阅读说明：本技术 一种在极端条件下燃料氧化分解特性的测试装置 (Testing device for fuel oxidative decomposition characteristics under extreme conditions ) 是由 朱磊 李昂 张真英男 于 2020-05-08 设计创作，主要内容包括：本发明公开了一种在极端条件下燃料氧化分解特性的测试装置,包括混合腔,混合腔的进口端分别连接有高压液相进样泵和气瓶,混合腔出口端连接电阻炉进口端,电阻炉的出口端连接除水器；除水器再分别连接有气相色谱仪和排放测试仪,气相色谱仪和排放测试仪都连接到电脑；设置有压力稳定器,压力稳定器通过控制电阻炉的进气流量和排气流量调控压力；电阻炉和混合腔外部包裹有加热套；电阻炉的炉管外壁为不锈钢管,炉管内为一根石英管,石英管的外径与不锈钢管的内径相同。本发明装置便于在常压乃至高压条件下对燃料反应过程的中间组分进行测量,可靠性高,实时性好,能够满足实验所需精度。(The invention discloses a testing device for fuel oxidative decomposition characteristics under extreme conditions, which comprises a mixing cavity, wherein the inlet end of the mixing cavity is respectively connected with a high-pressure liquid-phase sample injection pump and a gas cylinder, the outlet end of the mixing cavity is connected with the inlet end of a resistance furnace, and the outlet end of the resistance furnace is connected with a dehydrator; the dehydrator is respectively connected with a gas chromatograph and an emission tester, and the gas chromatograph and the emission tester are both connected to a computer; the pressure stabilizer is arranged and used for regulating and controlling the pressure by controlling the air inlet flow and the exhaust flow of the resistance furnace; heating sleeves are wrapped outside the resistance furnace and the mixing cavity; the outer wall of a furnace tube of the resistance furnace is a stainless steel tube, a quartz tube is arranged in the furnace tube, and the outer diameter of the quartz tube is the same as the inner diameter of the stainless steel tube. The device provided by the invention is convenient for measuring the intermediate components in the fuel reaction process under normal pressure and even high pressure, has high reliability and good real-time property, and can meet the precision required by experiments.)

1. A testing device for fuel oxidative decomposition characteristics under extreme conditions is characterized by comprising a high-pressure liquid-phase sample injection pump (1), a mixing cavity (2), a resistance furnace (3), a dehydrator (4), a gas chromatograph (5), an emission tester (6), a computer (7), a pressure stabilizer (8), a mass flow meter (9) and a gas cylinder (10);

the inlet end of the mixing cavity (2) is respectively connected with a high-pressure liquid-phase sample injection pump (1) and a gas cylinder (10), the outlet end of the mixing cavity (2) is connected with the inlet end of a resistance furnace (3), and the outlet end of the resistance furnace (3) is connected with a dehydrator (4); the dehydrator (4) is respectively connected with a gas chromatograph (5) and an emission tester (6), and the gas chromatograph (5) and the emission tester (6) are both connected to a computer (7);

a pressure stabilizer (8) is arranged, and the pressure stabilizer (8) regulates and controls the pressure by controlling the air inlet flow and the exhaust flow of the resistance furnace (3); heating sleeves are wrapped outside the resistance furnace (3) and the mixing cavity (2); the outer wall of the furnace tube of the resistance furnace (3) is a stainless steel tube, a quartz tube is arranged in the furnace tube, and the outer diameter of the quartz tube is the same as the inner diameter of the stainless steel tube.

2. A device for testing the oxidative degradation of fuels under extreme conditions, according to claim 1, characterized in that a mass flow meter (9) is also connected between the cylinder (10) and the mixing chamber (2).

3. A test device of fuel oxidative decomposition characteristics under extreme conditions according to claim 1, wherein the pressure stabilizer (8) has an exhaust gas mass flow meter (24), an intake gas mass flow meter (25), a control circuit board (26), and a pressure sensor (27); the air inlet mass flowmeter (25) and the exhaust mass flowmeter (24) are both high-pressure-resistant mass flowmeters; when the gas flow control device works, the gas flow passing through the gas inlet mass flow meter (25) is manually set according to experiment requirements, the gas flow enters the furnace tube through the outlet of the gas inlet mass flow meter (25), the pressure sensor (27) inserted into the furnace tube can monitor the pressure in the furnace tube in real time and feed back the pressure to the control circuit board (26), and the control circuit board (26) dynamically adjusts the exhaust flow of the exhaust mass flow meter (24) according to the pressure set value required by the experiment and in combination with the feedback signal of the pressure sensor (27).

