单选:平行固体壁之间的流体流态的判别准则为,实际雷诺数Re大于()时就是紊流,而小于该值一定为层流。

题目内容:
平行固体壁之间的流体流态的判别准则为,实际雷诺数Re大于()时就是紊流,而小于该值一定为层流。
A.1000
B.2000
C.3000
D.4000
参考答案:

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