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Space launch vehicles are usually loaded with a large amount of propellant, and the destructive power caused by their explosion is significant. The altitude of an accidental explosion will lead to differences in the destructive power, because the environmental parameters of different altitudes are different, and the explosion shock wave parameters are closely related to the environmental parameters. Therefore, it was necessary to establish a set of analytical methods to rapidly analyze the relationship between altitude and the explosion shock wave parameters. A large number of simulation conditions were tested at 0~10 km altitude using the nonlinear dynamics software AUTODYN. The relationship between the explosion shock wave pressure P, the proportional distance z, and the altitude h was obtained, which could be used to rapidly characterize the explosion shock wave pressures at different altitudes. A comparative analysis was conducted with the experimental results to verify the scientificity of the fitting formula. The results indicate that the error between the experimental and calculated values is less than 5.80%, indicating that the rapid evaluation formula established in this paper is reasonable. These findings not only enrich the theory related to explosion shock waves, but also provide a rapid analysis basis for the accidental explosion of space launch vehicles. [ABSTRACT FROM AUTHOR]

Space launch vehicles are usually loaded with a large amount of propellant, and the destructive power caused by their explosion is significant. The altitude of an accidental explosion will lead to differences in the destructive power, because the environmental parameters of different altitudes are different, and the explosion shock wave parameters are closely related to the environmental parameters. Therefore, it was necessary to establish a set of analytical methods to rapidly analyze the relationship between altitude and the explosion shock wave parameters. A large number of simulation conditions were tested at 0~10 km altitude using the nonlinear dynamics software AUTODYN. The relationship between the explosion shock wave pressure P, the proportional distance z, and the altitude h was obtained, which could be used to rapidly characterize the explosion shock wave pressures at different altitudes. A comparative analysis was conducted with the experimental results to verify the scientificity of the fitting formula. The results indicate that the error between the experimental and calculated values is less than 5.80%, indicating that the rapid evaluation formula established in this paper is reasonable. These findings not only enrich the theory related to explosion shock waves, but also provide a rapid analysis basis for the accidental explosion of space launch vehicles.

A method for finding out the analytical expressions of pressure and the time of shock wave positive phase during underwater explosion has been defined as a function of explosive weight and the distance from the explosion center. The methods of mathematical statistics have been applied to define the method of finding out the model of parameters of pressure momentum of underwater explosion shock waves. The analytical expressions of partial correlation coefficients and the multiple correlation coefficient have been defined for the qualitative evaluation of obtained models accordance with experimental data.

Detonation of a high-explosive produces shock-blast wave, shrapnel, and gaseous products. While direct exposure to blast is a concern near the epicenter, shock-blast can affect subjects, even at farther distances.When a pure shock-blast wave encounters the subject, in the absence of shrapnels, fall, or gaseous products the loading is termed as primary blast loading and is the subject of this paper. The wave profile is characterized by blast overpressure, positive time duration, and impulse and called herein as shock-blast wave parameters (SWPs). These parameters in turn are uniquely determined by the strength of high explosive and the distance of the human subjects from the epicenter. The shape and magnitude of the profile determine the severity of injury to the subjects. As shown in some of our recent works (1-3), the profile not only determines the survival of the subjects (e.g., animals) but also the acute and chronic biomechanical injuries along with the following biochemical sequelae. It is extremely important to carefully design and operate the shock tube to produce field-relevant SWPs. Furthermore, it is vital to identify and eliminate the artifacts that are inadvertently introduced in the shock-blast profile that may affect the results. In this work, we examine the relationship between shock tube adjustable parameters (SAPs) and SWPs that can be used to control the blast profile; the results can be easily applied to many of the laboratory shock tubes. Further, replication of shock profile (magnitude and shape) can be related to field explosions and can be a standard in comparing results across different laboratories. Forty experiments are carried out by judiciously varying SAPs such as membrane thickness, breech length (66.68-1209.68 mm), measurement location, and type of driver gas (nitrogen, helium). The effects SAPs have on the resulting shock-blast profiles are shown. Also, the shock-blast profiles of aTNT explosion from ConWep software is compared with the profiles obtained from the shock tube. To conclude, our experimental results demonstrate that a compressed-gas shock tube when designed and operated carefully can replicate the blast time profiles of field explosions accurately. Such a faithful replication is an essential first step when studying the effects of blast induced neurotrauma using animal models. [ABSTRACT FROM AUTHOR]