摘要
研究地应力与瓦斯压力共同作用下煤体吸附解吸煤层瓦斯时的温度演化趋势有重要意义,但也发现实验数据因含有较多的噪声而很难获得其真实信号,为此,针对不同实验条件下获得的煤体吸附解吸煤层瓦斯时的温度信号演化的特点,拟采用基于MATLAB的小波去噪方法剔除噪声还原真实信号,以得到真实温度演化曲线。通过对几种常用小波基函数和不同分解层数的对比分析,选用了消失矩阶数较高、光滑性较好的sym8小波基函数中的8层分解,其重构后的温度信号基本去除了高频的噪声信号,且较好地保留了低频以及平稳信号。结果表明,其去噪效果较好,能够较好地反映煤体在吸附、解吸煤层瓦斯过程中温度的演化规律。
The study on the temperature evolutionary trend under both the ground stress and gas pressure is significant in the process of coal gas absorption and desorption.However,the valid signal is difficult to gain because of much noise in the experimental data,so according to the characteristics of the temperature signal gained under different experimental conditions of coal gas absorption and desorption,this essay filtrates noise and restores the valid signal by using the wavelet denoising of MATLAB to obtain the valid temperature evolutionary curve.Through contrasting and analyzing wavelet basis function and different decomposition levels,the essay chooses the sym8 wavelet basis function which has a higher order of vanishing moments and better smoothness.The reconstructed signal filtrates most of high frequency signal,and keep low frequency,as well as smooth signal.The result shows that the de-noising effect is good and the temperature evolution rule can be well reflected in the process of the coal gas absorption and desorption.
出处
《重庆大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2011年第7期76-82,共7页
Journal of Chongqing University
基金
国家自然科学基金项目(50974141)
国家重点基础研究发展计划(973计划)资助项目(2011CB201203)
国家科技重大专项项目(2011ZX05034-004)
中央高校基本科研业务费资助(CDJXS11240001)
重庆大学'211工程'三期创新人才培养计划建设项目(S-10220)
关键词
小波去噪
煤层瓦斯
吸附解吸
温度
wavelet denoising
coal gas
absorption and desorption
temperature
