Thermal hydraulic propulsion system

Abstract

A hydraulic propulsion system converts heat or thermal energy into hydraulic energy, and such hydraulic energy into mechanical work. The hydraulic propulsion system includes a thermal unit, a hydraulic cylinder with pistons and springs mounted therein, one or more hydraulic motors, one or more hydraulic accumulators, and one or more electrical energy generators, as well as a plurality of flow control valves to control the flow of hydraulic fluid between the various components. The hydraulic propulsion system may be enhanced by an energy transmission unit including a wave generator.

1 . A thermal hydraulic propulsion system, comprising:
 a thermal unit including a hydraulic fluid reservoir thermally coupled to a heat source and to a first hydraulic conduit carrying a dilating hydraulic fluid, wherein the hydraulic fluid reservoir exchanges heat between the heat source and the dilating hydraulic fluid, the first portion of the first hydraulic conduit connecting to a first flow control valve and to a first chamber of the hydraulic cylinder via first portion of the intermediate conduit; and   an integrated hydraulic power and control unit including a hydraulic motor hydraulically coupled to a mechanical device and to a second portion of the first hydraulic conduit carrying a working hydraulic fluid that is different than the dilating hydraulic fluid, wherein the hydraulic motor transfers hydraulic energy from the working hydraulic fluid to mechanically power the mechanical device, the second portion of the first hydraulic conduit connecting to a second flow control valve and to a second chamber of the hydraulic cylinder via second portion of the intermediate conduit.   
     
     
         2 . The propulsion system of  claim 1 , further comprising a transmission unit that includes an energy wave generator and an energy wave converter,
 wherein the wave generator includes the heat source that heats the hydraulic fluid reservoir and generates pressure from the dilating hydraulic fluid in the hydraulic fluid reservoir, initiating a high-pressure wave that travels along the first hydraulic conduit, through the first flow control valve to a first chamber of the energy wave converter, the energy wave converter including the hydraulic cylinder, the hydraulic cylinder containing a first piston, a spring and a second piston,   wherein the dilating hydraulic fluid in the energy wave converter exerts pressure against the first piston, compressing the spring that moves the second piston, and initiating a pressure wave in the working hydraulic fluid that travels through the second flow control valve to the hydraulic motor.   
     
     
         3 . The propulsion system of  claim 2 , wherein the hydraulic motor is coupled to the mechanical device by a shaft, and wherein the mechanical device is a wheel. 
     
     
         4 . The propulsion system of  claim 3 , wherein the propulsion system further comprises a second hydraulic motor hydraulically coupled to a second wheel, a third hydraulic motor hydraulically coupled to a third wheel, and a fourth hydraulic motor hydraulically coupled to a fourth wheel. 
     
     
         5 . The propulsion system of  claim 2 , wherein the dilating hydraulic fluid has a first coefficient of thermal expansion and the working hydraulic fluid has a second coefficient of thermal expansion that is lower than the first coefficient of thermal expansion. 
     
     
         6 . The propulsion system of  claim 2 , further comprising a hydraulic accumulator. 
     
     
         7 . The propulsion system of  claim 2 , further comprising an electrical energy generator. 
     
     
         8 . A method of operating a thermal hydraulic pressure wave-based propulsion system, comprising:
 heating a dilating hydraulic fluid within a first conduit coupled and generating pressure from the dilating hydraulic fluid within a pressure wave generator;   positioning a first flow control valve in a closed position to increase pressure of the dilating hydraulic fluid in the first conduit connected to an energy wave converter;   moving the first flow control valve from the closed position to an open position to release a pressure wave in a working hydraulic fluid within a second conduit; and   using the pressure wave in the working hydraulic fluid to provide energy to a hydraulic motor.   
     
     
         9 . The method of  claim 8 , wherein the energy wave converter includes a hydraulic cylinder containing a first piston connected to a second piston by a spring, and wherein moving the first flow control valve from the closed position to an open position to release a pressure wave in a working hydraulic fluid within a second conduit further comprises:
 enabling the dilating hydraulic fluid to exert pressure against the first piston, compress the spring that moves the second piston, and initiate a pressure wave in the working hydraulic fluid.   
     
