不同固体表面下激光多普勒测速的数值模拟

激光多普勒测速仪(LDV)的测量精度和应用受到光电探测器、环境状况、频谱加宽和信号处理等因素影响。本文根据条纹模型和散射机理建立了固体LDV的数学模型，并通过数值模拟详细分析了固体表面特性和测量精度之间的关系，实验结果和数值模拟结果符合得很好。LDV能够精确地测量出固体表面运动速度，但要求被测固体的表面粗糙度在一定范围内，而且这个范围由条纹间距和有效探测体宽度决定。

Numerical Simulation of Laser Doppler Velocimeter Systems Operating on Various Solid-state Surfaces

The applicability and accuracy of laser Doppler velocimeters(LDV) depend on the conditions in which the system operates:the characteristics of the surface measured,photoelectric detector,the environmental conditions,spectrum broadened,signal processing,etc.In this paper,based on a theoretic model of fringes and the principle of light interfering and scattering,a mathematic model of LDV for solid-state surfaces has been developed and we analyzed the relationship between the characteristics of the solid-state surface and the measurement accuracy for velocity through computer simulation in details,the results of experiment accord with the results of simulation exactly.The analysis leads to the conclusion that LDV system can measure precisely the speed of moving solid-state surface,and surface roughness is within the range depending on the measuring volume and fringe spacing.