CN103969037B - A kind of anti-splash device for atomization mechanism development test platform - Google Patents

Abstract

The invention discloses a splash prevention device for a test platform for atomization mechanism research, comprising a side wall, a first-stage louver structure and a second-stage louver structure, and the side wall is used to fix and support the two-stage louver structure. At the same time, there is a rectangular groove at the bottom of the side wall; the first-stage louver structure is composed of several parallel blades, the blades are placed between the two side walls at an inclination angle, the top of the blade is flush with the top of the side wall, and the two ends of the blade are aligned with the two sides. The walls are fixed; the A-A section shape of the blade is a parallelogram, where the acute angle is equal to the blade inclination angle, and the head and tail of adjacent blades are in the same vertical plane. The secondary louver structure is composed of several parallel blades, and the blade inclination angle is placed Between the two side walls; the tip of the blade is located at the lower end of the blade; the two ends of the blade are fixedly connected to the two side walls; the cross-sectional shape of the blade A-A is a parallelogram, and the acute angle is the same as the inclination angle of the blade. The invention effectively prevents the phenomenon of splashing water, and at the same time further enhances the elimination of water mist during the test.

Description

A splash-proof device for the test platform of atomization mechanism research

technical field

The invention relates to the technical field of rocket engines, in particular to an anti-splashing device for a test platform for atomization mechanism research.

Background technique

The atomization performance of the nozzle directly affects the combustion efficiency of combustion devices such as rocket engines and air heaters, thereby affecting their performance. The liquid or two-phase flow medium is ejected from the nozzle, and generally goes through the continuous liquid film stage, the primary crushing stage and the secondary crushing stage. For each stage of nozzle atomization, domestic and foreign researchers have conducted detailed research, but in the atomization There is still no consensus on the mechanism.

Li Qinglian, Wu Liyin and others from the University of National Defense Science and Technology designed and built an atomization mechanism research test platform, using phase Doppler analyzer (PDA), laser particle size analyzer, high-speed camera and other advanced optical instruments to test the atomization performance of various nozzles commonly used in rocket engines. Conduct research to reveal the inner law of nozzle atomization.

Wu Liyin applied for the national patent of "Atomization Mechanism Research Test Platform" in 2012, the application number is 201210483054.9. as shown in picture 2. Pointing out that there is a problem of "fog lingering" in the atomization research, which affects the observation and measurement of the flow field, especially the use of optical equipment, and invented a method of mist suction to minimize the influence of the liquid mist on the test measurement during the nozzle atomization test . However, during the test, when the liquid flow rate is large and there is gas-assisted atomization, the liquid jet is concentrated and the speed is high, and the jet impacts the bottom of the drainage tank, resulting in a strong splashing phenomenon, and the water droplets splash and enter the measurement area to affect the atomization The measurement accuracy is high, and the splashed water droplets are easy to fly out of the spray collection tank of the test bench, thus affecting the environment of the test room.

Contents of the invention

The technical problem to be solved by the invention is: the water splash phenomenon exists in the use process of the atomization mechanism research test platform, which further affects the atomization measurement accuracy. The invention provides a splash-proof device used for a test platform for atomization mechanism research. Effectively prevent the occurrence of splashing water, and at the same time further enhance the elimination of water mist during the test, and improve the accuracy of atomization measurement.

The invention discloses a splash-proof device for a test platform for atomization mechanism research, comprising a side wall, a primary louver structure and a secondary louver structure, and the side wall is used to fix and support the two-stage louver structure. At the same time, there is a rectangular groove at the bottom of the side wall; the first-stage louver structure is composed of several parallel blades I, the blade I is placed between the two side walls at an inclination angle γ, and the top of the blade I is flush with the top of the side wall. The two ends of the blade I are fixedly connected to the two side walls; the A-A cross-sectional shape of the blade I is a parallelogram, wherein the acute angle α is equal to the inclination angle γ of the blade I, and the head and tail of the adjacent blades I are in the same vertical plane.

The two-stage louver structure is composed of several parallel blades II. The blade II is placed between the two side walls at an angle of 2γ; the top of the blade II is located at the lower end of the blade I; The cross-sectional shape is a parallelogram, where the acute angle is the same as the blade II inclination angle.

Preferably, the ratio of the length l of the inclined side of the parallelogram of the blade section to the height h corresponding to the side is in the range of 30-40.

The size of the blade meets the requirements of formulas 1 and 2 at the same time:

$\frac{\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; h</span>}}{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}<span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

$\frac{\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; \&CenterDot;</span>{\mathrm{<span\; class="notranslate">\; sin</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; h</span>}}{<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; the\; tan</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; h</span>}}{\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; l</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; i</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; h</span>}<span\; class="notranslate">\; /</span>\mathrm{<span\; class="notranslate">\; c</span>}\mathrm{<span\; class="notranslate">\; o</span>}\mathrm{<span\; class="notranslate">\; the\; s</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&alpha;</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; t</span>}\mathrm{<span\; class="notranslate">\; a</span>}\mathrm{<span\; class="notranslate">\; no</span>}\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; ></span>\mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

Section parallelogram inclined side length l, height h, acute angle α, jet 1/2 cone angle β.

