Patent Description:
Generators (e.g., diesel generators, gas turbine engines, etc.) are used to generate power. Such systems may be used to power cooling units to generate cooled fluid (e.g., air, gases, or liquids) for a designated space (e.g., building, aircraft cabin, etc.) or for other purposes (e.g., cooling fluids to cool electronics or other components and/or systems). These generators conventionally burn fuels, such as diesel or jet fuel, to generate heated air that drives turbines and compressors to move air through the generator and spin a shaft, which may be operably arranged to generate power.

Alternative power generation systems may be operated using supercritical CO<NUM>. Power generation cycles with a supercritical CO<NUM> bottoming cycle are more efficient than conventional approaches that can decrease fuel burn and are financially attractive. Such systems can represent a potential solution for aerospace applications where space and weight are limiting and in forward operating bases where agility and compactness are paramount. Improved supercritical CO<NUM> systems may be desirable to improve efficiencies and utility of such power generation systems.

<CIT> describes a cooling system for an aircraft that includes an air intake, an expansion device, and an evaporator. A first heat exchanger receives air passing into the air intake when the aircraft is operating at elevation, and receives the refrigerant from a first compressor at a first pressure.

<CIT> describes a supercritical carbon dioxide power generation system including a regenerator, a turbine, a heat recoverer, a condenser, a compressor an expansion valve, a flash tank, a heat exchanger, and an ejector, and may utilize waste heat of the supercritical carbon dioxide power generation system. <CIT> describes a method and aircraft for providing bleed air to environmental control systems of an aircraft using a gas turbine engine.

<CIT> describes a system comprising: an ejector for receiving a gaseous feed stream and a pressurized fluid stream and for providing a mix thereof at an outlet of the ejector.

<CIT> describes a method for operating a closed loop regenerative thermodynamic power generation cycle system.

Subject of the invention is a power and cooling system with the features of claim <NUM>.

According to an aspect, there is provided power and cooling systems. The power and cooling systems include a drive system having a drive shaft with a turbine, a first compressor, and a second compressor each operably coupled to the drive shaft. A power generation unit defines a power generation flow path of a primary working fluid that is expanded within the turbine of the drive system and compressed within the first compressor and the second compressor in a closed-loop cycle. The power generation unit includes a generator configured to generate electrical power, the generator driven by the drive shaft of the drive system and a heat source configured to heat the primary working fluid prior to injection into the turbine. A cooled fluid generation unit defines a cooled fluid flow path of a portion of the primary working fluid that is extracted from the second compressor and compressed within the first compressor. The cooled fluid generation unit includes an ejector downstream of the second compressor along the cooled fluid flow path and a separator arranged downstream of the ejector and configured to separate liquid and gaseous portions of the primary working fluid, wherein the gaseous portion is directed to the first compressor and the liquid portion is directed to an evaporator heat exchanger to generate a cooled fluid, wherein the primary working fluid is directed to the ejector after passing through the evaporator heat exchanger.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the heat source is a combustion system and waste heat from the combustion system is passed through a hot gas-heat exchanger that is configured to heat the primary working fluid upstream of the turbine along the power generation flow path.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the combustion system is a gas turbine engine.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the gas turbine engine is configured to generate propulsive force for flight of an aircraft.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the combustion system is a diesel engine.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the heat source is a burner configured to heat the primary working fluid.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the primary working fluid is supercritical CO<NUM>.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the cooled fluid generation unit comprises a condenser heat exchanger arranged between the second compressor and the ejector along the cooled fluid flow path.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the condenser heat exchanger receives ambient air as a secondary working fluid to cool the primary working fluid prior to entry into the ejector.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the cooled fluid generation unit comprises an expansion valve arranged between the separator and the evaporator heat exchanger.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the power generation unit comprises a recuperator heat exchanger arranged downstream from the turbine along the power generation flow path, wherein the recuperator heat exchanger is configured to receive two separate flows of the primary working fluid to enable heat exchange therebetween.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the power generation system comprises a heat rejection heat exchanger arranged downstream of the recuperator heat exchanger and upstream of the first condenser.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include a heat rejection heat exchanger arranged between the first compressor and the second compressor and configured to cool the primary working fluid.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include a blower configured to direct air into the heat rejection heat exchanger, wherein the blower is powered by the generator.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the cooled fluid is cooled air that is supplied to a passenger cabin of an aircraft.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the cooled fluid is cooled air that is supplied to a room of a building.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include an additional compressor arranged between the first compressor and the second compressor along the drive shaft.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the primary working fluid of the cooled fluid generation unit is merged with the primary working fluid of the power generation unit within the first compressor.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the primary working fluid of the cooled fluid generation unit is merged with the primary working fluid of the power generation unit within the additional compressor.