Technical Field

The invention relates to the field of fuel combustion characteristic testing, in particular to a testing device for fuel oxidative decomposition characteristics under extreme conditions.

Background

With the increasing awareness of energy crisis and human environment, especially the control of the pollution emission (NOx, greenhouse gas CO2, etc.) of internal combustion engines is becoming stricter, and with the proposal of country vi, various departments have strengthened the research on the aspects of the improvement of the efficiency of internal combustion engines, the reduction of the pollution emission, etc. Among them, increasing the combustion efficiency of conventional fossil energy and novel renewable energy and reducing the emission of pollutants have been receiving much attention. There has been a great deal of research in the field of combustion from small hydrocarbon CH4 (the main component of natural gas) to large hydrocarbon fuels such as gasoline, diesel, etc. BP energy 2019 yearbook that global demand for two traditional fossil energy sources, oil and gas, is still increasing year by year in the next 20 years. The occupation ratio of novel renewable energy sources such as biomass is also gradually increased. Combustion will be one of the most important means of providing energy to society for some time in the future, and also for the transportation industry, so the research on the combustion characteristics of energy is of great importance. By researching the reaction kinetics of the fuel, a series of reaction kinetics models can be further developed, the models can predict the combustion characteristics of different fuels under different working conditions through numerical simulation, and further provide guidance for the improvement of the engine combustion technology, the development of new low-carbon fuels and the like so as to reduce the experiment cost.

In order to develop a dynamic model for a corresponding fuel, many different kinds of experimental devices have been invented so far. Such as constant volume bumers, flash compressors, shock tubes, jet stirred reactors, flow reactors, and the like. Each of these devices has its own strengths and weaknesses. For the developed reaction kinetics model, in order to expand the application range of the model, a large amount of experimental data needs to be used for correcting the model, so that data points are required to be abundant and a larger working condition range is required to be covered. Existing experimental equipment such as rapid compressors and shock tubes can measure the ignition delay time of fuel under variable pressure, and the available experimental bench is rare when the intermediate components and the concentration of the fuel in the reaction process need to be measured.

Disclosure of Invention

The invention aims to provide a device for testing the oxidative decomposition characteristic of fuel under extreme conditions, which is convenient for measuring intermediate components in the fuel reaction process under normal pressure or even high pressure.

In order to solve the technical problems, the invention adopts the technical scheme that:

a testing device for fuel oxidative decomposition characteristics under extreme conditions comprises a high-pressure liquid-phase sample injection pump, a mixing cavity, a resistance furnace, a dehydrator, a gas chromatograph, an emission tester, a computer, a pressure stabilizer, a mass flowmeter and a gas cylinder;

the inlet end of the mixing cavity is respectively connected with a high-pressure liquid-phase sample injection pump and an air bottle, the outlet end of the mixing cavity is connected with the inlet end of a resistance furnace, and the outlet end of the resistance furnace is connected with a dehydrator; the dehydrator is respectively connected with a gas chromatograph and an emission tester, and the gas chromatograph and the emission tester are both connected to a computer;

the pressure stabilizer is arranged and used for regulating and controlling the pressure by controlling the air inlet flow and the exhaust flow of the resistance furnace; heating sleeves are wrapped outside the resistance furnace and the mixing cavity; the outer wall of a furnace tube of the resistance furnace is a stainless steel tube, a quartz tube is arranged in the furnace tube, and the outer diameter of the quartz tube is the same as the inner diameter of the stainless steel tube.

Further, a mass flow meter is connected between the gas cylinder and the mixing cavity.

Further, the pressure stabilizer has an exhaust mass flow meter, an intake mass flow meter, a control circuit board, and a pressure sensor; the intake mass flowmeter and the exhaust mass flowmeter both adopt high-pressure-resistant mass flowmeters; when the gas flow meter works, the gas flow flowing through the gas inlet mass flow meter is manually set according to experiment requirements, the gas flow enters the furnace tube through the outlet of the gas inlet mass flow meter, the pressure sensor inserted into the furnace tube can monitor the pressure in the furnace tube in real time and feed back the pressure to the control circuit board, and the control circuit board dynamically adjusts the exhaust flow of the exhaust mass flow meter according to the pressure set value required by the experiment and the feedback signal of the pressure sensor.

