This paper proposes and demonstrates the use of inverse methods to estimate grain properties during deep-bed drying. An inverse analysis was performed to estimate the bulk density, specific heat and initial moisture content of cereal grains, using only grain temperature measurements as inputs. Grain temperature data obtained from numerically solving the direct problem were used to generate the temperature measurements. An iterative procedure, based on minimizing a sum of squares function with the conjugate gradient method and the discrepancy principle, was used to solve the inverse problem. A statistical analysis was performed to evaluate the accuracy of the estimated results. The effects of measurement errors and the sensor location on the inverse solution were also investigated. The close agreement between the exact and the estimated results shows the capability of the proposed method in estimating unknown parameters.

中文翻译：

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谷物深层干燥过程中谷物热物理性质和初始含水量的逆估计

本文提出并演示了使用逆方法来估计深床干燥过程中的谷物特性。进行逆分析以估计谷物的堆积密度、比热和初始水分含量，仅使用谷物温度测量作为输入。通过数值求解直接问题获得的谷物温度数据用于生成温度测量值。迭代程序，基于使用共轭梯度法和差异原理最小化平方和函数，用于解决逆问题。进行统计分析以评估估计结果的准确性。还研究了测量误差和传感器位置对逆解的影响。