Patent Application
20100283262
This disclosure relates generally to an energy recovery and cooling system for a hybrid machine. In particular, the disclosure relates to a system for successively recovering and using thermal energy from a plurality of machine components on a hybrid machine.
As the cost of traditional fossil fuels rise, many industries are devoting more attention and resources to reducing fuel consumption. One common approach is to employ a “hybrid” power system in a machine such as a construction machine or passenger vehicle. For purposes of this disclosure, a hybrid system may be generally defined as a power system that includes an energy storage device, such as a battery, in addition to fuel storage for an internal combustion engine.
In normal operation of a machine, system inefficiencies create heat that must be dissipated by a cooling system. Excessive heat can damage sensitive components such as electronic equipment. In an electric hybrid system, heat is generated from machine components such as the battery, power electronics, engine, and exhaust system. Further, these machine components do not usually operate at the same temperature, and each machine component may tolerate heat build up differently. One or more of the machine components may require a cooling system to keep the component within its allowable operating temperature. Such cooling systems consume energy and therefore may increase fuel consumption. In addition, waste heat is often vented to the atmosphere through an exhaust pipe or other means, which represents a lost opportunity to use the heat for useful work necessary to power the machine.
Various methods and systems exist in the art to utilize was heat to increase the energy conversion efficiency of an overall system. For example, U.S. Pat. No. 5,191,766 to Vines discloses an internal combustion/steam engine that utilizes waste heat to generate steam under pressure to augment the power produced by the fuel burn of the engine. The steam may serve to power an engine cooling system.
While the system disclosed in Vines may succeed in increasing overall system efficiency, it does not allow for cooling of other additional system components, and does not take into consideration that different machine components may operate at different optimal temperatures, each of which may need to be sufficiently cooled to such different operating temperatures.
The present disclosure is directed to overcoming or mitigating one or more of the problems set forth above.
In one embodiment of the disclosure, an apparatus includes a fluid pump operably connected to a condenser and a fluid path operably connected to the fluid pump and to a turbine. The fluid path is in thermal communication with a first machine component and then a second machine component, and the first machine component has a static operating temperature equal to or lower than the second machine component.
In another embodiment of the disclosure, a cooling system for a machine is provided. The cooling system includes a fluid pump for pumping a fluid along a fluid path. The fluid is in thermal communication with first and second machine components such that, along the fluid path, the second machine component is downstream from the first machine component and has a static operating temperature equal to or higher than the first machine component. The system also includes a turbine oriented downstream from the second machine component along the fluid path and configured for actuation by the fluid. The system further includes a condenser oriented downstream from the turbine and upstream from the fluid pump along the fluid path, and an internal combustion engine operably connected to a drivetrain for providing propulsion to the machine.
In another embodiment of the disclosure, a method for cooling machine components is provided. The method includes the step of pumping fluid along a fluid path in thermal communication with a first machine component. The method further includes the step of pumping fluid along the fluid path in thermal communication with a second machine component, where the second machine component has a static operating temperature equal to or greater than the static operating temperature of the first machine component. The method also includes the step of employing the fluid to power a turbine operably connected with the fluid, and condensing the fluid for reuse along the fluid path.
Apparatus 10 includes a fluid pump 12, a fluid path 14, and a plurality of machine components. Fluid pump 12 pumps a fluid along fluid path 14. The fluid may be any type of common fluid used for cooling or for powering a turbine, such as water/steam, air, or common gases. Fluid is pumped by fluid pump 12 along fluid path 14 to exchange thermal energy with a plurality of machine components. Fluid path 14 may be composed of a variety and combination of structures to allow circulation of fluid. For example, fluid path 14 may include hoses, channels, or other structure components designed to carry fluid. Heat exchangers, insulators, and similar components may also help optimize and appropriately allow thermal communication between the fluid path 14 and a plurality of machine components.
In
If first machine component 16 is operating at a higher operating temperature than the temperature of the fluid, thermal energy may be transferred from first machine component 16 to the fluid as the fluid is pumped along fluid path 14.
The fluid may then proceed through fluid path 14 to exchange thermal energy with more machine components. The machine components along fluid path 14 in the direction of fluid flow may be considered “downstream” from earlier machine components. In
For example, in the embodiment shown in
As used herein, the term “normal static operating temperature” refers to the general operating temperature of the machine component during regular operation of the machine. Of course, in operation of the machine, various machine components may, for myriad various reasons, exceed or fall below the normal static operating temperature of that machine component. For example, a machine component may cease to operate or may overheat, causing its operating temperature at a given time to fall outside of its normal static operating temperature. These variations can be appreciated by one of skill in the art not to alter the scope or nature of the disclosure herein. For purposes of this disclosure, the more important attribute is that under normal operation of the machine, a plurality of machine components may exist that have different normal operating temperatures. This allows the fluid passing along fluid path 14 to successively gain thermal energy from the successive machine components as the fluid passes.
In the example of
Alternatively, power component 26 may be a radiator fan. This alternative configuration may be advantageous because, as the plurality of machine components generates additional heat, more power may be provided to turbine 24, which in turn, may provide more power to the radiator fan (increasing the speed of the fan) to increase cooling. Thus this configuration is dynamically adaptable to adjust to variations of the heat generated by the plurality of machine components.
The present disclosure provides an advantageous apparatus and system for energy recovery and cooling in a hybrid machine. The disclosure may help improve the fuel economy of a machine by recovering additional energy and putting recovered energy to effective use to power machine systems, while simultaneously cooling a plurality of machine components.
Other embodiments, features, aspects, and principles of the disclosed examples will be apparent to those skilled in the art and may be implemented in various environments and systems.