Compared with the prior art, the invention has the beneficial effects that:

1) through the combination of the high-pressure sample introduction device, the pressure stabilizing device, the high-pressure resistant reaction device and the detection device, the research on the fuel oxidative decomposition characteristic under the extreme working condition which cannot be realized by a conventional rack is realized. The invention can be used for researching fuel in the pressure range of 1-100bar and the temperature range of not more than 1300K.

2) For other devices capable of researching the fuel oxidative decomposition characteristics under high pressure, the design of the reaction section of the high-pressure furnace tube is simpler, the quartz tube is prevented from being burst due to unbalanced pressure by using the stainless steel tube with the inner diameter matched with the outer diameter of the quartz tube, and a complex quartz tube air pressure balancing device is omitted, so that the overall reliability of the system is obviously improved, and the required precision of an experiment can be met.

3) By additionally arranging the California emission instrument in the detection system, the concentration of certain components in the exhaust gas can be monitored in real time, so that the real-time performance of detection is improved, and the uncertainty caused by the fact that the stabilization time is judged only by experience under a high-pressure working condition and the time waste caused by the fact that the gas chromatograph is frequently used for detecting products to judge balance are avoided. For different working conditions and different fuels, the method has more obvious advantage in the aspect of judging the real-time property of the reaction equilibrium time.

Drawings

FIG. 1 is a schematic diagram of the overall structure of a fuel oxidative decomposition characteristic testing device under extreme conditions according to the present invention.

FIG. 2 is a schematic diagram of a high-pressure liquid-phase sample injection pump in the device of the present invention.

FIG. 3 is an internal view of the high pressure liquid phase sample injection pump of the present invention.

Fig. 4 is a schematic view of the pressure stabilizer structure of the device of the present invention.

In the figure: a high-pressure liquid-phase sample injection pump 1; a mixing chamber 2; a resistance furnace 3; a dehydrator 4; a gas chromatograph 5; an emission tester 6; a computer 7; a pressure stabilizer 8; a mass flow meter 9; a gas cylinder 10; a pump head 11; an in-line filter 12; a peristaltic pump 3; an inlet check valve 14; a bypass valve knob 15; a bypass vent valve 16; a stepping motor 17; a main cam 18; the sub-cam 19; a sub-plunger pump 20; an outlet check valve 21; a main plunger pump 22; an inlet check valve 23; an exhaust gas mass flow meter 24; an intake mass flow meter 25; a control circuit board 26; a pressure sensor 27.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

As shown in fig. 1, the device of the invention comprises three systems, namely a sample introduction system, a reaction system and a detection system, wherein the sample introduction system comprises a component high-pressure liquid phase sample introduction pump 1, a mixing cavity 2, a mass flow meter 9 and a gas cylinder 10; the reaction system comprises a component resistance furnace 3, a dehydrator 4 and a pressure stabilizer 8; the detection system comprises a component gas chromatograph 5, an emission tester 6 and a computer 7. The inlet end of the mixing cavity 2 is respectively connected with a high-pressure liquid-phase sample injection pump 1 and a gas cylinder 10, the outlet end of the mixing cavity 2 is connected with the inlet end of a resistance furnace 3, and the outlet end of the resistance furnace 3 is connected with a dehydrator 4; the dehydrator 4 is respectively connected with a gas chromatograph 5 and an emission tester 6, and the gas chromatograph 5 and the emission tester 6 are both connected to a computer 7; a pressure stabilizer 8 is arranged, and the pressure stabilizer 8 regulates and controls the pressure by controlling the air inlet flow and the exhaust flow of the resistance furnace 3; heating sleeves are wrapped outside the resistance furnace 3 and the mixing cavity 2; the outer wall of the furnace tube of the resistance furnace 3 is a stainless steel tube, a quartz tube is arranged in the furnace tube, and the outer diameter of the quartz tube is the same as the inner diameter of the stainless steel tube.

