Volume of detonation determination based on gaseous products of energetic materials by time resolved LIPS combined with schlieren image.

The safe and fast measurement of volume of detonation (VoD) is always a hard task for macroscale explosion even though it is one of the important parameters to evaluate the explosion performance. Therefore, a promising technology to determine the VoD is highly desirable for evaluation of energetic materials. Herein, a new method of VoD determination based on gaseous products via small dose energetic materials by time correlated laser induced plasma spectroscopy (LIPS) combined with schlieren image was proposed. Hydrodynamics of products after laser ablation on a time scale ranging from microsecond to millisecond was investigated. Based on the analysis of hydrodynamics of products after laser ablation, the effective spectra of gaseous products of each energetic material are obtained. Subsequently, a high-accuracy quantitative analysis model of VoD based on gaseous products using the method of principal component analysis - partial least squares (PCA-PLS) with small sample modeling algorithm has been developed( R>0.96). The VOD model accurately predicts the detonation parameters with the average relative error of test set (ARET) < 3% and the maximum relative error of test set (MRET) < 5%. Moreover, the results without spectra selection of the relative error of blind data show the max relative error is less than 7%. The results of variable importance in projection (VIP) identification indicate a robust association between the spectral signatures of carbon (C), nitrogen (N), hydrogen (H), oxygen (O) and VoD. Furthermore, the N lines exert the most substantial influence on the VoD model. This method provides a new safe and fast determination technology for the evaluation of VoD and clarification of the related mechanism.