Shunt pulsation trap for cyclic positive displacement (pd) compressors

A positive displacement compressor with a shunt pulsation trap apparatus, comprising:

• a. a housing structure having a flow suction port, a flow discharge port and a compressor cavity, and at least one injection port located before said flow discharge port communicating with said compressor cavity and at least one feedback region communicating with said flow discharge port, and there-between forming a pulsation trap chamber adjacent to said compressor cavity;
• b. a positive displacement driving means mounted inside said housing and mating with said compressor cavity for reducing said cavity volume and propelling flow from said suction port to said discharge port;
• c. a shunt pulsation trap apparatus comprising said trap chamber adjacent to said compressor cavity, therein housed various pulsation dampening means or pulsation energy recovery means or pulsation containment means, at least one trap inlet (said injection port) branching off from said compressor cavity into said pulsation trap chamber and at least one trap outlet (said feedback region) communicating with said compressor discharge port;
• d. whereby said positive-displacement compressor is capable of achieving high gas pulsation and NVH reduction close to source and improving compressor off-design efficiency without using a traditional serial pulsation dampener and a variable geometry.