煤泥抗拉强度特性试验研究  

Experimental study on tensile strength characteristics of coal slime

作　　者：范浩东 史鉴 杨海瑞[1] 吕俊复[1] 金燕[2] 高琴[3] 张缦[1] 秦舒宁 周宝 FAN Haodong;SHI Jian;YANG Hairui;LÜJunfu;JIN Yan;GAO Qin;ZHANG Man;QIN Shuning;ZHOU Bao(Department of Energy and Power Engineering,Tsinghua University,Beijing 100084,China;College of Electrical and Power Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Shanghai Boiler Works Co.Ltd.,Shanghai 200245,China)

机构地区：[1]清华大学能源与动力工程系,北京100084 [2]太原理工大学电气与动力工程学院,山西太原030024 [3]上海锅炉厂有限公司,上海200245

出　　处：《中南大学学报（自然科学版）》2022年第10期4142-4149,共8页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(U1810126)。

摘　　要：为了研究煤泥抗拉强度进而判断煤泥的入炉形态,设计一套单轴拉伸试验系统来测量煤泥的抗拉强度,通过试验确定煤泥最佳静置时间及步进伺服电动机拉伸速率,并研究不同含水率及压实度对煤泥抗拉强度的影响规律。研究结果表明:当静置时间小于等于2 d时,煤泥的抗拉强度及其增速随着静置时间的延长而增大,而后,随着静置时间进一步延长,煤泥的抗拉强度趋于不变;拉伸速率通过影响煤泥内部的孔隙水压力进而影响煤泥抗拉强度,过大或过小的拉伸速率都会使测量结果产生较大误差,选取0.8 mm/min拉伸速率可有效避免端部应力集中的影响;含水率与煤泥抗拉强度之间呈负相关关系,含水率越大,煤泥抗拉强度越小,当含水率由25.12%增加至35.17%时,煤泥抗拉强度从25.23 kPa减小至21.39 kPa;压实度与煤泥之间呈正相关关系,压实度越大,煤泥抗拉强度呈线性增大,当压实度从85 g增加至100 g时,煤泥抗拉强度从19.44 kPa增加至29.92 kPa。A uniaxial tensile test system was developed to measure the tensile strength of coal slime in order to study the tensile strength of coal slime and then judge the morphology of coal slime into the furnace.The optimum dwell time of coal slime and the tensile rate of stepping servo motor were determined by experiments.The influence law of different water content on the tensile strength of coal slime was studied.The results show that in the first two days,the longer the dwell time is,the greater the tensile strength of the coal slime is,and the faster the growth rate is.After that,with the increase of the dwell time,the tensile strength of the coal slime tends to be unchanged.The tensile rate affects the tensile strength of the coal slime by affecting the pore water pressure inside the slime.When tensile rate is too large or too small,large error will occur in the measurement results.The 0.8 mm/min tensile rate can effectively avoid the influence of stress concentration at the end.There exists a negative correlation between the water content and the tensile strength of coal slime.The higher the water content is,the smaller the tensile strength of slime is.When the water content increases from 25.12%to 35.17%,the tensile strength of coal slime decreases from 25.23 kPa to 21.39 kPa.There exists a positive correlation between compression degree and coal slime.The tensile strength of coal slime increases linearly with the degree of the compression.When the compression degree increases from 85 g to 100 g,the tensile strength of coal slime increases from 19.44 kPa to 29.92 kPa.

关 键 词：煤泥 单轴拉伸 含水率 压实度 静置时间 拉伸速率 

分 类 号：TK0[动力工程及工程热物理]