     
         10 . The method of  claim 8 , wherein the hydraulic motor drives a first wheel, the method further comprising using the pressure wave to drive a second hydraulic motor and a second wheel, a third hydraulic motor and a third wheel, and a fourth hydraulic motor and a fourth wheel. 
     
     
         11 . The method of  claim 8 , wherein the dilating hydraulic fluid has a first coefficient of thermal expansion and the working hydraulic fluid has a second coefficient of thermal expansion that is lower than the first coefficient of thermal expansion. 
     
     
         12 . The method of  claim 8 , further comprising using the pressure wave in the working hydraulic fluid to provide energy to a hydraulic accumulator. 
     
     
         13 . The method of  claim 8 , further comprising using the pressure wave to provide energy to an electrical energy generator. 
     
     
         14 . The method of  claim 8 , further comprising using the pressure wave to move a piston within a hydraulic cylinder. 
     
     
         15 . The method of  claim 14 , wherein moving the piston within the hydraulic cylinder includes compressing a spring within the hydraulic cylinder. 
     
     
         16 . The method of  claim 15 , wherein moving the piston within the hydraulic cylinder and compressing the spring within the hydraulic cylinder includes oscillating the piston and the spring within the hydraulic cylinder. 
     
     
         17 . The method of  claim 16 , wherein oscillating the piston and the spring within the hydraulic cylinder includes oscillating the piston and the spring in resonance within the hydraulic cylinder. 
     
     
         18 . The method of  claim 15 , wherein the piston separates the dilating hydraulic fluid from the working hydraulic fluid. 
     
     
         19 . An energy conversion system, comprising:
 a hydraulic tank;   a hydraulic pump hydraulically coupled to the hydraulic tank;   a check valve hydraulically coupled to the hydraulic pump;   a 2/2 hydraulic valve hydraulically coupled to the check valve and a first hydraulic cylinder, wherein the first hydraulic cylinder houses a first piston and a first spring;   a first directional control valve, a second directional control valve, and a third directional control valve, wherein the first directional control valve is hydraulically coupled to the 2/2 hydraulic valve and the first hydraulic cylinder, and wherein the first directional control valve is further hydraulically coupled to a second directional control valve and a third directional control valve, wherein the second directional control valve is hydraulically coupled to a second hydraulic cylinder, the second hydraulic cylinder housing a second piston that supports a weight, and wherein the third directional control valve hydraulically coupled to a hydraulic motor;   a third hydraulic cylinder hydraulically coupled to the third directional control valve and the hydraulic motor, wherein the third hydraulic cylinder houses a third piston and a second spring,   a rod mechanically coupled to the third piston, the rod mechanically coupled by a rotational joint to a lever, and   a wheel mechanically coupled to the lever, wherein the wheel is further mechanically coupled to a shaft.   
     
     
         20 . The system of  claim 19 , wherein the hydraulic motor drives a first wheel, the method further comprising using the pressure wave to drive a second hydraulic motor and a second wheel, a third hydraulic motor and a third wheel, and a fourth hydraulic motor and a fourth wheel. 
     
     
         21 . The system of  claim 19 , wherein the dilating hydraulic fluid has a first coefficient of thermal expansion and the working hydraulic fluid has a second coefficient of thermal expansion that is lower than the first coefficient of thermal expansion. 
     
     
         22 . The system of  claim 19 , further comprising a pressure wave generator that uses pressure waves in the working hydraulic fluid to provide energy to a hydraulic accumulator. 
     
     
         23 . The system of  claim 19 , further comprising a pressure wave generator that uses pressure waves to provide energy to an electrical energy generator. 
     
     
         24 . The system of  claim 19 , further comprising a pressure wave generator that uses pressure waves to move a piston within a hydraulic cylinder. 
     
     
         25 . The system of  claim 24 , wherein the hydraulic cylinder further includes a spring, and moving the piston within the hydraulic cylinder compresses the spring within the hydraulic cylinder. 
     
     
         26 . The system of  claim 25 , wherein compressing the spring within the hydraulic cylinder causes oscillation of the piston and the spring within the hydraulic cylinder. 
     
     
         27 . The system of  claim 26 , wherein oscillation of the piston and the spring within the hydraulic cylinder causes oscillation the piston and the spring in resonance within the hydraulic cylinder. 
     
     
         28 . The system of  claim 24 , wherein the piston separates the dilating hydraulic fluid from the working hydraulic fluid.