电荷耦合器件(charge coupled device,CCD)成像技术在火焰温度场测量中有广泛的应用,讨论基于CCD测量火焰温度场的反演计算误差。彩色CCD的三基色波段响应输出往往被简化为3个单色波长输出,并通过黑体实验或具体的CCD光谱响应函数标定简化引起的偏差,然而标定处理不能保障3个基色波长假设在非灰性介质测量中的准确性。因此,以具有特定发射率表现的火焰诊断温度场测量为例,通过数值模拟计算,定量分析计算温度和发射率参数的相对误差分布规律。结果表明,发射率参数的计算相对误差要远远大于温度的相对误差。结论有利于采用CCD成像技术进行火焰温度场测量的计算准确性的改善。
Charge coupled device (CCD) image technique is widely used in the flame temperature field measurements. Inverse calculation errors of flame temperature filed measure-ements based on color CCD was discussed. Spectral responses of color CCD are usually simplified as three-wavelength responses, and the temperature measurement deviation arising from this simplification may be calibrated through blackbody experiments or known actual CCD spectral responses functions. However, it doesn't guarantee the inverse calculation accuracy under the assumption of three-wavelength responses applied in the non-gray object measurements. Therefore, choosing the non-gray flame with the specified emissivity as the investigated example, quantitatively analyzed the distributions of the inverse calculation errors of the temperature and the emissivity parameter through numerical simulations. The results show that the inverse calculation errors are remarkable, and the relative error of emissivity parameter is larger than the relative error of temperature. The conclusion is helpful to improve the calculation accuracy of non-gray flame temperature field measurements adopting CCD image technique.