Patent Description:
A typical commercial aircraft includes at least several nonintegrated pressurization systems configured to provide temperature control to various regions of the aircraft. For example, an aircraft environmental control system primarily provides heating and cooling for the aircraft cabin area. In addition, a galley chiller system is dedicated to refrigerating the food carts in the galleys located throughout the aircraft. Since each system has a significant weight and power requirement, the overall efficiency of the aircraft is affected by these nonintegrated systems.

One or more of these pressurization systems may rely on ram or fresh air to condition, i.e., to cool or heat another medium. However, in applications where the aircraft is travelling at supersonic speeds, the temperature of the ram air may be too high to effectively remove heat from another load.

<CIT> discloses a cabin pressurizing system comprising first duct means, second duct means, first ram means, air compressor means, means for cooling compressed air before injection into the cabin, and means that is the sole source of cabin pressurizing drive power which includes a first air turbine, a second air turbine, and second ram means. The means for compressing air to supply the pressure cabin are driven by power extracted from the cabin discharge stream and from the second ram means.

<CIT> discloses a cabin air supply means comprising an air intake means which in use is supplied with kinetically-heated air and which affords first and second air streams, a main air turbine connected to the air intake means to receive and to be driven by the first air stream, an air compressor drivingly connected to the air turbine and receiving the second air stream, a heat exchanger having a first flow path connected to receive air compressed in the compressor and a second flow path which in use is connected to receive air flowing from the aircraft cabin thereby to cool the air flowing in the first flow path, and an expansion turbine connected. to receive air from the outlet of the first flow path through the heat exchanger, the air being expanded and cooled in the expansion turbine to a pressure and temperature suitable for delivery to the aircraft cabin.

<CIT> discloses an auxiliary refrigerated air system includes first and second tandemly-arranged auxiliary turbine components, air dividing and mixing valves, an air bypass loop, an auxiliary air compressor, and a heat exchanger. The heat exchanger uses the turbine engine fuel to cool compressed air routed from the auxiliary compressor to the entrance side of the first auxiliary turbine component.

<CIT> discloses a compressing device including a turbine with a first inlet and a second inlet. The turbine provides energy by expanding mediums. First and second inlets are configured to receive first and second mediums respectively. The compressing device includes a compressor that receives a first energy derived from the first and second mediums being expanded across the turbine during a first mode of the compressing device, receives a second energy derived from the first medium being expanded across the turbine during a second mode of the compressing device, and compresses the second medium in accordance with the first mode or the second mode. The compressing device includes a motor that provides a supplementary energy to the compressor.

According to an aspect, a pressurization system for a vehicle is disclosed according to claim <NUM>.

In addition to one or more of the features described herein, in further embodiments the medium is ram air.

In addition to one or more of the features described herein, in further embodiments an expanded medium is provided at the turbine outlet and a compressed medium is provided at the compressor outlet, and within the heat exchanger, heat is configured to transfer from the compressed medium to the expanded medium.

In addition to one or more of the features described herein, in further embodiments the compressed medium at an outlet of the heat exchanger is provided to at least one component configured to further condition the compressed medium.

In addition to one or more of the features described herein, in further embodiments the at least one component configured to further condition the compressed medium further comprises a load heat exchanger.

In addition to one or more of the features described herein, in further embodiments the expanded medium provided at an outlet of the heat exchanger is exhausted overboard.

In addition to one or more of the features described herein, in further embodiments the vehicle is an aircraft.

According to an aspect, a method of conditioning a load of a vehicle is disclosed according to claim <NUM>.

In addition to one or more of the features described herein, in further embodiments the expanded medium output from the turbine is provided to the cooling heat exchanger as the cooling medium.

In addition to one or more of the features described herein, in further embodiments in a first mode, the compressor is driven in response to expanding the second portion of the medium within the turbine, and in a second mode, the compressor is driven by an electric motor and in response to expanding the second portion of the medium within the turbine.

In addition to one or more of the features described herein, in further embodiments exhausting the cooling medium from the cooling heat exchanger overboard.

In addition to one or more of the features described herein, in further embodiments providing the cooling medium from the cooling heat exchanger to another cooling heat exchanger.