The technical solution adopted in the present invention is: the main reason for the splashing of the water droplets is that the liquid has a large momentum and hits the undischarged water surface at the bottom of the gutter, causing the droplets to splash. The invention utilizes the louver structure so that the liquid jet at the outlet of the nozzle does not directly act on the liquid surface at the bottom of the drainage tank, and cooperates with the suction device to effectively prevent the occurrence of water splashing. When the liquid jet hits the primary louver structure at high speed, the droplets are broken into smaller droplets, and the direction of movement changes at the same time, and the droplets continue to move, or continue to hit the primary louver structure to continue breaking and turning, or Through the primary louver structure and then into the secondary louver structure, the droplets are either impacted and broken in the secondary louver structure and then enter the drainage groove, or directly enter the drainage groove through the secondary louver structure. At the same time, the liquid mist and small liquid droplets formed during the impact are sucked by the suction device to prevent the liquid mist and small liquid droplets from moving upward.

The beneficial effects are:

1. The present invention avoids the direct collision between the liquid jet and the liquid surface in the drainage tank. The jet breaks and turns when it collides with the first-level louver structure and the second-level louver structure. The liquid in the drainage tank is violently impacted, resulting in serious splashing;

2. The suction device sucks the fine droplets and liquid mist generated by the liquid jet during the impact and crushing process downward, so that the liquid mist will not rise and affect the measurement of the upstream test;

3. The suction device can also move larger droplets to the direction of the suction air flow to a certain extent, which plays a certain role in preventing the droplets from splashing upward during the crushing process;

4. Part of the liquid will still move upwards due to impact, crushing and backsplash in the drainage tank, but the total mass and momentum of this part of the liquid moving upwards are smaller than those before the anti-splash device is added, and due to the two-stage louver structure There are very few droplets that actually splash into the upstream and affect the measurement results. It is found in practical applications that there are almost no droplets in this part.

Description of drawings

Figure 1: Schematic diagram of the structure and working principle of the splash-proof device of the present invention

Figure 2: Schematic diagram of the structure of the diffuse spray suction mechanism of the prior art atomization mechanism research test platform.

Figure 3: Schematic diagram of the installation of the anti-splash device of the present invention in the test platform for atomization mechanism research

Figure 4: Structural diagram of the splash-proof device of the present invention

Figure 5: Structural diagram of the first-stage louver structure blade in the present invention

Figure 5a: Sectional view of Figure 3A-A

Figure 5b: Enlarged view of part M in Figure 5a

detailed description

The present invention will be described in detail below in conjunction with the accompanying drawings.

As shown in FIG. 4 , the anti-splash device of the present invention includes a side wall 21 , a primary louver structure 22 and a secondary louver structure 23 .

The side wall 21 is used to fix and support the two-stage louver structure, and a rectangular groove is opened at the bottom of the side wall for drainage.

The primary louver structure 22 is composed of several parallel blades I 221, the blade I 221 is placed between the two side walls 21 with an inclination angle γ, the top of the blade I 221 is flush with the top of the side wall 21, and the two ends of the blade I 221 are aligned with the two sides. Wall 21 is fixedly connected. The A-A cross-sectional shape of the blade I221 is a parallelogram, wherein the acute angle α is equal to the inclination angle γ of the blade I 221, so that one side of the quadrilateral cross-section after the blade I 221 is fixed to the side wall 21 remains vertical. Adjacent blades I 221 are in the same vertical plane from head to tail, such as BC and DE are collinear.

The determination of blade I 221 size and inclination angle γ follows the following principles: first, the ratio of the length l of the inclined side of the parallelogram in its section to the height h corresponding to the side is in the range of 30 to 40; The angle α is equal; three, the number of collisions between the liquid jet and the same blade I 221 is not more than one time; four, the liquid jet and the blade I 221 will not continue to collide in the vertical plane (DE) of the adjacent blade I 221 after impact reflection; five , the clogging ratio of the primary louver mechanism less than 0.2.

The specific calculation process is as follows:

Step 1: Determine the length l of the inclined side of the parallelogram in the section of the blade I 221 and the corresponding height h;

The second step: determine the blade inclination angle α and the acute angle of the section parallelogram. Assuming that the jet hits the blade I 221 at the maximum inclination angle β, that is, the jet flow is half of the cone angle, according to the requirements of principles 2, 3 and 4, it is necessary to meet the requirements of the jet hitting the top of the blade I 221 and then hit the The adjacent blade I 221 is inclined on the inclined surface and directly passes through the primary louver structure after being reflected again. Both of the following criteria must be satisfied:

Criterion one:

Judgment 2:

For example: take h=3mm l=90mm l/h=30, jet flow 1/2 cone angle β=5°, obtain blade I221 inclination angle γ=10°, its section parallelogram acute angle α=10°, adjacent The horizontal distance d between blades I 221 is 15.6mm, and the blockage ratio λ of the primary louver structure is 0.195. The obtained primary louver structure meets the design requirements.

