求翻译：综合上面的叙述，将换热和压降这些因素综合考虑在内，同时考虑级数的增加给加工带来的难度特性，我们选择的最佳通道级数为3级是什么意思？

Comprehensive the above description, the heat transfer and pressure drop these factors into consideration, taking into account the series to increase the difficulty to processing characteristics, we select the best channel series 3

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Synthesizes above narration, the heat transfer and the pressure drop these factor overall evaluation, simultaneously considered the progression the increase the difficulty characteristic which brings to the processing, we choose the best channel progression is 3 levels

Comprehensive described above, heat and pressure drop for taking these factors into account, taking into account the progression of increasing difficulty brought to processing characteristics, we choose the best series for the channel 3

正在翻译，请等待...