In addition to one or more of the features described herein, or as an alternative, further embodiments of the power and cooling systems may include that the portion of the primary working fluid that is extracted to the cooled fluid generation unit comprises no more than <NUM>% of the primary working fluid within the power and cooling system.

Power generation cycles with a supercritical fluid bottoming cycle, as described herein, are more efficient than conventional approaches for generating power (e.g., diesel and/or gas turbines). The supercritical fluid may be, for example and without limitation, carbon dioxide (sCO<NUM>), helium, nitrogen, noble gases, water, or other fluids, and mixtures thereof. These systems can decrease fuel burn and may be financially attractive due to lower operating costs, less fuel consumption, etc. The systems described herein may be implemented in, for example and without limitation, aerospace applications where space and weight are limiting and in forward operating bases where agility and compactness are paramount.

Embodiments of the present invention enable a dual purpose system, providing both power and cooling. As such, embodiments of the present invention may enable replacing multiple other components with a single, integrated system, and provide combined system benefits. Some embodiments of the present invention are directed to power generation and cooling systems that are configured to run off waste heat, which is essentially free energy to produce the power and the cooling. In some embodiments, the power generation and cooling systems may be configured to be run off or operated using a burner to produce heat to drive the systems described herein. Advantageously, embodiments of the present invention employ a zero ozone depletion potential (ODP) working fluid (i.e., CO<NUM>).

Waste heat from diesel generators or gas turbine engines have a high temperature exhaust that is expunged out of the exhaust and is essentially lost energy. Embodiments of the present invention are directed to capturing this waste heat and converting it to generate power and cooling using a power and cooling system (e.g., power and cooling unit (PCU)) that employs a closed-loop supercritical fluid (e.g., CO<NUM> (sCO<NUM>)) to generate both power and cooled fluid for distribution to a space, environment, or other systems (e.g., as a cooling fluid within such systems).

Referring now to <FIG>, a schematic illustration of a power and cooling system <NUM> in accordance with an embodiment of the present invention is shown. The power and cooling system <NUM> is configured to generate power and generate cooled fluid for cooling a space, environment, or components. The cooled fluid may be air, gases, liquids, or other fluids which may be distributed to various locations or passes through cooling systems of components or systems. The power and cooling system <NUM> has a power generation unit <NUM> and a cooled fluid generation unit <NUM>, which are each operably connected to a central drive system <NUM>. The power and cooling system <NUM> is configured to operate in a substantially closed-loop configuration using a supercritical primary working fluid (e.g., sCO<NUM>). The driving force of the closed-loop system is capture and use of waste heat <NUM> from a combustion system <NUM>. The combustion system <NUM> may be a gas turbine engine (e.g., onboard an aircraft), a gas furnace, gas combustor, burner, or the like. The combustion system <NUM> generates heated air or combustion output during operation. This heated air can be used to cause a change in the primary working fluid of the power and cooling system <NUM>, such as a phase change in a working fluid or increase a temperature of a supercritical fluid.