In addition to one or more of the features described herein, in further embodiments delivering the compressed medium provided at an outlet of the cooling heat exchanger to at least one component configured to further condition the compressed medium.

In addition to one or more of the features described herein, in further embodiments further cooling the expanded medium within a load heat exchanger via another cooling medium.

With reference now to <FIG>, a schematic diagram of a portion of a pressurization system <NUM> is illustrated. The pressurization system <NUM> may be a refrigeration or air cycle subsystem and is configured to receive a medium A at an inlet <NUM>. In the illustrated, non-limiting embodiment, the medium is fresh air, such as outside air for example. This outside air, also referred to herein as RAM air, can be procured via one or more scooping mechanisms, such as an impact scoop or a flush scoop for example. When the pressurization system <NUM> is implemented on an aircraft, the medium A is generally at an ambient pressure equal to an air pressure outside of the aircraft when the aircraft is on the ground and is between an ambient pressure and a cabin pressure when the aircraft is in flight. It should be understood that any suitable medium A is within the scope of the disclosure. For example, other suitable mediums available on an aircraft include, but are not limited to bleed air, which is pressurized air originating from, i.e., being "bled" from, an engine or auxiliary power unit of the aircraft, or cabin discharge air, which is air leaving the cabin and that would typically be discharged overboard.

It should be understood that the elements of the pressurization system <NUM> are connected via valves, tubes, pipes, and the like. Valves (e.g., flow regulation device or mass flow valve) are devices that regulate, direct, and/or control a flow of a medium by opening, closing, or partially obstructing various passageways within the tubes, pipes, etc. of the system. Valves can be operated by actuators, such that flow rates of the medium in any portion of the pressurization system <NUM> can be regulated to a desired value.

The pressurization system <NUM> includes at least one cabin air compressing device <NUM>. The cabin air compressing device <NUM> is a mechanical device that includes one or more components for performing thermodynamic work on a medium (e.g., extracts work from the medium by raising and/or lowering the pressure thereof and by raising and/or lowering the temperature thereof.

The cabin air compressing device <NUM> includes a compressor <NUM> and a turbine <NUM> operably coupled by a shaft <NUM>. Accordingly, the cabin air compressing device <NUM> may also be referred to herein as a turboCAC. A compressor <NUM> is a mechanical device configured to raise a pressure of a medium and can be driven by another mechanical device (e.g., a motor or a medium via a turbine). Examples of compressor types include centrifugal, diagonal or mixed-flow, axial-flow, reciprocating, ionic liquid piston, rotary screw, rotary vane, scroll, diaphragm, air bubble, etc. A turbine <NUM> is a mechanical device that expands a medium and extracts work therefrom (also referred to as extracting energy) to drive the compressor <NUM> via the shaft <NUM>. Although only a two-wheel cabin air compressing device <NUM> is illustrated and described herein, it should be understood that embodiments having additional wheels, such as an additional compressor, turbine, and/or fan for example, are also within the scope of the disclosure.

An inlet <NUM> of the compressor <NUM> and an inlet <NUM> of the turbine <NUM> are both fluidly connected to the inlet <NUM>. Accordingly, a first portion of the flow of medium A from the inlet <NUM> may be provided to the compressor inlet <NUM> and a second portion of the flow of medium A from the inlet <NUM> may be provided to the turbine inlet <NUM> in parallel.

In an embodiment, the cabin air compressing device <NUM> additionally includes an electric motor <NUM> connected to the shaft <NUM> and operable to drive the compressor <NUM>. The motor <NUM> can receive power from a power source (not shown) such as generator or a power bus (e.g., a power bus of an aircraft). In embodiments including both a turbine <NUM> and a motor <NUM> connected to the shaft <NUM>, either or all of the turbine <NUM> and the motor <NUM> may be used to drive the compressor <NUM>.

