阿贝尔逆变换数据处理算法在电弧诊断中的应用

提出了一种由等离子体辐射投影值重建发射系数的阿贝尔逆变换数据处理算法。采用计算简单、变换精度高的Bockasten插值方法实现阿贝尔逆变换积分方程的离散化。在阿贝尔逆变换前,运用傅里叶变换频域低通滤波去除实验数据中的噪声,通过多项式插值弥补数据采样率过低、提高空间分辨力,并对投影数据进行对称化处理以消除数据偏离对称对结果的影响。运用此算法对实验数据进行处理,得到电流200 A、弧长5 mm电弧温度在阴极下方0.5 mm处最高,超过22000 K,与文献中结果一致。该算法能够有效地克服噪声对变换结果的影响,运算速度快、计算精度高、稳定性好,处理大量数据时具有明显的优势。

A Data Processing Method for Abel Inversion in Arc Plasma Diagnostics

A method is proposed for calculating the radially distributed emission coefficients of arc plasmas from the projections.The reconstruction is implemented by using a simple and accurate discrete Abel inversion method which is based on Bockasten's polynomial spline technique.The collected data are filtered in the frequency domain with a lowpass filter to reduce the noise,followed by interpolation for avoiding problems caused by undersampling and increasing data space resolution,and symmetrization for obtaining more accurate results.The arc temperature distribution deduced by the algorithm shows that for a 200 A,5 mm argon arc,the highest temperature near the cathode is more than 22000 K,which agrees well with results of other researches.This algorithm effectively reduces the influence of noises,and it is very steady and fast,which makes advantages in the processing of large amounts of data.