Abstract: Rotary heat exchangers can include a ride-along compressor, at least a portion of which can be rotated along with the heat exchanger. By rotating at least a portion of the compressor along with the heat exchanger, a sealed fluid circuit containing a two-phase working fluid can be provided. A rotary heat pump or heat engine can include an evaporator and a condenser in the form of back-to-back centrifugal fans. The centrifugal fan blades or other portions of the evaporator and condenser may include internal cavities where the working fluid undergoes a phase change.

Abstract: A reflective concentrator can include a primary reflector and a secondary reflector located radially outward of the primary reflector. The primary reflector can be a rotationally-symmetric, convex conical shape, radial sections of which may include an off-axis parabolic reflector with a focal point radially outward of the primary reflector. A secondary reflector may be located radially outward of the primary reflector, and may include a rotationally symmetric section of a toroidal space surrounding the primary reflector. In some embodiments, the secondary reflector may be convex or concave. Incident sunlight generally aligned with a rotational axis of symmetry of the primary reflector may be reflected off of the primary reflector, off of the secondary reflector, and back towards a point near the central peak of the primary reflector. The reflective concentrator may be aerodynamically stable, and may include an aerodynamic fairing on its read side to further increase the aerodynamic stability of the structure.

Abstract: Rotary heat exchangers can include a ride-along compressor, at least a portion of which can be rotated along with the heat exchanger. By rotating at least a portion of the compressor along with the heat exchanger, a sealed fluid circuit containing a two-phase working fluid can be provided. A rotary heat pump or heat engine can include an evaporator and a condenser in the form of back-to-back centrifugal fans. The centrifugal fan blades or other portions of the evaporator and condenser may include internal cavities where the working fluid undergoes a phase change.

Abstract: Rotary heat exchangers can include a ride-along compressor, at least a portion of which can be rotated along with the heat exchanger. By rotating at least a portion of the compressor along with the heat exchanger, a sealed fluid circuit containing a two-phase working fluid can be provided. A rotary heat pump or heat engine can include an evaporator and a condenser in the form of back-to-back centrifugal fans. The centrifugal fan blades or other portions of the evaporator and condenser may include internal cavities where the working fluid undergoes a phase change.