摘要
通过研究T-TDR传感器的热传导过程,优化热电偶结点的嵌入位置,提高了传感器测量精度。采用土壤二维热传导方程,利用Heat Transfer数值计算模型,在分析T-TDR探针传热初边值问题的基础上,探讨了T-TDR传感器热场随时间、土壤热传导率、土壤热容等参数变化的关系,模拟了传感器在不同外界环境温度、导热系数和容积热容量土壤中的热传导动态过程和热场空间分布。结果表明,T-TDR传感器中热电偶结点的最优嵌入位置为传感器末端方向上距离探针中点2 mm处,此位置对于中间探针的辐射热量最为敏感。
The measurement accuracy of T-TDR sensor was improved via studying the heat conduction process and optimizing the embedded point of the thermocouple nodes.Using 2-D heat transfer equation in the soil,the initial boundary value of the Heat Transfer of the T-TDR probe was analyzed numerically.Then the relationship between the thermal field of T-TDR with time,thermal conductivity and capacity of soil was established.Furthermore,the dynamic process of heat transfer and spatial thermal distribution of T-TDR at different environment temperature,conductivity and volumetric heat capacity were simulated.The results showed that the optimal positions of the thermocouple node on both sides were on the probe midpoint at 2 mm thermocouple junction of the sensor terminal direction distance.This was the most sensitive point to the radiant heat of the intermediate probe.
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2013年第8期106-111,共6页
Transactions of the Chinese Society for Agricultural Machinery
基金
'十二五'国家科技支撑计划资助项目(2011BAD29B08)
高等学校学科创新引智计划'111'资助项目(B12007)
中央高校基本科研业务费专项资金资助项目(2109021117
QN2011128)
关键词
T-TDR传感器
土壤热传导
热场模拟
土壤温度
土壤水分
T-TDR sensor Soil thermal conduction Thermal field simulation Soil temperature Soil moisture