The drive system <NUM>, of this illustrative embodiment, includes a drive shaft <NUM>, a turbine <NUM>, a first compressor <NUM>, and a second compressor <NUM>. The turbine <NUM> and the first and second compressors <NUM>, <NUM> are operably coupled to the drive shaft <NUM>. Rotation of the turbine <NUM> will cause rotation of the drive shaft <NUM>, which in turn drives rotation of the first and second compressors <NUM>, <NUM>. The turbine <NUM> and the compressors <NUM>, <NUM> form portions of flow paths associated with the power generation unit <NUM> and the cooled fluid generation unit <NUM>. The turbine <NUM> is configured to expand the primary working fluid and extract work therefrom. The compressors <NUM>, <NUM> are configured to compress the primary working fluid.

The power generation unit <NUM> includes a hot gas-heat exchanger <NUM> that is configured to receive waste heat <NUM> from the combustion system <NUM>. The waste heat <NUM> is used to heat the primary working fluid within the hot gas-heat exchanger <NUM>. The heated primary working fluid is then passed along a power generation flow path <NUM> to the turbine <NUM>. The primary working fluid is then expanded within the turbine <NUM> and work is extracted therefrom to drive rotation of the drive shaft <NUM>. The hot and expanded primary working fluid is then directed to a recuperator heat exchanger <NUM>, where the primary working fluid is cooled. The cooled primary working fluid is then directed through a first heat rejection heat exchanger <NUM>, into and through the first compressor <NUM>, through a second heat rejection heat exchanger <NUM>, into and through the second compressor <NUM>, back through the recuperator heat exchanger <NUM>, and finally back to the hot gas-heat exchanger <NUM>. The first and second heat rejection heat exchangers <NUM>, <NUM> may employ air or other first secondary working fluid <NUM> to pick up heat from the primary working fluid. As a result of the compressors <NUM>, <NUM> and the heat exchangers <NUM>, <NUM>, <NUM>, the primary working fluid is relatively cool when it enters the hot gas-heat exchanger <NUM> during the closed-loop cycle of the power generation unit <NUM>.

The closed-loop cycle of the power generation unit <NUM> drives rotation of the turbine <NUM>. As noted, the turbine <NUM> drives rotation of the drive shaft <NUM>. The drive shaft <NUM> may be coupled to a generator <NUM>. The generator <NUM> may be configured to generate electrical power, as will be appreciated by those of skill in the art (e.g., rotation of a rotor relative to a stator). As such, the power generation unit <NUM> is configured to generate usable electrical power.

The cooled fluid generation unit <NUM> is also operably coupled to the drive system <NUM>. A cooled fluid flow path <NUM> passes through each of the first compressor <NUM> and the second compressor <NUM> and the second heat rejection heat exchanger <NUM> of the power generation unit <NUM>. At the second compressor <NUM> of the drive system <NUM>, the flow paths <NUM>, <NUM> are split so that a portion of the primary working fluid is directed into the cooled fluid flow path <NUM>. The relatively cool and compressed primary working fluid is directed into a condenser heat exchanger <NUM>, which may employ air as a secondary working fluid <NUM>, to condense the primary working fluid into a liquid state.

The condensed primary working fluid is then directed into an ejector <NUM>. Within the ejector <NUM>, the liquid primary working fluid is mixed with a recycled portion of the primary working fluid and directed into a separator <NUM>. At the separator <NUM>, the primary working fluid is separated into a liquid stream that is sent to an evaporator heat exchanger <NUM> and a gaseous stream that is sent to the first compressor <NUM> of the drive system <NUM>. An expansion valve <NUM> may be arranged between the separator <NUM> and the evaporator heat exchanger <NUM>. Within the evaporator heat exchanger <NUM>, ambient air <NUM> is cooled by the liquid primary working fluid and directed to a space <NUM> to receive the cooled air. In other embodiments, a cooling fluid (e.g., liquid) may be cooled within the evaporator heat exchanger <NUM> and then supplied to another system to provide cooling thereto. After passing through the evaporator heat exchanger <NUM>, the liquid primary working fluid may be heated sufficiently to transition back to a gaseous state, and this gaseous primary working fluid is directed back to the ejector <NUM> to be mixed with the liquid primary working fluid received from the condenser heat exchanger <NUM>. In operation, the ejector <NUM> functions effective as a pump to raise the pressure of one fluid stream using energy from another higher pressure fluid stream, and thus operates as a work recovery device or component within the system.

