Spontaneous combustion propellant liquid phase ignition test system with variable environmental parameters

Abstract

The utility model discloses a spontaneous combustion propellant liquid phase ignition test system with variable environmental parameters. The system comprises a device main body, a liquid drop generator and a high-speed imaging system, the device body is a stainless steel box body, and two glass windows are formed in the lower portion of the stainless steel box body. The stainless steel box body is a movable end cover capable of being opened, and a liquid injection hole is formed in the movable end cover and used for installing the liquid drop generator. An air inlet and an air outlet are respectively formed in two opposite side walls of the stainless steel box body; a liftable objective table is arranged at the bottom in the stainless steel box body, and a culture dish is arranged on the liftable objective table; a gas component monitor is arranged outside the stainless steel box body; and the high-speed imaging system is used for acquiring images during testing in real time through the glass window. The utility model can solve the problems that the traditional dropping method cannot realize high pressure and eliminate the interference of oxygen in the environment, and is difficult to accurately reflect the ignition performance of the spontaneous combustion type propellant under the real working condition and the safety in the experiment process by adopting a dangerous oxidizing agent, and the like.

Description

Technical Field

[0001] The utility model belongs to the field of fuel for aerospace equipment, and in particular relates to a self-igniting propellant liquid phase ignition test system with variable environmental parameters. Background Art

[0002] Hypergolic liquid propellants ignite through contact between fuel and oxidizer, without the need for complex ignition systems and external energy. They have the advantages of pulsed ignition and controllable thrust, and are widely used in attitude and orbit control systems of rockets and missiles. Hypergolic propellant fuel / oxidizer is dripped into the oxidizer / fuel liquid pool in the form of droplets, and the entire process of droplet falling, droplet contact with the liquid pool, and spontaneous combustion is photographed by high-speed photography, so that the ignition delay time that characterizes the propellant's self-ignition performance can be obtained.

[0003] Traditional falling drop method experiments are conducted in open space on the ground. It is believed that the self-ignition reaction of the propellant is mainly dominated by the chemical reaction between the fuel and the oxidant, and the influence of the environmental atmosphere such as the presence of oxygen in the air is ignored. However, there is a strong chemical reaction between the fuel vapor and the gaseous intermediate products produced after the contact between the fuel and the oxidant and the exothermic liquid phase pre-reaction and the oxygen in the environment, which directly affects the ignition process and ignition time of the propellant. At the same time, a large number of secondary droplets will splash outward during the reaction process. Most of these droplets are oxidants. Some oxidants, such as white fuming nitric acid (WFNA), are extremely corrosive and will cause damage to the health of the experimenters once they come into contact with the human body. The actual working environment of the self-igniting propellant is quite different from the ground environment. The traditional falling drop method cannot achieve high pressure and eliminate the interference of oxygen in the environment. It is difficult to accurately reflect the ignition performance of the self-igniting propellant under real working conditions. Utility Model Content

[0004] The utility model aims to provide a hypergolic propellant liquid phase ignition test system with variable environmental parameters, so as to solve the problems that the traditional falling drop method cannot achieve high pressure and eliminate the interference of oxygen in the environment, it is difficult to accurately reflect the ignition performance of the hypergolic propellant under real working conditions and the safety of the experimental process using dangerous oxidants.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A hypergolic propellant liquid phase ignition test system with variable environmental parameters, comprising a device body, a droplet generator and a high-speed imaging system;

[0007] The main body of the device is a stainless steel box, and two glass windows are provided at the bottom of the stainless steel box for visually photographing the ignition process of the internal droplets; the stainless steel box is an openable movable end cover, and a liquid injection hole is provided on the movable end cover for installing the droplet generator;

[0008] An air inlet and an exhaust port are respectively installed on two opposite side walls of the stainless steel box; a liftable loading platform is arranged at the bottom of the stainless steel box, and a culture dish is arranged on the liftable loading platform; a gas component monitor is arranged outside the stainless steel box to monitor the gas components in the stainless steel box;

[0009] The high-speed imaging system is used to collect images during testing in real time through the glass window.

[0010] A further improvement of the utility model is that an O-ring is arranged between the movable end cover and the upper end surface of the stainless steel box body for sealing.

[0011] A further improvement of the utility model is that the movable end cover and the stainless steel box body are fixed by means of quick clamps.

[0012] A further improvement of the utility model is that the droplet generator and the movable end cover are sealed by an O-ring.

[0013] A further improvement of the utility model is that the droplet generator is fixed to the movable end cover by bolts.

