A turbomachine comprising: a rotating group with a turbine wheel; a housing that houses the rotating group, the housing defining a turbine outlet passage for exhaust from the turbine wheel, the turbine outlet passage directed in a downstream direction along an axis of the turbine outlet passage; and an air bearing system with at least one bearing component that supports the rotating group for rotation relative to the housing, the air bearing system including a bearing cooling path that is fluidly connected to the at least one bearing component and that has a bearing air line outlet, the bearing air line outlet fluidly connected to the turbine outlet passage and directed in the downstream direction along the axis, wherein the housing includes a turbine housing that covers over the turbine wheel, the turbine housing including the turbine outlet passage, the turbine housing including the bearing air line outlet, the turbine housing at least partly defining a circumferential flow passage disposed upstream of the turbine wheel; wherein the bearing air line outlet is disposed radially outward from the circumferential flow passage with respect to the axis; wherein the turbine housing includes an outer turbine housing and an inner turbine housing that cooperatively house the turbine wheel and that cooperatively define the circumferential flow passage, the outer turbine housing covering over a front face of the turbine wheel, and the inner turbine housing covering over a back face of the turbine wheel; wherein the outer turbine housing includes the turbine outlet passage and the bearing air line outlet and the inner turbine housing includes a nozzle structure that extends about the turbine wheel, the nozzle structure including at least one nozzle aperture directed toward the turbine wheel; characterised in that the turbine housing includes a recirculation flow path (182, 282, 382, 482) that extends from the circumferential flow passage, through the nozzle structure, and back to the circumferential flow passage. a rotating group with a turbine wheel; a housing that houses the rotating group, the housing defining a turbine outlet passage for exhaust from the turbine wheel, the turbine outlet passage directed in a downstream direction along an axis of the turbine outlet passage; and an air bearing system with at least one bearing component that supports the rotating group for rotation relative to the housing, the air bearing system including a bearing cooling path that is fluidly connected to the at least one bearing component and that has a bearing air line outlet, the bearing air line outlet fluidly connected to the turbine outlet passage and directed in the downstream direction along the axis, wherein the housing includes a turbine housing that covers over the turbine wheel, the turbine housing including the turbine outlet passage, the turbine housing including the bearing air line outlet, the turbine housing at least partly defining a circumferential flow passage disposed upstream of the turbine wheel; wherein the bearing air line outlet is disposed radially outward from the circumferential flow passage with respect to the axis; wherein the turbine housing includes an outer turbine housing and an inner turbine housing that cooperatively house the turbine wheel and that cooperatively define the circumferential flow passage, the outer turbine housing covering over a front face of the turbine wheel, and the inner turbine housing covering over a back face of the turbine wheel; wherein the outer turbine housing includes the turbine outlet passage and the bearing air line outlet and the inner turbine housing includes a nozzle structure that extends about the turbine wheel, the nozzle structure including at least one nozzle aperture directed toward the turbine wheel; characterised in that the turbine housing includes a recirculation flow path (182, 282, 382, 482) that extends from the circumferential flow passage, through the nozzle structure, and back to the circumferential flow passage.