Before the experiment begins, the heating jackets wrapped outside the resistance furnace 3 and the mixing cavity 2 can be preheated, meanwhile, the gas cylinder 10 provides a gas flow to provide pressure for the furnace tube in the resistance furnace 3, the pressure in the furnace tube is adjusted and maintained by the pressure stabilizer 8, and the pressure stabilizer 8 mainly realizes the regulation and control of the pressure by controlling the air inlet flow and the air exhaust flow. Liquid fuel that awaits measuring will go into mixing chamber 2 through high-pressure liquid phase sampling pump 1, and mass flow meter 9 can inject mixing chamber 2 with the gas in the gas cylinder 10 quantitatively simultaneously, and liquid fuel is heated gasification and takes place to mix with the gas that comes from gas cylinder 10 in mixing chamber 2, and the gas of misce bene can get into the stove intraductal further heating of resistance furnace 3 and then take place chemical reaction. The outer wall of the furnace tube of the resistance furnace 3 is a stainless steel tube which can bear the internal gas pressure, a quartz tube is arranged in the furnace tube, and the mixed gas flows in the quartz tube and carries out chemical reaction, so that the potential influence of the stainless steel tube on the reaction of the mixed gas is avoided. The outer diameter of the quartz tube is the same as the inner diameter of the stainless steel tube, so that the quartz tube can be prevented from being cracked under high pressure. The gas after the reaction can remove water generated in the reaction process through the dehydrator 4, so that the influence of condensed water on a detection device and a pressure stabilizer can be avoided, and reactants after dehydration are introduced into the gas chromatograph 5 and the discharge tester 6. The emission tester 6 can detect the concentrations of oxygen, carbon monoxide and carbon dioxide in the exhaust gas in real time, the concentrations of the reactants can be used as a criterion for the exhaust gas at the tail end of the furnace tube to reach a stable state, components in the exhaust gas and the concentrations of corresponding components can be measured by the gas chromatograph 5 after the reaction reaches the stable state, and the measurement result can be fed back to the computer 7. Through the serial use of the three systems, a practical and effective technical mode for researching the oxidative decomposition characteristics of the substances under extreme conditions can be obtained.

For a system capable of conducting fuel oxidative decomposition characteristic studies at high pressure, the components within the device need to be customized to meet the requirements for proper operation at high pressure, which presents higher requirements and difficulties than conventional laboratory benches.

For the existing conventional experiment bench, the sample feeding device usually consists of a micro-injection pump (consisting of a pump body and a syringe), a gas cylinder and a common mass flowmeter without pressure resistance requirement. For the sample injection system of the device, in order to stably and uniformly inject fuel into the reaction furnace under the condition of high back pressure, a sample injection pump which is more complicated than a conventional rack and a mass flow meter which can resist high pressure need to be used. The structure of the high-pressure liquid phase sample injection pump 1 used by the device is shown in figures 2 and 3. In order to meet the high-pressure sample feeding requirement, the high-pressure liquid-phase sample feeding pump 1 adopts the design of a main plunger pump 22 and an auxiliary plunger pump 20, the main plunger pump 22 and the auxiliary plunger pump 20 are driven by the same stepping motor 17, and the plunger motion phases of the two plunger pumps are opposite. When the plunger head of the main pump moves backwards, vacuum is formed in the plunger cavity, so that liquid fuel can be sucked into the cavity of the main plunger pump 22 firstly, and meanwhile, the design of the inlet check valve 23 can prevent the fuel sucked into the plunger pump from flowing back to a fuel bottle under high pressure. And then, the plunger head of the main pump moves forwards, the plunger head of the auxiliary pump moves backwards at the moment, the fuel in the plunger cavity of the main pump is sucked into the plunger cavity of the auxiliary pump, and therefore the fuel circulates and reciprocates, reaches the auxiliary pump through the main pump, and is pumped into the high-pressure mixing cavity finally.

In order to provide back pressure and adjust the pressure in the furnace tube in real time to keep the pressure constant, compared with the conventional rack, the invention is additionally provided with a pressure stabilizer 8, and the core components in the pressure stabilizer 8 are shown in FIG. 4 and comprise an exhaust mass flowmeter 24, an inlet mass flowmeter 25, a control circuit board 26 and a pressure sensor 27. The intake mass flow meter 25 and the exhaust mass flow meter 24 are high-pressure-resistant mass flow meters, and both can withstand 100bar air pressure in the present invention. When the gas-liquid separation device works, the flow rate of gas flowing through the gas inlet mass flowmeter 25 can be manually set according to experimental requirements, the gas flow enters the furnace tube through the outlet of the gas inlet mass flowmeter 25, the pressure sensor 27 inserted into the furnace tube can monitor the pressure in the furnace tube in real time and feed back the pressure to the control circuit board 26, the control circuit board 26 automatically and dynamically adjusts the exhaust flow rate of the exhaust flowmeter 24 according to the pressure set value required by the experiment and the feedback signal of the pressure sensor 27, and finally the pressure in the furnace tube can be basically constant.