[0014] A further improvement of the utility model is that the gas component monitor comprises a gas component content sensor arranged in a stainless steel box body, and an external monitor arranged outside the stainless steel box body, and the gas component content sensor is connected to the external monitor.

[0015] A further improvement of the utility model is that both the air inlet and the air outlet are provided with valves.

[0016] A further improvement of the utility model is that a pressure gauge is also arranged on the side wall of the stainless steel box.

[0017] A further improvement of the utility model is that a fan is also arranged on the side wall of the stainless steel box.

[0018] A further improvement of the utility model is that the high-speed imaging system includes a high-speed camera, a zoom lens / telephoto microscope lens and a light source; the light source is used to emit scattered light to illuminate the target object, and the high-speed camera obtains the target object information through the zoom lens / telephoto microscope lens to form a video file, which can be viewed through a computer.

[0019] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0020] (A) Quantitative control of the ambient gas in the box is achieved through gas component content sensors and inert gas scavenging;

[0021] (B) Quantitative control of ambient pressure in the drop experiment is achieved through a pressure gauge;

[0022] (C) Install a fan inside the box to achieve rapid mixing of the gas inside the box;

[0023] (D) The safety of the experiment is improved by isolating the experimenters from the oxidant liquid pool through a closed box and using a glass syringe and a stainless steel needle to replace the oxidant liquid pool. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the device structure of the utility model.

[0025] Description of reference numerals:

[0026] 1-air inlet; 2-exhaust port; 3-glass window; 4-droplet generator; 5-culture dish; 6-liftable stage; 7-gas component monitor; 8-light source; 9-high-speed camera; 10-fan; 11-pressure gauge; 12-stainless steel box. DETAILED DESCRIPTION

[0027] The utility model is further described below in conjunction with the accompanying drawings.

[0028] like Figure 1 As shown, the utility model provides a hypergolic propellant liquid phase ignition test system with variable environmental parameters, including a device body, a droplet generator and a high-speed imaging system, which aims to accurately explore the influence of environmental parameters such as oxygen concentration on the ignition behavior of hypergolic propellant.

[0029] The main body of the device is a stainless steel box. Two glass windows are opened at the bottom of the box to visualize the ignition process of the internal droplets, and it can withstand a certain internal pressure. The upper part of the box is an openable movable end cover, which is sealed with an O-ring between the upper end face of the box and fixed by a quick clamp. An injection hole is opened on the upper part of the movable end cover, which can be used to inject liquid oxidant / fuel and install a droplet generator. The droplet generator and the movable end cover are sealed with an O-ring; the droplet generator and the movable end cover are fixed with bolts. The upper and lower diagonals of the stainless steel box are respectively installed with air intake and exhaust pipes to sweep the original gas in the box and enter the environment atmosphere of the specified pressure. A lifting stage is placed at the bottom of the stainless steel box to adjust the height between the liquid level in the culture dish and the droplet generator, thereby controlling the speed of the droplet when it collides with the liquid pool. In addition, a gas component content sensor (such as an oxygen content sensor) is installed at the bottom of the box and connected to an external monitor to read the component content in the box in real time, providing stable environmental conditions for the experiment. The pressure gauge installed on the box is used to read the pressure value in the box in real time. A fan is also installed inside the box to accelerate the mixing of gas atmosphere in the box and increase the speed of scavenging. In addition, a ball valve is installed on the lower side of the box for fast and effective exhaust to ensure the rapid update of the experimental environment.

[0030] The spontaneous combustion reaction of fuel and oxidant is usually very violent. In order to avoid the damage to the human body caused by the splash of droplets and to avoid the influence of oxidant dilution on the experimental results, glass syringes and long stainless steel needles are used to replace the oxidant liquid pool. The glass syringe is used to prevent the corrosion of the syringe by the oxidant, and the long stainless steel needle is used to reduce the splash of droplets. Under the control of the generator, the droplets fall freely into the center of the oxidant liquid pool located in the culture dish at a speed close to zero. By adjusting the distance between the droplet generator and the surface of the liquid pool, the collision speed of the droplets can be precisely controlled.

[0031] The high-speed imaging system includes a high-speed camera, a zoom lens / telephoto microscope lens and a light source. The light source emits scattered light to illuminate the target object, providing a good field of view. The high-speed camera obtains the target information through the zoom lens / telephoto microscope lens to form a video file, which can be viewed through a computer. Through the high-speed camera and the adapted lens, the dynamic behavior of the droplet and the detailed image of the ignition moment can be captured, providing an important experimental basis for subsequent data analysis and theoretical research.

