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将非傅里叶耦合热弹性方程无量纲化得到了通用的表征热力耦合效应的无量纲数λ;通过分析比较无量纲非傅里叶耦合与非耦合热弹性方程的级数解,研究了短脉冲激光辐照的非傅里叶热力耦合效应的特性。发现热力耦合不仅使光致热应力波较非耦合的波速增大,波长变长,波幅在传播过程中不断衰减,并使该应力波激发出与其速度相同的第二温度波。不论耦合与非耦合,应力波随参数ε的变化均具有饱和特性且在某一条件下呈现奇异的双峰波形。热力耦合效应的强弱主要取决于λ;另外还取决于脉冲触发后经历的时间和脉冲底宽之比,比值越大,耦合效应越强。因而对于超短脉冲激光辐照情况,在通常λ的绝对值较小(10~(-3)量级及以下)的情况下,忽略热力耦合效应也可能会导致较大误差。
The dimensionless number λ, which characterizes the thermodynamic coupling effect, is obtained by dimensionlessization of non-Fourier coupled thermoelasticity equations. By analyzing and comparing the series solutions of thermodynamics and non-Fourier non-Fourier coupling, Characteristics of Nonthermonic Coupling Effect of Pulsed Laser Irradiation. It is found that the thermal coupling not only increases the wave speed of photoinduced thermal stress more than the uncoupled wave, but also decreases the amplitude of the wave in the propagation process. As a result, the stress wave excites the second temperature wave with the same speed. Both the coupling and the non-coupling stress wave have the characteristics of saturation with the change of the parameter ε, and the singular bimodal waveform appears under certain conditions. The strength of the thermal coupling depends mainly on λ; it depends on the ratio of the duration of the pulse to the pulse width at the end of the pulse. The larger the ratio, the stronger the coupling effect. Therefore, in the case of ultra-short pulse laser irradiation, neglecting the thermal coupling effect may cause a large error under the condition that the absolute value of λ is relatively small (on the order of 10 -3 (-3)).