The gaseous portion of the primary working fluid that is separated at the separator <NUM> is mixed with the primary working fluid of the power generation unit <NUM> within the first compressor <NUM> of the drive system <NUM>. This mixed or combined primary working fluid is compressed in the first compressor <NUM>, passed through the second heat rejection heat exchanger <NUM>, and into the second compressor <NUM>, wherein the two streams of primary working fluid are split for distribution to the power generation unit <NUM> and the cooled fluid generation unit <NUM>.

In operation, combustion products from the combustion system <NUM> (e.g., gas turbine engine exhaust, exhaust from diesel engine, etc.) are used to heat the supercritical primary working fluid cycle to produce power along the power generation flow path <NUM> of the power generation unit <NUM>. The power generation unit <NUM> is a supercritical working fluid recuperated Brayton cycle that produces power by converting waste heat into power in a turbogenerator (e.g., turbine <NUM> and generator <NUM>). To accomplish this, high pressure primary working fluid (e.g., sCO<NUM>) is heated at the waste-heat heat exchanger <NUM>, expanded to low pressure across the turbine <NUM> to make power, and cooled in the recuperator heat exchanger <NUM>. As illustrated, the recuperator heat exchanger <NUM> uses the primary working fluid as both fluids therein, enabling heat exchanger between two streams of the primary working fluid. Heat is rejected at the heat rejection heat exchangers <NUM>, <NUM> as the primary working fluid is compressed back to high pressure in the compressors <NUM>, <NUM>.

The split stream integration with the cooled fluid generation system <NUM> is enabled by splitting the outlet/output of the second compressor <NUM> a coolant stream along the cooled fluid flow path <NUM>, where the primary working fluid is cooled and expanded for use in cooling and a power generation stream along the power generation flow path <NUM> that completes the power cycle after being heated in the recuperator <NUM>.

The cooling cycle along the cooled fluid flow path <NUM> operates by extracting a small amount of the primary working fluid from the second compressor <NUM>. For example, in some non-limiting embodiments up to <NUM>% of the total compressor flow may be used for the cooling cycle, although other percentages of total compressor flow may be used without departing from the scope of the present disclsoure. The high-pressure primary working fluid extracted from the second compressor <NUM> is cooled in the condenser heat exchanger <NUM> and then expanded through the ejector <NUM>. In the ejector <NUM>, a low-pressure stream (from the evaporator heat exchanger <NUM>) is mixed and entrained to produce an intermediate pressure stream entering the separator <NUM>. Example, non-limiting values for pressures in a system in accordance with the present disclosure may be about ~<NUM> MPa for motive, ~3MPa for suction, and ~<NUM> Mpa for intermediate pressure. It will be appreciated that these may be adjusted or move up or down according to operating conditions and the selected working fluid. From the separator <NUM>, the liquid portion of the primary working fluid is further expanded in the expansion valve <NUM> and directed to the evaporator heat exchanger <NUM> for very low temperature cooling, and a vapor portion of the primary working fluid is directed to the first compressor <NUM> for re-integration with the power cycle.

In one non-limiting example of operation of the cooled fluid generation unit <NUM>, the ambient air <NUM> may have a relatively high temperature of about <NUM> °F (about <NUM>). As the ambient air passes through the evaporator heat exchanger <NUM>, the primary working fluid will extract heat from the air, thus cooling the air. As a result, the air supplied to the space <NUM> may have a temperature of about <NUM> °F (about <NUM>. In other embodiments, rather than cooling ambient air, the cooled fluid generation units of the present disclosure may be configured to cool other gases or liquids which can be used for air conditioning a space, used for cooling components (e.g., electronics), or otherwise distributed such that the cooled fluid may be used to provide cooling and/or to extract heat.

Turning now to <FIG>, schematic plots of an example of aspects of operation of a power and cooling system in accordance with an embodiment of the present invention are shown. Plot <NUM> of <FIG> illustrates entropy as a function of temperature for the split cycles of a power and cooling system in accordance with an embodiment of the present invention.

