Flow velocity, at this location, can never exceed the local speed of sound, and is said to be in a choked condition.

流速，在这个位置，绝不能超过当地音速的，据说是在一个呛条件。

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Here the gas velocity corresponds to a Mach number of one, denoting that the flow velocity is equal to the local speed of sound of the particular gas.

在这里，气速对应到一个马赫数之一，指该流速等于当地音速的，特别是天然气。

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The emerging sunspot region seems to boost the local speed of sound, thereby hastening the refracted return of sound waves passing through that part of the solar interior.

浮现的黑子区似乎能使当地的声速增加，从而使声波更快地通过这个区域。

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