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WORKING OF VANE - TYPE COMPRESSOR

Rotary positive displacement machines are generally uncooled and the compression is largely adiabatic. These are two types :

Roots blower and vane -type compressor.

Vane - Type Compressor :




Vane - type compressor consists of a rotor mounted eccentrically in the body and supported by ball-and -   roller bearings at the ends. The rotor is slotted to take the blades which are of non-metallic material,   usually fibre or carbon. As each blade moves past the inlet passage, compression begins due to   decreasing volume between rotor and casing. delivery begins with the arrival of each blade at the   delivery passage. The p-V diagram is shown where Vs is induced volume at state p1,T1. Compression   occurs to the pressure pi isentropically At this pressure the displaced gas is opened to the receiver and the   gas flowing back from the receiver raises the pressure irreversibly to p2. The work input is given by the   sum of the areas A and B. For a given air flow and pressure ratio the vane type requires less input than the Roots blower




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