A rapid system identification method for measuring explosion heat by the constant temperature method

Abstract

In order to reduce the risk of measurement failure caused by system failure in the classical constant temperature method for measuring explosion heat, a measurement method was developed for identifying the explosion heat value based on the water temperature rise curve of an inner barrel before failure. Firstly, the heat transfer mechanism of the measurement process was analyzed, and the heat transfer model of the calorimeter was established, and the water temperature rise curve of the inner barrel in each measurement stage was obtained. Then, based on the system identification theory, the identification algorithm of intermediate parameters was proposed, and based on the idea of isolating easily oscillating parameters, a fast system identification algorithm was given to correct the temperature rise and explosion heat. And it is proved that the identification value of explosion heat approximately converges to the classical value. Finally, the test data of 8 explosive samples with explosion heat values ranging from 4 to 9 kJ/g were used to test the algorithm, and the test criterion for judging the convergence time was put forward. The simulation results show that the identification algorithm can effectively isolate the influence of the oscillation parameters and has a strong prediction ability on the temperature change of the water in the inner barrel, and that the identification value of explosion heat can quickly and stably converge to the upper limit of relative error of 3.5% within 40 min (1/3 of the main end stage), and that the test criterion can accurately judge the convergence time of the identified value of explosion heat. This method can also be extended to the adiabatic method for calculating explosion heat.