Line <NUM> represents aspects of the power generation unit of the system and line <NUM> represents aspects of the cooled fluid generation unit of the system. Plot <NUM> of <FIG> illustrates enthalpy as a function of pressure, with line <NUM> representing the working fluid along the flow path of the cooled fluid generation unit. Line <NUM> of plot <NUM> represents a traditional transcritical system. Region <NUM> represents the improved, and reduced compressor work and region <NUM> represents the increased cooling capacity, each of which are enabled through use of the ejector-based cooled fluid generation unit, as compared to a conventional system.

Due to the inclusion of the ejector within the cooled fluid generation unit, the low pumping power associated with supercritical working fluids combined with expansion work recovery using the ejector can minimize compression work to deliver high coefficient of performance (COP) cooling. The cooling cycle operates by extracting a small amount of the working fluid stream from the second compressor and passing this extracted portion through the condenser heat exchanger that is cooled with ambient air. The cold high-pressure working fluid is then expanded through the ejector, mixing and entraining a low pressure stream to produce an intermediate pressure stream entering the separator. From the separator, liquid is expanded and directed to the evaporator for very low temperature cooling, and vapor is directed to the compressor for reintegration with the power cycle.

In conventional combined diesel engine-generator machinery (gensets), the engine has often been optimized for transport applications and does not align with the optimal speed for the generator. A compromise is made between the performance of the generator and/or engine at off-design speed or efficiency, resulting in a combined efficiency ~<NUM>%. Moreover, cooling is performed separately in a conventional motor driven vapor compression cycle, which requires electricity as an input and uses a high global warming potential (GWP) and high specific volume refrigerant.

In contrast, the power and cooling systems of the present disclosure are configured to generator power and cooling directly and simultaneously from a waste heat stream. Both power and cooling cycles of the power and cooling systems capitalize on the low compression work of supercritical fluids (e.g., sCO<NUM>) in a recuperated Brayton cycle and transcritical fluids (e.g., tCO<NUM>) in the refrigeration cycle to produce power and cooling at high thermal efficiency and high COP, respectively. That is, in some embodiments of the present invention, the power and cooling systems includes a supercritical unit (i.e., the power generation unit) and a transcritical unit (e.g., the cooled fluid generation unit).

The heat exchangers of the power and cooling systems of the present disclosure may have minimal weight and volume for the desired output power and cooling. As described, the power and cooling systems employ waste heat capture and heat rejection, thus the major contributor to weight and volume will be the system heat exchangers. In accordance with one non-limiting example of a power and cooling system in accordance with the present disclosure, a volumetric cooling and power density of <NUM> kW/ft<NUM> and <NUM> kW/kg, respectively, may be provided, which is approximately a <NUM>% reduction on a state-of-the-art HVAC and auxiliary power unit (APU) systems.

Supercritical working fluids, such as CO<NUM>, are extremely dense, which ensures compact but also high-speed turbomachinery, rotating at ~<NUM>,<NUM> RPM. In accordance with embodiments of the present invention, a compressor efficiency of approximately <NUM>% may be achieved. In accordance with one non-limiting example, the turbo-generator compressor may employ a direct drive generator operating at high speeds with a permanent magnet (PM) to enable compact generators that are approximately <NUM>% efficient and extremely power dense (e.g., <NUM> kW/kg). In contrast to the diesel gensets (conventional systems), the generator (e.g., generator <NUM>) can be tailored to the power cycle for optimal speed and capacity for optimal performance. The ejector enhanced transcritical working fluid cycle (e.g., cooled fluid generation unit <NUM>), in accordance with one non-limiting example, can achieve an approximate COP of approximately <NUM>. The flow splitting of the high pressure supercritical primary working fluid stream performs cooling with no fuel-to-electric and electric-to-cooling conversion losses, thereby delivering combined system efficiency benefits. The combined cycle can achieve compounding benefits due to downsizing of the generator to handle only the power cycle load, which reduces size and weight while also enabling high speed turbomachinery and compact generator configurations. As a result, embodiments of the present invention may provide for a compact and portable system with a highly efficient and manageable option that addresses power and cooling needs in a low weight, small footprint that will enable increased operational agility.

