41 results about "Minimum ignition energy" patented technology

The invention relates to a method and a device for calibrating an eclectic arc discharge energy correction factor. A formula of eclectic arc discharge energy is given according to a semi-empirical formula of minimum ignition energy; energy generated in the electric arc discharge process is calculated according to a relation that the voltage and the current of a gas discharge electric arc change along with time, and finally, in combination with the temperate of the eclectic arc obtained by measurement, the arc length and the radius, the value of the correction factor in the formula is calibrated. The method comprises the following steps: (1) measuring the voltage and current information of the gas discharge electric arc; (2) obtaining the energy generated in the discharge process through an integral of a product of the voltage and the current on a time axis by adopting a mathematical method; (3) measuring the spectral information of the electric arc to obtain the temperature of the electric arc; (4) measuring the size information of the electric arc, wherein the size information comprises length and radius; (5) substituting into the calibration formula of the discharge energy E of the electric arc according to the energy obtained in the step (2), the temperature obtained in the step (3) and the size information obtained in the step (4) to obtain the value of the correction factor K1. The method provided by the invention is convenient to configure and flexible to operate and can quantifiably measure and calibrate the correction factor in the electric arc discharge energy formula.

The present invention relates to a minimum ignition energy test system and method for combustible gas explosion at ultra-low temperature. The test system includes a vacuum pumping system, a gas distribution system, a refrigeration system, an integral circuit ignition system and a data acquisition system. An explosion container is installed in the refrigeration system , the vacuum system communicates with the explosion vessel through the connecting pipeline of the gas distribution system, and the gas distribution system communicates with the interior of the explosion vessel through the connecting pipeline; the integral ignition system includes an ignition energy test bench, an ignition electrode located in the explosion vessel, a The probe and current transformer, the ignition energy test bench are connected to the ignition electrode, the high-voltage probe and the current transformer are respectively connected to the ignition energy test bench and the ignition electrode; the data acquisition system includes a data collector and is connected to the data collector and installed on Pressure sensor and temperature sensor inside the explosion vessel. The test system of the present invention has high safety performance and accurate test performance, and can accurately test the minimum ignition energy of combustible gas explosion at ultra-low temperature and high pressure, and the measured data is of great significance for guiding the safe production of the oxygen-containing coalbed methane liquefaction process.

The invention relates to a device and a method for testing the explosion properties of flammable gases at ultralow temperature. The device comprises a refrigerating device, an explosion vessel with a length-diameter ratio of 3 to 1 is arranged in an inner cavity of the refrigerating device, a gap is formed between the explosion vessel and the inner cavity of the refrigerating device, and a heat conducting material by which the temperatures of the explosion vessel and gas in the explosion vessel are reduced to an experimental temperature is added in the gap; the top of the explosion vessel is sealed by a blind flange, two ignition electrodes connected with an ignition energy console are arranged in the explosion vessel, the bottom of the explosion vessel is provided with a liquid outlet for implementing the cleaning of deposited carbon in the explosion vessel, and a strain gage for carrying out real-time monitoring on heat stress produced in the process of explosion is attached to the inner wall of the explosion vessel; and the blind flange is provided with a temperature sensor, a pressure sensor, a gas inlet and a gas outlet, and the gas inlet and the gas outlet are communicated with the inside of the explosion vessel. The device disclosed by the invention can be used for eliminating the trouble that the application amount of liquid nitrogen in liquid-nitrogen refrigerating is huge, and avoiding the occurrence of risks and ultra-high heat stress caused by the rapid evaporation of liquid nitrogen due to heat produced by explosion; and the device is high in refrigeration efficiency, and can meet the requirements on minimum ignition energy and explosion limit tests.

The invention discloses an intrinsically safe Buck converter parameter design method considering the temperature effect, including: given the inductor current ripple, output ripple voltage and minimum ignition energy of the Buck converter; Input voltage range, load range, operating temperature range, output voltage, operating frequency and the resistance value R of the equivalent series resistance C ; Calculate the minimum inductance and input voltage and R of the intrinsically safe Buck converter C The minimum value of capacitance within the dynamic range; calculate the capacity range of Buck converter capacitor C and the resistance range of equivalent series resistance within the operating temperature range; calculate the maximum short-circuit discharge energy and maximum output ripple voltage according to the above design parameters, and judge whether they meet Output intrinsically safe requirements, if satisfied, the design is complete; if not satisfied, it is necessary to reduce R C Or increase the working frequency and repeat the above steps until the requirements are met. The invention effectively improves the output intrinsic safety performance of the converter.

