Data for the proportion of longitudinal stress travelling in Modes 1-4 in a Hopkinson pressure bar, for 0.35 < fa/c0 < 0.90, at the bar surface and as a cross-sectional mean

This dataset contains tabulated values for how the stress in a high frequency waveform will be divided between each of the first four propagating modes, for longitudinal waves in cylindrical pressure bars, up to a normalised frequency of fa/c0=0.9. This data can be used to perform four-mode dispersion correction of high frequency signals, such as overpressure measurements from blast loading using Hopkinson pressure bars.Data was calculated using LS-DYNA to model the propagation of single-frequency pulses in a long steel pressure bar. At each normalised frequency a short, raised-cosine windowed sinusoidal forcing function was applied to the end of the bar. The stress in the bar dispersed into multiple modal 'pulses' as it propagated, allowing the contribution of each mode to be calculated from the amplitude of the pulses.Values are provided up to a normalised frequency of fa/c0 = 0.9, where f is frequency, a is the radius of the bar, and c0 is the one-dimensional wave speed. The table indicates whether the values are modelled directly in LS-DYNA (M) or calculated by interpolation of the modelled results (I).More details are available in our Impact Engineering paper below:

本数据集包含高频波形中应力如何分配至前四种传播模式的表格化数值，适用于圆柱形压力杆中的纵向波，直至归一化频率fa/c0等于0.9。此数据可用于对高频信号进行四模式色散校正，例如使用霍普金森压力杆进行的爆加载过压测量。数据是通过LS-DYNA软件模拟单频脉冲在长钢压力杆中的传播过程而计算得出。在每一个归一化频率下，对杆端施加了短时上升余弦窗函数的正弦激励。随着波的传播，杆中的应力分散为多个模态脉冲，从而可根据脉冲幅度计算出每个模态的贡献。所提供的数据直至归一化频率fa/c0等于0.9，其中f为频率，a为杆的半径，c0为一维波速。表格指明了数值是直接在LS-DYNA中模拟得出的（M）还是通过模型结果的插值计算得出的（I）。更多详细信息可参阅以下《冲击工程》论文：