| 摘要 |
A closed-loop Brayton cycle (topping system) takes in heat energy at very high temperatures and rejects heat energy as input heat energy to a closed-loop Rankine cycle (base system). Heat energy input to the base system comes partially or solely from the high-temperature topping system. Materials having high strength at high temperatures enable the topping system to extract significant mechanical energy from thermal energy contained in high temperature working fluid and discharge waste energy from the topping system to the base system at temperatures sufficiently high to be fully useable input to the base system. In the preferred embodiment, closed-loop Brayton-cycle operates at maximum temperatures greatly in excess of maximum temperatures of a conventional steam Rankine-cycle. Consequently, a high-temperature closed-loop Brayton cycle topping system of significant output and efficiency can act as an addition to a conventional steam power-generating station. Carbon-carbon is used to make the Brayton-cycle topping system's turbine rotor and piping for ducting the working fluid between a "firebox" and the Brayton-cycle topping system's turbine. An inert gas working fluid is used to provide a nonoxidizing environment for the carbon-carbon. A shielding-cooling-insulating system provides a structural cooling loop which permits use of conventional metal for containment and ducting of high-temperature working fluids. In a system heated by fossil fuel, tubular ceramic heat exchanger elements capable of withstanding high temperatures are used. All energy put into the topping system is productively utilized either in the topping system as shaft power output or by the base system as input. |
