工作于非标准环境下体吸收型激光能量计的研制

研究了能直接工作于非标准环境下的体吸收型激光能量计.由能量计热传导、热对流、热辐射的单位时间热交换方程推导出单位时间内能量计升温过程中热能损失的数学模型,根据数学模型对能量计整个升温过程的热损失进行补偿,使得能量计对于不同脉冲长度入射激光的测量结果重复性由4.7%提高到了0.6%,消除了能量计热损失给测量带来的不利影响.针对环境温度从-40℃变化到70℃测温用铜-康铜热电堆对1℃温差响应电压剧增30%的问题,在环境试验箱进行不同环境温度下的激光能量测量实验,得出了能量计不同环境温度下测量结果的修正系数,并利用最小二乘法建立了修正系数同环境温度之间的函数关系,使得环境温度对测量结果的影响得到了修正.

Bulk absorption laser calorimeter operating in non-standard environment

A bulk absorption laser energy calorimeter operating in non-standard environment was designed. The thermal radiation, conduction and air convection of the calorimeter were analyzed, and its heat exchange equations were derived. The mathematical model of thermal loss of the calorimeter was established. The thermal loss in the process of temperature rising was compensated based on the model. The measurement repeatability error of the calorimeter for different input laser pulses was decreased from 4.7% to 0.6%, and the negative influence of thermal loss was removed. When the copper-constantan thermal couple was used to measure the same temperature difference in different environments, the calorimeter’s output changed greatly, it increased by 30% when the environment temperature increased from -40℃ to 70℃. Laser energy measurements were carried out at different temperatures in an environment controlled chamber, and the correction coefficients of the calorimeter at different temperatures were obtained. The dependence of the coefficients on environmental temperatures was determined by using the least square method. The impact of the environment temperature variation on measurement result was corrected.