Abstract: An exemplary centrifugal fan includes a casing defining an air outlet, and an impeller in the casing. An air channel is defined in the casing between a sidewall of the casing and outermost free ends of the impeller. The sidewall includes a first curved section adjoining a second curved section. The first curved section is located at a more upstream portion of the sidewall than the second curved section along a rotation direction of the impeller. The first curved section extends along a part of an Archimedes spiral or a part of a logarithmic spiral. The second curved section is located farther away from the impeller than an imaginary extension line of the first curved section along the Archimedes spiral or the logarithmic spiral. An air guide plate is formed in the casing and extends from the air outlet to an inner region of the air channel.

Abstract: A turbine airfoil usable in a turbine engine and including a depth indicator for determining outer wall blade thickness. The airfoil may include an outer wall having a plurality of grooves in the outer surface of the outer wall. The grooves may have a depth that represents a desired outer surface and wall thickness of the outer wall. The material forming an outer surface of the outer wall may be removed to be flush with an innermost point in each groove, thereby reducing the wall thickness and increasing efficiency. The plurality of grooves may be positioned in a radially outer region of the airfoil proximate to the tip.

Abstract: A variable nozzle for a turbocharger (10) has a nozzle ring (138) supporting an array of vanes (134) that are variable in setting angle. The nozzle ring (138) is rotationally oriented and fixed in position by a plurality of circumferentially spaced, radially outwardly extending locating members (170) that engage corresponding locating grooves (159) in a flange member (157) of the turbocharger.