[0032] Before each experiment, the oxidant in the oxidant liquid pool is replaced to ensure the consistency of the oxidant concentration, thereby minimizing the experimental error. Subsequently, the gas flow rate is adjusted and the gas composition is monitored to ensure the stability of the experimental environment. Finally, the droplets are released through the droplet generator, and the entire ignition process is recorded using a high-speed imaging system. Through this design, the utility model can study the liquid phase ignition characteristics of hypergolic propellants in detail under controllable environmental parameters.

[0033] The utility model provides a self-igniting propellant liquid phase ignition test system with variable environmental parameters, which, when working, comprises:

[0034] 1) Turn on the high-speed camera 9 and the light source 8, adjust the camera position, lens aperture size, light source intensity and position, so that the culture dish 5 is clearly located in the center of the field of view; calibrate the correspondence between the image pixels and the actual length.

[0035] 2) Open the upper cover of the stainless steel box 12, place the culture dish 5 on the liftable stage 6, and adjust the lift to a specified height; cover the upper cover and secure it with a quick clip.

[0036] 3) Open the exhaust port 2 valve, turn on the fan 10, and enter the specified gas atmosphere (such as nitrogen) for scavenging by controlling the air inlet 1 valve; monitor the target component concentration (such as oxygen concentration) through the gas component monitor 7, and when the gas component in the box reaches the specified concentration, close the exhaust port 2 valve, the air inlet 1 valve and the fan 10.

[0037] 4) Use a glass syringe to extract a specified amount of oxidant / fuel, connect a stainless steel needle to the syringe, and inject the oxidant / fuel into the culture dish 5 through the injection hole on the upper part of the stainless steel box 12.

[0038] 5) Install and fix the droplet generator 4.

[0039] 6) Open the valve of air inlet 1 and continue to introduce the specified atmosphere gas until the pressure inside the box reaches the specified pressure as monitored by pressure gauge 11, and then close the valve of air inlet 1.

[0040] 7) Trigger the droplet generator 4 to generate droplets, and use a high-speed camera 9 to capture the entire process of the droplets colliding with the liquid pool and igniting.

[0041] Process the obtained droplet impact pool ignition image:

[0042] 1) Read the pixel value of the droplet diameter from the image and determine the droplet diameter by the pixel size calibrated before the experiment.

[0043] 2) Read the displacement of the droplet in the 2-10 frames of pictures before the droplet hits the liquid pool, divide it by the time interval of the 2-10 frames of pictures, and obtain the velocity of the droplet when it hits the pool.

[0044] 3) The moment when the droplet hits the pool is defined as time zero, the moment when the flame appears in the picture is defined as the ignition moment, and the time interval between the two is defined as the ignition delay time.

[0045] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0046] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A hypergolic propellant liquid phase ignition test system with variable environmental parameters, characterized in that: It includes a device body, a droplet generator and a high-speed imaging system; The main body of the device is a stainless steel box, and two glass windows are provided at the bottom of the stainless steel box for visually photographing the ignition process of the internal droplets; the stainless steel box is an openable movable end cover, and a liquid injection hole is provided on the movable end cover for installing the droplet generator; An air inlet and an exhaust port are respectively installed on two opposite side walls of the stainless steel box; a liftable loading platform is arranged at the bottom of the stainless steel box, and a culture dish is arranged on the liftable loading platform; a gas component monitor is arranged outside the stainless steel box to monitor the gas components in the stainless steel box; The high-speed imaging system is used to collect images during testing in real time through the glass window.

2. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: An O-ring is provided between the movable end cover and the upper end surface of the stainless steel box body for sealing.

3. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: The movable end cover is fixed to the stainless steel box body by quick clamps.

4. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: The droplet generator and the movable end cover are sealed by an O-ring.

5. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: The droplet generator is fixed to the movable end cover by bolts.

6. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: The gas component monitor comprises a gas component content sensor arranged in a stainless steel box body, and an external monitor arranged outside the stainless steel box body, and the gas component content sensor is connected to the external monitor.

7. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: Both the air inlet and the air outlet are provided with valves.

8. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: A pressure gauge is also provided on the side wall of the stainless steel box.

9. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: A fan is also arranged on the side wall of the stainless steel box.

10. The hypergolic propellant liquid phase ignition test system with variable environmental parameters according to claim 1, characterized in that: The high-speed imaging system includes a high-speed camera, a zoom lens / telephoto microscope lens and a light source; the light source is used to emit scattered light to illuminate the target object, and the high-speed camera obtains the target object information through the zoom lens / telephoto microscope lens to form a video file, which can be viewed through a computer.

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