【摘要】 在利用可调谐二极管激光吸收光谱技术测量二氧化碳气体浓度的过程中,气体压强的变化会对吸收谱线展宽、波长调制系数和二次谐波信号幅值产生影响。基于可调谐二极管激光吸收光谱技术,在不同的压强下利用二次谐波峰峰值和一次谐波平均值测量二氧化碳气体的浓度,通过压强补偿抑制气室内压强变化所带来的测量误差。实验结果表明:利用压力补偿后系统的测量误差在2%以内,可以有效地抑制气体压强变化的影响,提高二氧化碳气体浓度测量的精度。更多还原

【Abstract】 In the measurement of the carbon dioxide concentration using tunable diode laser absorption spectroscopy,the variation of pressure has influence on the line width of carbon dioxide absorption line,the wavelength modulation coefficient and the signal amplitude of second harmonic signal. Under different pressures,the concentration of carbon dioxide was measured using the second harmonic peak to peak value and the first harmonic mean value based on tunable diode laser absorption spectroscopy technique,and the measurement error caused by pressure change was inhibited by pressure compensation. Experimental results show that the system measurement error is within 2% using pressure compensation function,and this system can inhibit the effect of gas pressure change effectively and improve the measurement accuracy of the carbon dioxide concentration.更多还原