The secondary louver structure 23 is composed of several parallel blades II231, and the blade II231 is placed between the two side walls 21 at an angle of 2γ; the top of the blade II231 is located at the lower end of the blade I 221; the two ends of the blade II231 are fixedly connected to the two side walls 21; The section shape of blade II231A-A is a parallelogram, wherein the acute angle is the same as the inclination angle of blade II231, so that one side of the quadrilateral in section after blade II231 is fixedly connected to side wall 21 remains vertical. Adjacent blades II231 are in the same vertical plane head to tail.

The size and inclination angle of the blade II231 follow the following principles: one, the inclination angle is twice the inclination angle of the blade I 221; two, the inclination angle is equal to the acute angle of the parallelogram section; 221 twice the horizontal spacing, and the blade II231 is always located directly below the blade I 221; Fourth, the ratio of the length l of the inclined side of the parallelogram of the blade II231 section to the height h corresponding to the side is in the range of 30-40.

For example: the top of the blade II 231 is located at 50 mm from the lower end of the blade I 221, its cross-sectional parallelogram has an acute angle of 20 degrees, its inclination angle is 20 degrees, the length of the sloped side is 91.4 mm, and the height corresponding to the sloped side is 3 mm. The adjacent blade II231 The horizontal distance between them is 31.2mm, and the blockage ratio of the secondary louver structure is 0.102.

The anti-splash device 2 is placed in the rectangular liquid mist collection tank 1, and the louver structure is placed on the side of the exhaust duct 11 in the direction of the downward slope.

The liquid jet collides with the louver structure in the present invention for many times, and the fine liquid mist is sucked and discharged from the exhaust duct 11 . The other part of the liquid is collected into the sump through the two-stage louver structure.

Although the embodiments of the present invention have been described with reference to the accompanying drawings, various variations or modifications may be made by those skilled in the art within the scope of the appended claims.

Claims (2)

1. for the anti-splash device of atomization mechanism development test platform, including sidewall (21), one-level louver structure (22) and Two grades of louver structures (23)；

Described sidewall (21) is used for fixing and support two-stage louver structure, and the bottom of sidewall has groove；

Described one-level louver structure (22) is made up of several parallel blades I (221), and blade I (221) angle of inclination γ is positioned over Between two sidewalls (21), blade I (221) top is concordant with sidewall (21) top, blade I (221) two ends and two side (21) It is connected；The Section A-A of blade I (221) is shaped as parallelogram, and the sharp angle α and blade I (221) of parallelogram incline Rake angle γ is equal, and adjacent blades I (221) head and the tail are in same perpendicular；

Described two grades of louver structures (23) are made up of several parallel blades II (231), and blade II (231) tilts 2 γ angles and puts It is placed between two sidewalls (21)；Blade II (231) top is positioned at the positive lower end of blade I (221)；Blade II (231) two ends and two Sidewall (21) is connected；Blade II (231) Section A-A is shaped as parallelogram, and wherein sharp angle tilts with blade II (231) Angle is identical；

Described blade I (221), the size of blade II (231) meet the requirement of formula 1,2 simultaneously:

$\frac{l\&CenterDot;sin\mathrm{\&alpha;}-h/cos\mathrm{\&alpha;}}{tan(2\mathrm{\&alpha;}+\mathrm{\&beta;})-tan\mathrm{\&alpha;}}-\frac{h}{sin\mathrm{\&alpha;}}>0---\left(1\right)$

$\frac{l\&CenterDot;{\sin }^2\mathrm{\&alpha;}-tan(2\mathrm{\&alpha;}+\mathrm{\&beta;})\&CenterDot;h}{\left(\tan \right(2\mathrm{\&alpha;}+\mathrm{\&beta;})-\tan \mathrm{\&alpha;})\&CenterDot;cos\mathrm{\&alpha;}}-(l\&CenterDot;cos\mathrm{\&alpha;}+\frac{h}{sin\mathrm{\&alpha;}}-\frac{l\&CenterDot;sin\mathrm{\&alpha;}-h/cos\mathrm{\&alpha;}}{tan(2\mathrm{\&alpha;}+\mathrm{\&beta;})-tan\mathrm{\&alpha;}})\&CenterDot;tan\mathrm{\&beta;}>0---\left(2\right)$

Cross section parallelogram inclined side length l, high h, sharp angle α, jet 1/2nd cone angle beta.

A kind of anti-splash device for atomization mechanism development test platform, it is characterised in that described The ratio range of the high h that blade (231,221) cross section parallelogram inclined side length l is corresponding with this limit is 30～40.