Research On Technology Of Near-ground Static Explosion Blast Wave Field Reconstruction

The various overpressure parameters of the explosion blast wave are important basis for evaluating the damage effectiveness of the warhead.Based on the blast wave overpressure information collected in the explosion test,mastering the pressure distribution in the blast wave field is of great value to the development and damage assessment of weapons in the military field.However,the number of blast wave data acquisition devices in the actual explosion test is limited.Considering the damage of the device during the test process and the large error of the separate spot data,the effective overpressure data volume becomes less,and it is difficult to comprehensively understand the blast wave field information depending on these data.For this situation,it is necessary to reconstruct the pressure distribution in the blast wave field based on the finite spots.Firstly,the drawbacks of the traditional overpressure storage test device were improved,and the blast wave storage test device with multiple trigger storage and time-base unification was introduced.Secondly,the cubic spline interpolation algorithm,Biharmonic spline surface interpolation algorithm and radial basis network interpolation algorithm are applied to the reconstruction of the near-ground static explosion blast wave overpressure peak.The comparison showed that the Biharmonic spline surface interpolation algorithm is more suitable for actual test where the spots are less and the spots’ distribution is discrete.The blast wave attenuation law constraint was added to the Biharmonic spline surface interpolation algorithm,assisting the algorithm to converge at the interpolation point and improving the peak reconstruction accuracy.The peak reconstruction of the measured data showed that the average error of the improved algorithm is less than 13%,which has certain practicability.Finally,the pressure distribution reconstruction of the positive pressure region behind the wavefront during the near-ground static explosion blast wave propagation was studied.Firstly,the blast wave overpressure-time curves of each spot were constructed,and the pressure distribution of the annular positive pressure zone behind the wavefront when wavefront propagates to different time was obtained.The Biharmonic spline surface interpolation algorithm was used in reconstruction of pressure distribution,the particle swarm optimization algorithm was used to search the distribution method with the best reconstruction accuracy,and the maximum reconstruction error is less than 11.41%.According to the measured data,the parameters were continuously corrected and the Ansys simulation was performed until the simulation point data was consistent with the corresponding measured data.It can be considered that the data of other simulation points were also in accordance with the actual measurement situation,and the simulation data was used to verify the optimal measurement point distribution.It showed that the maximum error of reconstruction is less than 13%,so this method provides a new idea for pressure distribution reconstruction and measuring point layout during actual measurement.