empirical constant meaning in Chinese

经验常数

However , the formulas describing whole fcp curve above - mentioned contain some empirical constants without distinct definition
但这些表达式中均含有物理意义不明确、需由实验确定的常数。
Comparison between the computations and field tests shows that the software can provide reliable predictions for natural ventilation cases and that the values for empirical constants including train friction coefficient used by the model are in the proper range
通过数值计算结果与现场试验结果的对比，说明该程序对隧道自然通风的计算结果是正确可靠的，同时，也说明了数值计算所采用的物理及数学模型和列车摩阻系数都是合适的。