The pressurization system <NUM> includes at least one cooling heat exchanger <NUM> arranged downstream from at least one of the compressor <NUM> and the turbine <NUM> relative to a flow of medium through the pressurization system <NUM>. The cooling heat exchanger <NUM> is configured to receive and cool a flow of compressed medium output from the compressor <NUM>. As shown, an outlet <NUM> of the compressor <NUM> is connected to a first or heated flow inlet <NUM> of the heat exchanger via a conduit <NUM>. The compressed medium A1 is cooled within the heat exchanger <NUM> by a cooling medium provided at a second or cooling flow inlet <NUM>. The cooling medium is the expanded medium A2 provided at the outlet <NUM> of the turbine <NUM>, the outlet <NUM> being connected to the cooling flow inlet <NUM> via a conduit <NUM>. Although the heat exchanger <NUM> is illustrated in <FIG> as a cross-flow heat exchanger, a skilled artisan will realize that the heat exchanger <NUM> can be any suitable type of heat exchanger that achieves the desired result of cooling the compressed medium A1.

The cooling heat exchanger <NUM> additionally includes a first or heated flow outlet <NUM> and a second or cooling flow outlet <NUM>. In an embodiment, the first heated flow outlet <NUM> of the heat exchanger <NUM> is fluidly coupled to a volume of the vehicle, such as a cabin for example. The first heated flow outlet <NUM> may be directly connected to a volume, such as via a conduit, or alternatively, the flow at the first heated flow outlet <NUM> may be provided to at least one component, such as of an environmental control system (ECS), operable to condition the compressed medium A1 for example, before it is delivered to the volume. The heated expanded medium A2 provided at the second cooling flow outlet <NUM> is exhausted overboard to the ambient atmosphere surrounding the vehicle. In an embodiment, the expanded medium A2 may be exhausted overboard directly from the second cooling flow outlet <NUM>, or may be provided to one or more other components before ultimately being exhausted overboard.

During operation of the pressurization system <NUM> in a first mode when the vehicle is at a high altitude, such as during a supersonic cruise condition for example, a first portion of the medium A provided at the inlet <NUM> is provided generally directly to the inlet <NUM> of the compressor <NUM>. The act of compressing the medium A, heats the medium A and increases the pressure of the medium A. At the same time, a second portion of the flow of medium A from the inlet <NUM> is provided to the inlet <NUM> of the turbine <NUM>. Within the turbine <NUM>, the medium A is expanded and work is extracted therefrom. The work extracted from the medium A within the turbine <NUM> is used to drive the compressor <NUM>. However, it should be understood that embodiments where the aircraft is not flying in a supersonic condition, the motor <NUM> may be used in combination with the energy extracted at the turbine to drive the compressor <NUM>. The expanded medium A2 output from the turbine <NUM> has a reduced temperature and pressure relative to the medium A provided to the inlet <NUM> of the turbine <NUM>.

The compressed medium A1 output from the outlet <NUM> of the compressor <NUM>, represented as A1, may then flow to the heated flow inlet <NUM> of the cooling heat exchanger <NUM>. Similarly, the expanded medium output from the turbine <NUM>, represented as A2, may then flow to the cooling flow inlet <NUM> of the cooling heat exchanger <NUM>. Within the cooling heat exchanger <NUM>, heat from the compressed medium A1 is transferred to the cooling medium A2, before the cooling medium A2 is exhausted overboard, such as via the second cooling flow outlet <NUM> for example, into the ambient atmosphere adjacent to the vehicle. As previously described, the compressed medium A1 provided at the heated flow outlet <NUM> of the cooling heat exchanger <NUM> is then provided to the volume or to one or more other components arranged upstream from the volume and configured to further condition the compressed medium A1.

A second mode of operation of the pressurization system <NUM> is substantially similar to the first mode of operation. However, in the second mode, a valve V1 arranged within a bypass conduit <NUM> is opened such that at least some, and in some embodiments all of the second portion of the flow A bypasses the turbine <NUM> via the bypass conduit <NUM>. In such embodiments, the cooling medium provided to the second cooling flow inlet <NUM> of the cooling heat exchanger <NUM> is either the medium A or a combination of the expanded medium A2 and the medium A.

