Which type of compressor would use a series of vanes to compress gas?

The rotary compressor relies on the motion of a series of vanes to compress gas. In these compressors, the vanes slide in and out of a rotor, which spins within a cylindrical housing. As the rotor turns, the vanes trap gas in pockets and compress it by reducing the volume of these pockets. This type of compressor is renowned for its efficiency and ability to provide continuous gas flow.

The other types of compressors mentioned do not utilize a series of vanes for compression. Liquid ring compressors use a rotating fluid ring to create a seal for compressing gas. Dynamic compressors generally utilize high-speed rotating elements to impart velocity to the gas, which is then converted to pressure, while reciprocating compressors compress gas using a piston that moves back and forth within a cylinder, rather than utilizing vanes. Thus, the rotary compressor is the appropriate choice for the mechanism involving vanes in gas compression.