The cycle of the power and cooling systems described herein may capitalize on low compression work of supercritical primary working fluids to produce power and cooling at high thermal efficiency (<NUM>% vs. <NUM>%) and high COP (<NUM> vs. <NUM>). In some embodiments and configurations, due to the combined nature of the power generation and fluid cooling in a single system, the systems may occupy significantly smaller footprints (<<NUM>%) as compared to traditional systems. Further, through the flow splitting of the primary working fluid stream, the cooling may be achieved with no fuel-to-electric and electric-to-cooling conversion losses, thus delivering combined system benefits. Such benefits can provide compounding benefits enabling downsizing of the generator to handle only the power cycle load. Turning now to <FIG>, a schematic illustration of a power and cooling system <NUM> in accordance with an embodiment of the present invention is shown. The power and cooling system <NUM> is configured to generate power and generate cooled fluid for cooling a space, environment, or other components/systems. The power and cooling system <NUM> is substantially similar to that described above, having a power generation unit <NUM> and a cooled fluid generation unit <NUM>, which are each operably connected to a central drive system <NUM>. The power and cooling system <NUM> is configured to operate in a substantially closed-loop configuration using a supercritical primary working fluid (e.g., sCO<NUM>). The primary difference between the power and cooling system <NUM> and the power and cooling system <NUM> of <FIG>, is the motive or heating source. In the embodiment of <FIG>, the heat is supplied from waste heat from a combustion system that may be configured for an alternative purpose (e.g., gas turbine engine onboard an aircraft for propulsive flight). However, in this alternative embodiment, the waste heat portion may be replaced by a dedicated burner or heater <NUM>. In this case, the heater <NUM> may be a combustion heater (e.g., burner), electric heater, or other heat source, as will be appreciated by those of skill in the art.

In operation, the power and cooling system <NUM> operates substantially similarly as that described above. A power generation flow path <NUM> of a primary working fluid is used to drive a turbine <NUM> which can drive operation of a generator <NUM>, with a substantially closed-loop cycle of the primary working fluid. A portion of the primary working fluid may be split to flow through a cooled fluid flow path <NUM> to generate cooled fluid (e.g., air) to be supplied to a space <NUM>, similar to that described above, including use of an ejector <NUM>.

In this embodiment, one or more fans or blowers <NUM> are arranged to direct the air used as a secondary working fluid at various locations through the power and cooling system <NUM>. For example, the blowers <NUM> may be used to pass ambient air through one or more heat rejection heat exchanger <NUM>, a condenser heat exchanger <NUM>, and/or an evaporator heat exchanger <NUM>. The blowers <NUM> may be electrically powered with electrical power supplied from the generator <NUM> of the power and cooling system <NUM>. These blowers <NUM> may also be implemented within the configuration of <FIG>, and thus the present disclosed configuration is not to be limiting, but rather is an example configuration.

Although illustratively shown in both power and cooling systems <NUM>, <NUM>, a first compressor <NUM> and a second compressor <NUM> are operably coupled to the drive shaft <NUM>. However, in other configurations, more than two compressors may be incorporated, and, optionally, additional heat rejection heat exchangers may be incorporated as well.

