摘要 |
A rotary positive displacement machine for operation both as a compressor and an expander comprises a casing (6) housing intermeshing male and female rotors (2, 3), the casing (6) including a fluid inlet and a fluid discharge for fluid to be compressed or expanded, and drive means (9, 10) enabling driving of the rotors (2, 3) separately from each other so that the machine can operate as a dry machine. The rotors (2, 3) intermesh via lobes (4, 5) whose profiles are produced by a co-generation process, the male lobe (4) having a symmetric transverse profile of varying curvature while the opposite flanks (5L, 5T) of the female lobe (5) are generally concave but with a substantially straight portion at the tip arranged such that each female lobe (5) diverges at the tip. The machine enables leakage blow holes to be reduced both for the compressing and expansion modes of operation. |