If the location of peak overpressure front at time [t.sub.i] is given as [Z.sub.pi], then, the ground above the depth [Z.sub.pi] experiences compressive stresses lower than those caused by the peak overpressure front at that depth.
With increasing stress level, [V.sub.kz] decreases [17, 23]; hence, it is logical to assume that [f.sub.kz] increases with increasing stress level and the maximum value is attained at a peak stress level corresponding to the peak overpressure front.
where [P.sub.o] and [t.sub.eq] are peak overpressure and equivalent positive phase duration, respectively.
Peak overpressure will usually be different on each face of the building with the highest being on the face directly opposing the blast source.
Properly select the blast damper for the specific blast peak overpressure and impulse duration of the project.
Alai et al., "Rat injury model under controlled field-relevant primary blast conditions: acute response to a wide range of peak overpressures
," Journal of Neurotrauma, vol.
With reference to Figure 13, it was observed that in the simulation, the recorded peak over pressure is 12.7 MPa, while the field blast test result shows the peak overpressure
of 14.8 MPa.
Both types of exit boundary conditions produce the same peak overpressure strength, because the duct is long enough to develop a normal shock capable of yielding the same strength at the throat as a normal shock generated at the engine face.
A comparison between the 3-D CFD results to the existing F-16 characteristic overpressure ratio distribution shows that the peak inlet overpressure distribution is a collation of peak magnitudes of the hammer-shock waveform along the NSI duct, while the peak overpressure ratio is calculated at every station and normalized by the engine-face overpressure ratio.
The peak overpressure ratio inside the inlet occurred at the throat, similar to the previously mentioned historical trends.