For example, turning now to <FIG>, a schematic illustration of a drive system <NUM> of a power and cooling system in accordance with an embodiment of the present invention is shown. The drive system <NUM> includes a drive shaft <NUM> with a turbine <NUM>, a first compressor <NUM>, a second compressor <NUM>, and a third compressor <NUM> operably connected thereto. The drive shaft <NUM> may be operably configured to drive a generator, as shown and described above. The turbine <NUM> and compressors <NUM>, <NUM>, <NUM> are arranged along flow paths of a primary working fluid, similar to that described above. For example, a power generation flow path <NUM> is arranged to carry a primary working fluid through a power generation unit <NUM>. Similarly, a cooled fluid flow path <NUM> is arranged to carry a portion of the primary working fluid through a cooled fluid generation unit <NUM>. The two flow paths <NUM>, <NUM> are merged or combine at the first compressor <NUM>, and the combined flow <NUM> flows through a first heat rejection heat exchanger <NUM> (e.g., similar to second heat rejection heat exchanger <NUM> of <FIG>). The combined flow <NUM> is directed into the second compressor <NUM>, through a second heat rejection heat exchanger <NUM>, and into the third compressor <NUM>. At the third compressor <NUM> a portion of the primary working fluid is extracted and directed along the cooled fluid flow path <NUM> for use within the cooled fluid generation unit <NUM>. The remainder of the primary working fluid is passed to the power generation unit <NUM>.

In this embodiment, the portion extracted for the cooled fluid generation unit is extracted at the last compressor in the series along the drive shaft. However, such extraction point is not to be limiting. For example, in some embodiments, the portion extracted for the cooled fluid generation unit may be pulled from the second compressor, with the remainder being passed through the additional (optional) heat rejection heat exchanger, and through the third compressor for the power generation unit. Further, in other embodiments, more compressors and/or heat rejection heat exchangers may be employed. Moreover, in some embodiments, one or more of the heat rejection heat exchangers may be omitted from between adjacent compressors along the flow path. The heat rejection heat exchangers and compressors may be provided and arranged to achieve desired temperature and/or pressure requirements for operation of both of the power generation unit and the cooled fluid generation unit. Additionally, the point of rejoining the two separate flows is not required to be at the first compressor in the series. For example, in another non-limiting configuration, the flow from the power generation unit may pass through a compressor prior to the merging of the two flows, which are then passed through a downstream compressor (or vice versa where the cooled fluid generation unit flow is compressed prior to the merging). As such, those of skill in the art will appreciate that different configurations are possible without departing from the scope of the present invention.

Claim 1:
A power and cooling system (<NUM>; <NUM>) comprising
a drive system (<NUM>; <NUM>; <NUM>) having a drive shaft with a turbine (<NUM>; <NUM>; <NUM>), a first compressor (<NUM>; <NUM>), and a second compressor (<NUM>; <NUM>) each operably coupled to the drive shaft;
a power generation unit (<NUM>; <NUM>; <NUM>) defining a power generation flow path (<NUM>; <NUM>; <NUM>) of a primary working fluid that is expanded within the turbine (<NUM>; <NUM>; <NUM>) of the drive system (<NUM>; <NUM>; <NUM>) and compressed within the first compressor (<NUM>; <NUM>) and the second compressor (<NUM>; <NUM>) in a closed-loop cycle, the power generation unit (<NUM>; <NUM>; <NUM>) comprising:
a generator (<NUM>; <NUM>) configured to generate electrical power, the generator (<NUM>; <NUM>) driven by the drive shaft of the drive system (<NUM>; <NUM>; <NUM>); and
a heat source configured to heat the primary working fluid prior to injection into the turbine (<NUM>; <NUM>; <NUM>); and
a cooled fluid generation unit (<NUM>; <NUM>; <NUM>) defining a cooled fluid flow path of a portion of the primary working fluid that is extracted from the second compressor (<NUM>; <NUM>) and compressed within the first compressor (<NUM>; <NUM>), the cooled fluid generation unit (<NUM>; <NUM>; <NUM>) comprising:
an ejector (<NUM>; <NUM>) downstream of the second compressor (<NUM>; <NUM>) along the cooled fluid flow path; and
a separator (<NUM>) arranged downstream of the ejector (<NUM>; <NUM>) and configured to separate liquid and gaseous portions of the primary working fluid, wherein the gaseous portion is directed to the first compressor (<NUM>; <NUM>) and the liquid portion is directed to an evaporator heat exchanger (<NUM>; <NUM>) to generate a cooled fluid, wherein the primary working fluid is directed to the ejector (<NUM>; <NUM>) after passing through the evaporator heat exchanger (<NUM>; <NUM>).