CFD numerical simulation again, till meeting design needs.Wherein, architecture advances aspect comprise described first flow guide bar of dual polar plates of proton exchange membrane fuel cell dispensing head, the second flow guide bar and the 3rd flow guide bar and described inlet charge direction angle and described first water conservancy diversion is protruding, the second water conservancy diversion is protruding and the length of the 3rd water conservancy diversion projection and spacing.

The evaluation criterion formula of the uniform property of flow is:

$\mathrm{\σ}=\sqrt{\frac{\underset{i=1}{\overset{n}{\mathrm{\Σ}}}{\left(\frac{q_i-\stackrel{\‾}{q}}{\stackrel{\‾}{q}}\right)}^2}{n}}$

Wherein, q _ithe flow of air in each runner, be the average discharge of air in all runners, n is the quantity of runner, and σ is less, illustrates that flow distribution of fluid is more even.As shown in Figure 4, be result of calculation schematic diagram.Curve with rectangular dots in figure indicates that left side air flow is bigger than normal, and right side flow is less than normal, σ=0.273 without the flow distribution situation in each runner of bipolar plates of flow guide bar; The curve of the circular point of band represents the flow distribution situation in each runner of bipolar plates containing flow guide bar that the embodiment of the present invention provides, and in each runner, the flow of air is more or less the same, σ=0.019.The dual polar plates of proton exchange membrane fuel cell dispensing head that the embodiment of the present invention provides can improve the uniformity that reaction gas distributes in runner greatly, has certain directive significance to the performance improving Proton Exchange Membrane Fuel Cells.

Above content is only preferred embodiment of the present invention, and for those of ordinary skill in the art, according to thought of the present invention, all will change in specific embodiments and applications, this description should not be construed as limitation of the present invention.

Claims (8)

1. a dual polar plates of proton exchange membrane fuel cell dispensing head, it is characterized in that, comprise air inlet and guiding region, one end of described guiding region is connected with described air inlet, the other end of described guiding region is connected with the runner of bipolar plates, described guiding region comprises many flow guide bars, and described flow guide bar is arrangement in " Z " font, and the airintake direction of described air inlet is consistent with described runner bearing of trend.

2. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 1, it is characterized in that, described flow guide bar comprises the first flow guide bar, second flow guide bar and the 3rd flow guide bar, described first flow guide bar, second flow guide bar and the 3rd flow guide bar near the position of described air inlet near to far arranging successively, the angle in described first flow guide bar and described inlet charge direction is the first angle, the angle in described second flow guide bar and described inlet charge direction is the second angle, described second angle is less than described first angle, described 3rd flow guide bar is vertical with described inlet charge direction.

3. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 2, it is characterized in that, it is protruding that described first flow guide bar comprises multiple first water conservancy diversion, and it is protruding that described second flow guide bar comprises multiple second water conservancy diversion, and it is protruding that described 3rd flow guide bar comprises multiple 3rd water conservancy diversion.

4. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 3, it is characterized in that, protruding, the described second water conservancy diversion projection of described first water conservancy diversion and described 3rd water conservancy diversion projection are the one in cuboid, strip prismatoid and strip cylinder.

5. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 3, is characterized in that, the height of described first water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 0.8 ~ 1mm; The height of described second water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm; The height of described 3rd water conservancy diversion projection is 0.05 ~ 0.1mm, and length is 1 ~ 1.2mm.

6. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 3, is characterized in that, the distance on described first flow guide bar between adjacent two the first water conservancy diversion projections with apart from described air inlet near to far increasing gradually; Distance on described second flow guide bar between adjacent two described second water conservancy diversion projections with apart from described air inlet near to far increasing gradually; Distance on described 3rd flow guide bar between adjacent two described 3rd water conservancy diversion projections with apart from described air inlet near to far increasing gradually.

7. dual polar plates of proton exchange membrane fuel cell dispensing head according to claim 3, is characterized in that, described runner is parallel to each other, and is linear pattern or waveform.

8. a method for designing for dual polar plates of proton exchange membrane fuel cell dispensing head as claimed in claim 7, is characterized in that,

By computer drawing software, three-dimensional steady state Mathematical Modeling is set up to described dual polar plates of proton exchange membrane fuel cell dispensing head and described runner;

Described Mathematical Modeling is imported CFD stress and strain model software, carry out perfect to described Mathematical Modeling, determine size of mesh opening and complete the division of grid, saving as grid file;

Described grid file is imported CFD software solve, set up governing equation, the boundary condition of definition computation model, given solution control parameter complete and calculate iterative process and obtain iterative computation result;

Described iterative computation result is processed, optimize described first flow guide bar of described dual polar plates of proton exchange membrane fuel cell dispensing head, the second flow guide bar and the 3rd flow guide bar and described inlet charge direction angle and described first water conservancy diversion is protruding, the second water conservancy diversion is protruding and the length of the 3rd water conservancy diversion projection and spacing.