Background of the invention

The different thermal engines used to drive a propeller or rotor to produce lift or thrust require a pressure gradient to extract the chemical energy stored in a fuel. A compressor or compression phase is used to increase the pressure in the engine, and the exhaust gases exit the engine and expand at atmospheric pressure. To run the compressor, energy is extracted by a turbine or set of turbines.

This invention called new propeller or rotor design to improve engine efficiency, and propulsive efficiency allows the exhaust gases from the engine to expand at a pressure lower than the atmospheric pressure.

The airfoil used for the blade has a suction side, which is a low-pressure area at the top of the airfoil (extrados). On that low-pressure side, small holes allow the exhaust gases to escape from the blade.

The blade is connected to the exhaust system via a system of pipes, valves, and rotary unions.

Thus, the engine can be downsized by reducing the number of compressor stages and turbine stages or increase the power generated by the engine. Also, the exhaust gases reenergize the flow on the blade. This action will delay flow separation and improve the lift-to-drag ratio of the blade. State of prior art

US6796533B2 shows the method and apparatus for boundary layer reattachment using piezoelectric synthetic jet actuators. However, the fluid used for this device is not from the exhaust system of a thermal machine, and its function is not to lower the back pressure behind a turbine.

US7946801B2 shows the multi-source gas turbine. The function is to cool a turbine blade. Air is taken from the compressor and send inside a hollow turbine blade which has cavities through which air is ejected to create a protective layer for the turbine blade. However, its function is not to lower the back pressure behind a turbine.

US20120027568A1 shows the low-pressure steam turbine and method for operating thereof. Its function is to increase the efficiency of the last turbine stage. The pressure is lowered by condensing the steam. This method requires the condensation of the working fluid from the turbine. On the contrary, the new propeller or rotor blade design to improve engine efficiency and propulsive efficiency does not require a phase change to lower the pressure. Furthermore, there is no condenser needed, and the working fluid can be either a gas or a liquid. Besides, a propulsive force or thrust can be produced by the new propeller or rotor blade design to improve engine efficiency and propulsive efficiency.

Brief Summary of the Invention

The present invention concerns the new propeller or rotor design to improve engine efficiency and propulsive efficiency technically characterized by a blade with exhaust holes or slots placed on the suction side. The suction side has a lower pressure due to the curvature of the airfoil or airfoils used for the conception of the blade. This system can be used as a propeller or rotor blade for a helicopter or airplane.

Brief description of the several views of the drawing

Fig. 1 is a perspective view of the structure supporting the rotor and guiding the exhaust fluid.

Fig. 2 is a profile view of the structure supporting the rotor and guiding the exhaust fluid.

Fig. 3 is a perspective view of the structure supporting the rotor and guiding the exhaust fluid with the bearings mounted on the structure.

Fig. 4 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade.

Fig. 5 is a profile view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade.

Fig. 6 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade and connected to a shaft.

Fig. 7 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade and connected to a shaft driven by an electric motor.

Fig. 8 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade and connected to a shaft driven by an electric motor and an axial turbine placed in front.

Fig. 9 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade and connected to a shaft driven by an electric motor and a centrifugal turbine placed in front. Fig. 10 is a perspective view of the rotor or propeller with blades having the exhaust holes or slots placed on the suction side of the blade and connected to an exhaust pipe from a turbine stage.

Fig. 11 is a perspective view of the rotors or propellers with blades having the exhaust holes or slots placed on the suction side of the blade.

Detailed Description of the Invention

As shown in the drawings: The 1 corresponds to the inlet that allows the exhaust gases from the engine or turbine stage to enter the rotor or propeller. The 2 corresponds to the outlet that allows the exhaust gases from the engine or turbine stage to enter the rotor or propeller. The 3 corresponds to the bearings or rotary unions onto which the rotor or propeller is mounted. A compartment that enclosed the valves that regulate the exhaust gases, the actuator that changes the pitch of the blade, and the electronic control unit that controls the actuator and the valves are enclosed in the rotor or propeller. The 4 corresponds to the rotor or propeller. The 5 corresponds to the holes or slots placed on the suction side of the blades. Also, the tip of the blades (5) allows if necessary the venting of the exhaust fluid to handle higher volume flow rate.

The new propeller or rotor design to improve engine efficiency and propulsive efficiency is made of a blade or series of blades that have holes or slots on their suction side (5). The blade is connected to a thermal engine exhaust system via pipes and rotary unions. There is a pipe inside the blade that allows the exhaust gases to flow toward the slots or holes (5). The valves direct the exhaust gases toward the blades of the rotor or propeller and regulate the flow. The pitch angle of the blade can be varied, and in that case, another rotary union is placed at the hinge point (8). The piping system inside the blade can have thermal insulation, thus avoiding the high temperature to affect the materials and structural integrity of the blade adversely if needed. Furthermore, the valves are linked to an electronic control system that closes the valve, thus cutting the flow of hot gases into a blade. Another valve, connected to ambient air via an air intake, allows cold air to flow cyclically inside the blade. This will allow the excessive heat to be removed, keeping the blade within an acceptable temperature range.

In case of a valve malfunction, a wastegate is installed within the exhaust system and will allow the venting of the exhaust gases, thus bypassing the blades.

Also, the new propeller or rotor design to improve engine efficiency and propulsive efficiency can be placed behind an axial (10) or centrifugal turbine (11) or turbine stages. It can also be placed behind the turbine compartment of a turbocharger (13). The turbocharger compressor (14) can be connected to an electrical generator (15) that transforms the extra shaft power from the turbine into electricity. The rotor is connected to the turbocharger via a rotary union (3). Also, the rotor can be connected to the turbine via a shaft and a gearbox that turns the rotor at a prescribed rotational speed. Another way to spin the rotor is to use an engine crankshaft (7) directly with a gearbox system (6) or an electrical motor (9).

Many rotors or propellers can be mounted in parallel to handle a higher volume flow rate (fig.

11).

The new propeller or rotor design to improve engine efficiency and propulsive efficiency can be used with any thermal engine (piston engine, gas turbine, turboshaft, turboprop) or boosting system (turbocharger).