second thrust bearing 42 supports the downstream end of the axis 16 supported in a frame portion 44 within the downstream end of the compressor housing 28 the downstream side of the compressor unit 12 is in fluid communication with a plurality of channels 46 which extend from the fluid stage 34 s 34 of the compressor unit 12 to a nozzle ring 48 having a plurality of nozzles 50 therein as shown in fig1 the channels 46 are arranged in a conical configuration and conduct a portion of the air from the final compressor stage 34 s 34 one channel 46 for each nozzle 50 to each nozzle 50 each nozzle 50 is disposed so as to direct fluid air in a tangential manner into a cylindrically shaped converging diverging shaped tube 52 each nozzle 50 is also directed rearwardly so as to give the fluid a gyrating or rectilinear flow path particularly adjacent the inner wall of the converging diverging tube the interior design of the converging diverging tube 52 shown generally in fig1 will be discussed in detail below with reference to fig6 the tube 28 includes a converging section 43 a short straight section 45 a diverging section 47 and a long straight section 49 the converging diverging tube 52 has an upstream end which is in fluid communication with the downstream end of the compressor housing 28 which also comprises the outer housing for the impeller 40 the impeller 40 being arranged on the axis 16 common with the drum 32 and the fan 14 therefore rotates in the same.