A fan apparatus is described that comprises a rotational hub that defines a central axis, a first fan blade coupled to the rotational hub and extending radially outward from the central axis, wherein the first fan blade has a first pitch angle; a second fan blade coupled to the rotational hub and extending radially outward from the first central axis, wherein the second fan blade has a second pitch angle opposite the first pitch angle; and a housing that defines cylindrical interior volume with a central axis coaxial with the central axis of the rotational hub, wherein the first and second fan blades reside within the cylindrical interior volume.

An evaporated fuel processing device includes a fuel tank, a canister, an atmospheric passage, a vapor passage, an intake pipe, a purge passage, a purge pump, and a flow rate control valve. The evaporated fuel is desorbed utilizing only negative pressure in the intake pipe when sufficient negative pressure is generated in the intake pipe. The purge pump is driven to desorb the evaporated from the canister when sufficient negative pressure is not generated in the intake pipe. The purge pump and the flow rate control valve may be provided in the purge passage. The purge pump is a vortex pump through which the gas can flow even when drive is stopped. The minimum cross-sectional area of the internal space of the flow passage of the purge pump is equal to or larger than the minimum cross-sectional area of the internal space of the other parts of the purge passage.

The invention relates to an impeller (1), in particular for a side channel machine, comprising blades (5) arranged distributed in the circumferential direction and formed in each case by a blade wall (6), which blades form open blade chambers (4) in a plan view onto the impeller (1), wherein a blade wall (6) in the plan view starts at a first radius dimension (r.sub.1) related to the geometrical impeller rotation axis (x), which first radius dimension (r.sub.1) corresponds to half or more than half of a second radius dimension (r.sub.2), which second radius dimension (r.sub.2) defines a circumferential rim edge (9) of the impeller (1), and wherein the radius dimension (r.sub.1) defines a radially inner boundary wall (7) of the blade chamber (4), wherein furthermore a blade wall (6) comprises an exposed upper terminating edge, which runs correspondingly radially on the inside into the inner boundary wall (7) and ends radially on the outside in plan view, wherein an imaginary connecting line (V) can be drawn between a run-in point of the terminating edge (12) into the inner boundary wall (7) and a radially outer end of the terminating edge (12) and the terminating edge runs normal to the connecting line (V) with a different offset dimension, wherein a greatest offset dimension results. For the advantageous development, in particular with regard to improved efficiency, it is proposed that the greatest offset dimension corresponds to 0.1 times or more the difference between the second (r.sub.2) and the first radius dimension (r.sub.1).

The invention relates to a compressor arrangement for compressing a gas. The compressor arrangement comprises a drive unit with a driveshaft that can be driven in rotation and at least one compressor which comprises a compressor casing, at least one gas inlet opening formed in the compressor casing and at least one gas outlet opening formed in the compressor casing and fluidically connected to the at least one gas inlet opening. The compressor also has at least one impeller, which is arranged in the compressor casing, is connected in fixed rotation with the driveshaft and can be driven in rotation, for delivering the gas from the at least one gas inlet opening to the at least one gas outlet opening, and has at least one bearing device for bearing the at least one impeller, wherein the at least one bearing device is arranged on the compressor casing and on the at least one impeller.

A gas turbine engine, with a conical screw integrated compression system, that utilizes at least one conical screw as an intermediary fluid transport device to facilitate the multi-staging of non-axial compressors, such as centrifugal and diagonal compressors, as well as or alternatively to combine non-axial compressors to axial compressors and to the fan. The conical screw in the compression system applies axial flow translation and funnels, as necessary, the exit flow of the impeller, fan or compressor into the next impeller or compressor.

A fluid working machine comprises a rotor (7) with a blading (10) comprising 40 to 65 blades that radially project out of a body central and are suitably circumferentially offset on a plane normal to the axis of symmetry of the rotor, according to an appropriate spacing rule that can eliminate or appreciably attenuate the acoustic emission components that are mostly annoying to the human ear or at frequencies close to the resonance frequencies of other parts of the working machine.

An impeller for a side channel flow machine has impeller blades. An inlet region of the impeller blade is off-set from the outlet region. The inlet region is connected to the outlet region via a sloped transition region. The impeller allows a high degree of efficiency of the side channel flow machine and can be produced at particularly low cost.

A power module includes a turbine arranged along a rotation axis, an interconnect shaft fixed in rotation relative to the turbine, and a compressor with a regenerative compressor wheel. The regenerative compressor wheel is fixed in rotation relative to the interconnect shaft supported for rotation with the turbine about the rotation axis. Generator arrangements, unmanned aerial vehicles, and methods of generating electrical power are also described.

A cooling fan structure with rotational cylindrical fan vanes includes a rotary body and multiple rotational cylindrical bodies. The rotary body includes a rotor assembly and a stator assembly corresponding to the rotor assembly for driving the rotor assembly to rotate. The rotor assembly includes a hub. The hub has a top section and a circumferential section. The rotational cylindrical bodies are rotatably disposed on the top section or the circumferential section of the hub. When the rotary body rotates, the rotational cylindrical bodies are driven by the rotary body to self-rotate.

A heat-dissipation fan includes a rotary assembly and a plurality of rotary cylinders mounted on an outer surface of the rotary assembly to serve as cylindrical fan blades of the heat-dissipation fan. The rotary assembly includes a plurality of first electrical conducting units and a second electrical conducting unit. The rotary cylinders move along with the rotary assembly when the latter rotates and are correspondingly electrically connected to the first electrical conducting units to be rotatable about their respective centerlines.