The invention relates to a method for testing the minimum ignition energy of a gas-solid two-phase combustible material, which mainly solves the problem that there is no minimum ignition energy test method for the gas-solid two-phase in the prior art. The present invention adopts a minimum ignition energy test method of gas-solid two-phase combustible materials, and adopts a minimum ignition energy testing device to test the minimum ignition energy of gas-solid two-phase combustible materials. The main body of the device is a spherical test chamber, a vacuum pump, a buffer The tank is connected to the cavity, and the ignition electrode is installed on the flange on the upper side of the cavity. The technical solution that one end of the precision spark generator is connected to the ignition electrode, and the other end is connected to the computer solves the above problems well, and can be used for gas In the test of the minimum ignition energy of solid two-phase combustible materials.

The invention relates to an intrinsic safety LED (Light Emitting Diode) driving power source with high power for mines and belongs to a driving power source for LED lamps. The intrinsic safety LED driving power source with high power comprises a high frequency flyback converter, a rectifying circuit, an output filtering circuit, a feedback circuit and a PWM (Pulse Width Modulation) controller, wherein an output end of the high frequency flyback converter is connected with the rectifying circuit; the output end of the rectifying circuit is connected with the output filtering circuit; the output end of the output filtering circuit is a circuit output end and simultaneously is connected with an input end of the feedback circuit; and the feedback circuit is connected with the high frequency flyback converter through the PWM controller. Compared with the prior art, the intrinsic safety LED driving power source has the advantages that the power source is always kept constant under the condition of changing a load or input voltage and output current, and when the short-circuiting happens in the output, the released energy is below the minimum ignition energy value of a gas, thereby the explosion is avoided; and the intrinsic safety LED driving power source has simple structure and long service life, is energy-saving and environment-friendly, is convenient to carry and is suitable for hazardous areas such as coal mines, petrochemical industries and the like.

The invention relates to a closed-loop control method of a low-voltage DC CDI (Loop locked CDI, LLCDI) igniter, comprising steps: 1: setting a two-point or multi-point boost detection circuit, that is, the lowest ignition energy voltage point and the highest limited voltage point; 2: Measure the time Td for boosting the voltage to the highest limit point voltage when powering on, and load the appropriate duty cycle parameters accordingly; 3: Measure the time Ea for the boost charging voltage from zero (after the last ignition trigger) to the lowest ignition energy voltage point Point time Tp, 4: compare the measured Tp with the set standard Ts, and adjust the duty cycle of the boost signal by one (or more) duty cycle steps accordingly; 5: trigger discharge , the boost circuit starts working again; iteratively execute steps 3, 4, and 5 until the adjusted boost curve coincides with the predetermined boost curve at the highest degree, and the error between Tp and Ts is the smallest. The present invention improves the integration and efficacy of the DC CDI igniter through the series of closed-loop control methods.

The invention discloses a method for analyzing the minimum ignition energy of combustible gas, which comprises steps 1, establishing a combustible gas minimum ignition energy model based on flame diffusion boundary layer theory; The critical flame radius in the gas minimum ignition energy model; 4. Analyze the critical flame layer number in the combustible gas minimum ignition energy model; 5. Obtain the calculation model of the combustible gas minimum ignition energy. The method of the invention has simple steps and reasonable design. Based on the flame diffusion boundary layer theory and the properties of the fuel itself, a calculation model for the minimum ignition energy is established in combination with physical and chemical foundations, which can effectively analyze the minimum ignition energy of the combustible gas, and analyze the effect of the model parameters on the minimum ignition energy of the combustible gas. The influence law of ignition energy, the analysis effect is remarkable, lays the foundation for the detection of gas combustion and explosion performance, and is easy to popularize.