Pressure ratio

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[Compressor performance]
The capacity of a compressor can be expressed by the degree of pressure rise obtained and the amount of gas it handles. The former is expressed by the pressure at the compressor outlet (discharge pressure) or the ratio p ₂ / p ₁ (pressure ratio ) of the gas pressure at the compressor outlet p ₂ to the pressure at the inlet p ₁ , and the latter is expressed by the flow rate (mass or volume) per unit time. Devices that have a lower pressure rise than compressors are called blowers, and are further divided into fans and blowers. …

*Some of the terms mentioned in "pressure ratio" are listed below.

Source | Heibonsha World Encyclopedia 2nd Edition | Information

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［圧縮機の性能］
　圧縮機の能力は，得られる圧力上昇の程度と取り扱う気体の量で表すことができる。前者は圧縮機出口の圧力(吐出圧力)，または圧縮機出口における気体の圧力p₂と入口における圧力p₁との比p₂/p₁(圧力比)で表し，後者は単位時間当りの流量(質量，もしくは体積)で示す。圧縮機より圧力上昇が低いものは送風機と呼ばれ，さらにファンとブロワーに分けられる。…

※「圧力比」について言及している用語解説の一部を掲載しています。

出典｜株式会社平凡社世界大百科事典 第２版について | 情報