Diffuser including vaneless and vaned sections

Claim 2

In a turbomachine, a diffuser for conditioning fluid flow of at least transonic speed from a rotor and transmitting it to a collector means, the diffuser comprising an annularly open region for receiving fluid flow from the rotor, the annularly open region being formed by spaced apart walls for conditioning fluid flow from the rotor, a diffuser section comprising means forming multiple tangential channels for delivering fluid flow to the collector means, and a transition section for delivering fluid flow from the annularly open region to the multiple channel diffuser section, the annularly open diffuser region having a convergent-divergent configuration selected to produce a condition of imminent boundary layer separation, the transition section being configured for maintaining the condition of imminent boundary layer separation, each of the multiple channels also having a convergent-divergent configuration in a downstream direction selected to establish a condition of imminent boundary layer separation.

Claim 3

In a turbomachine, a diffuser for conditioning fluid flow of at least transonic speed from a rotor and transmitting it to a collector means, the diffuser comprising an annularly open region for receiving fluid flow frOm the rotor, the annularly open region being formed by spaced apart walls for conditioning fluid flow from the rotor, a diffuser section comprising means forming multiple tangential channels for delivering fluid flow to the collector means, and a transition section for delivering fluid flow from the annularly open region to the multiple channel diffuser section, at least a portion of the diffuser having a cross section which converges and then diverges in the direction of flow to establish and maintain a condition of imminent boundary layer separation in order to minimize boundary layer losses, the initial portion of the annularly open diffuser region converging in the direction of flow for accelerating the velocity of fluid flow from the rotor, the rotor being of a type for delivering fluid flow radially outwardly from its periphery, the spaced apart walls forming the annularly open region being arranged in substantially radial relation to the rotor, the multiple channel diffuser section means being a plurality of elements circumferentially arranged between walls spaced apart in substantially radial relation to the rotor, surfaces of the plurality of elements forming opposite sides of each channel being generally parallel, the spaced apart walls in the multiple channel diffuser section converging toward each other and then diverging in a downstream direction for producing a condition of imminent boundary layer separation.

Claim 4

In a turbomachine, a diffuser for conditioning fluid flow of at least transonic speed from a rotor and transmitting it to a collector means, the diffuser comprising an annularly open region for receiving fluid flow frOm the rotor, the annularly open region being formed by spaced apart walls for conditioning fluid flow from the rotor, a diffuser section comprising means forming multiple tangential channels for delivering fluid flow to the collector means, and a transition section for delivering fluid flow from the annularly open region to the multiple channel diffuser section, at least a portion of the diffuser having a cross section which converges and then diverges in the direction of flow to establish and maintain a condition of imminent boundary layer separation in order to minimize boundary layer losses, the initial portion of the annularly open diffuser region converging in the direction of flow for accelerating the velocity of fluid flow from the rotor, the rotor being of a type for delivering fluid flow radially outwardly from its periphery, the spaced apart walls forming the annularly open region being arranged in substantially radial relation to the rotor, the multiple channel diffuser section means being a plurality of elements circumferentially arranged between walls spaced apart in substantially radial relation to the rotor, surfaces of the plurality of elements forming opposite sides of each channel being generally parallel, the spaced apart walls in the multiple channel diffuser section converging toward each other and then diverging in a downstream direction for producing a condition of imminent boundary layer separation.