Transient plasma thermometer is a high-precision instrument designed based on optical principles, mainly used for transient high-temperature measurement under dynamic loads, such as detonation shock wave temperature, combustion temperature, and material impact temperature. The following are its standardized usage process and key technical points:
1、 Preliminary preparation and equipment inspection
-Confirmation of environmental adaptability
-Ensure that the laboratory temperature (-10~50 ℃) and humidity (≤ 95% non condensing) meet the instrument requirements, and avoid fluctuations in optical component performance caused by special environments.
-Check the stability of the power supply voltage and ensure that the grounding device is reliable to prevent electromagnetic interference.
-Hardware integrity check
-Verify that there is no physical damage to the components such as the host, fiber optic, photodetector, and data acquisition system, with particular attention to whether the fiber optic interface is clean and dust-free.
-Confirm that the high-speed data acquisition card with six or more channels has been correctly installed with drivers and has established a stable connection with the computer.
2、 Core operating procedures
-Optical system debugging
-Adjust the telescope optical system using the built-in laser calibration module to ensure that the optical path is aligned with the center area of the plasma.
-Activate the grating spectroscopic system and tune the wavelength to six narrowband filters within the range of 0.4-1.8 μ m, covering typical plasma emission spectral lines.
-Dynamic range optimization
-Automatically or manually set the integration time based on the estimated temperature range (1000~8000 ℃) to balance the signal-to-noise ratio and saturation risk.
-Activate the adaptive gain control function to prevent strong radiation signals from exceeding the linear response zone of the detector.
-Transient capture mode configuration
-Select the "rising edge" mode in the trigger menu, and set the threshold to three times the background noise level to accurately capture sudden plasma events.
-Enable the pre recording function of the circular buffer, retain the data stream of the first 5ms before triggering, and avoid missing the initial burst phase
3、 Data collection and real-time monitoring
-Multi dimensional parameter recording
Synchronize monitoring of the following key indicators:
-Timestamp (accuracy ± 1ns);
-Spectral intensity of each channel;
-Compensation coefficient for environmental temperature and humidity.
-Application of Visual Diagnostic Interface
-Real time observation of the evolution trend of characteristic peaks such as Ar I (750.4nm) and H α (656.3nm) through three-dimensional energy spectrum.
-Use the cursor tool to capture the complete radiation profile within a specific time period for subsequent Boltzmann slope method calculations.
4、 Data Processing and Analysis
-Dual temperature inversion algorithm
-Call the professional software package to perform the following steps:
① Perform least squares fitting on the four channel data and construct a Boltzmann line to determine the excitation temperature;
② Derive a radiation temperature model based on Planck's blackbody radiation law, and achieve dual temperature parameters obtained from a single measurement.
-Error correction strategy
-Introducing standard temperature lamps for spectral response coefficient calibration to eliminate system errors caused by detector sensitivity drift.
-Using the sliding average filtering algorithm to remove high-frequency noise and preserve effective signal components.
5、 Daily maintenance and quality control
-Periodic performance verification
-Use a standard light source with known temperature for monthly machine calibration to ensure that the error within the full range is less than 2%.
-Regularly replace desiccants to maintain a low humidity environment in the optical chamber.
The operation of this instrument must strictly follow relevant technical specifications such as GB/T 31265-2014, and optimize parameter combinations based on specific experimental requirements. For measurement tasks under complex working conditions, it is recommended to use cross validation to compare the consistency of results with other temperature measurement methods.