| While more and more investigation focus on combustion process in internal combustion engine, it is required to set up fundamental chemical kinetics and ignition delay time database of hydrocarbon under various pressure and temperatures in this process. The research of ignition of hydrocarbon fuels can provide important theoretical support that the new combustion way, improved combustion chamber design, improving fuel thermal efficiency and reduce pollutant emissions.Shock tube is the experimental device that uses the principle of heating the material to achieve very high stagnation temperatures. We can easily adjust temperature, pressure and speed in a wide range by using the incident and reflected shock tube shock. Therefore, this paper designed and developed high-pressure shock tube used in chemical kinetics of combustion chemistry. Because of different choice of fire mark signals, the ignition delay data obtained are different. This choice OH radical emission intensity signal as a fire signal, by using of PMT. In this shock tube experiments, the ignition delay is defined as the reflected waves reach the measurement point pressure signal and the point appears the signal fire marked the time difference. Firstly, high-frequency ICPs record the incident/reflected shock pressure time signal. Then, by PMT signal-time curves recorded by the pressure and the emission intensity-time curve to determine the ignition delay.Ethanol and butanol as an alternative to conventional gasoline and diesel fuel have broad application prospects. But the research is far from meeting the needs of engineering, especially for operating conditions in a gasoline engine ignition delay is still quite a lack of basic data. Therefore, this chemical shock tube in the double membrane on the experimental device, driven by helium gas, the use of reflected shock wave, by measuring the OH* from the light signal, its signal peak slope at the beginning of a fire sign, is given the definition of ignition delay.The experiment of ethanol/nitrogen/oxygen mixture in the temperature range of 1094.86-1280.72K, the pressure range of 0.628-0.732MPa , when the ratio of the ignition delay for the 0.8,1.0,1.2 was carried out. Then the experiment of butanol/nitrogen/oxygen mixture in the temperature range of 1043.32-1163.72K, the pressure range of 0.671-0.835MPa, when the ratio of the ignition delay for the 0.5,1.0,1.5 was carried out. The main conclusions obtained are as follows: (1) With increasing temperature, the ignition delay of the mixture decrease, ignition delay and the logarithm of the reciprocal of temperature is proportional to meet the Arrhenius relationship.(2) As the gas mixture fuel concentration increases, per unit volume of fuel molecules to participate in response to increased number of collisions in chemical reactions more effectively, the reaction rate accelerated. Thus, with the equivalence ratio increased, the ignition delay decreases.(3) According to Arrhenius relationship, the ratio is 1 when fitting the mixed gas to get ethanol/nitrogen/oxygen mixtureτig and T, p of the relationship? ig ?2. 549p(?2.012)exp?5 866/T?, reflecting the dependence of ignition delay on the high pressure, and activation energy When the ratio changes are not sensitive.(4) According to Arrhenius relationship, the ratio is 1 when fitting the mixed gas to get butanol/nitrogen/oxygen mixtureτig and T, p of the relationship? ig ?1. 14p(?4.1476)exp?4 795/T?, reflecting the dependence of ignition delay on the high pressure, and activation energy when the ratio changes are not sensitive.(5) Mixture ignition delay measurements, the main deviation includes: ignition temperature T5 of the measured or calculated ignition delayτig measurement deviation. The main reason: shock attenuation, real gas effects, boundary layer effects, vibration relaxation, the ignition acceleration, shock fork and other factors.
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