But now the domestic heat exchange ventilators, most of which are forms of cross-flow, and their heat recovery effectiveness can hardly be improved.

但是如今国内生产的全热交换器，大部分都是叉流形式的，热回收效率难以得到提高。

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But now the domestic heat exchange ventilators, most of which are forms of cross-flow, and their heat recovery effectiveness can hardly be improved.

但是如今国内生产的全热交换器，大部分都是叉流形式的，热回收效率难以得到提高。

youdao