With reference now to <FIG>, a pressurization system <NUM> is shown. The pressurization system <NUM> includes a first cabin air compressing device 24a and a second cabin air compressing device 24b, each of which includes a compressor 26a, 26b, turbine 28a, 28b, and motor 36a, 36b operably coupled to a shaft 30a, 30b as previously described. The first compressor 26a and the first turbine 28a are arranged in parallel relative to the inlet <NUM> as previously described. In addition, the second cabin air compressing device 24b is arranged in parallel with a portion of the first cabin air compressing device 24a. The second compressor 26b is arranged in parallel with the first compressor 26a and the first turbine 28a relative to a flow of medium A provided at the inlet <NUM>. Further, in a variant, the medium A provided at the inlet <NUM> is configured to flow through compressor 26b and the turbine 28b of the second cabin air compressing device 24b in series, as will be described in more detail below.

In <FIG>, the at least one cooling heat exchanger includes both a first cooling heat exchanger <NUM> and another cooling heat exchanger or second cooling heat exchanger <NUM> (also referred to herein as an outflow or regeneration heat exchanger). In <FIG>, these cooling heat exchangers <NUM>, <NUM> are co-located; however, this is not required. In one variant, the cooling heat exchangers <NUM>, <NUM> are contained in a single unit. For simplicity, in <FIG>, the connection that provides the transfer of the cooling medium from the first cooling heat exchanger <NUM> to the second heat exchanger <NUM> is not shown. As such, the unit comprising the first cooling heat exchanger <NUM> and the second cooling heat exchanger <NUM> includes a cooling medium inlet <NUM> at the first cooling heat exchanger <NUM> and cooling medium outlet <NUM> that is part of second cooling heat exchanger <NUM>. Although not shown, the first cooling heat exchanger <NUM> may include a cooling medium outlet (not shown) that provides the flow of cooling medium directly (or indirectly) to a cooling flow inlet (not shown) of the second cooling heat exchanger <NUM>. It shall be understood that the input/output need not be a physical object and can be formed such that the path from the heated flow inlet <NUM> to the outlet <NUM> is a continuous path.

The pressurization system <NUM> additionally includes at least one heat exchanger arranged downstream from one or more components of the second cabin air compression device 24b. In <FIG> and <FIG>, the at least one heat exchanger includes a first heat exchanger <NUM>, also referred to herein as a load heat exchanger, and a second heat exchanger <NUM>. These heat exchangers <NUM>, <NUM> may, but need not be contained in a single unit. The first heat exchanger <NUM> includes a first inlet <NUM> and a first outlet <NUM> arranged along a flow path and the second heat exchanger <NUM> similarly includes a first inlet <NUM> and a first outlet <NUM> arranged along a flow path. As shown, the first inlet <NUM> of the first heat exchanger <NUM> may be fluidly connected, directly or indirectly, to the heated flow outlet <NUM> of the first cooling heat exchanger <NUM>. Alternatively, or in addition, the first inlet <NUM> of the second heat exchanger <NUM> may be fluidly connected directly, or indirectly, to a first or heated flow outlet <NUM> of the second cooling heat exchanger <NUM>.

The unit comprising the first heat exchanger <NUM> and the second heat exchanger <NUM> includes a second or cooling medium inlet <NUM> at the first heat exchanger <NUM> and second or cooling medium outlet <NUM> that is part of second heat exchanger <NUM>. Although not shown, the first heat exchanger <NUM> may include a cooling medium outlet (not shown) that provides the flow of cooling medium directly (or indirectly) to a cooling flow inlet (not shown) of the second heat exchanger <NUM> to define a secondary cooling flow path through the heat exchangers <NUM>, <NUM>. It shall be understood that the input/output need not be a physical object and can be formed such that the path from the second cooling medium inlet <NUM> to the second cooling medium outlet <NUM> is a continuous path.

Another cooling medium, also referred to herein as a second cooling medium, is provided to the cooling flow path extending through between the second cooling medium inlet <NUM> to the second cooling medium outlet <NUM> of the heat exchangers <NUM>, <NUM>. In <FIG>, the compressed medium output from the compressors 24a and 24b are cooled within the first heat exchanger <NUM> and the second heat exchanger <NUM>, respectively, is cooled by a second cooling medium A2b provided at second cooling medium inlet <NUM>. The second cooling medium is expanded medium output from the outlet of the turbine 28b of the second cabin air compression device 24b. Although the first and second cooling mediums are illustrated and described herein as being exhausted overboard to the ambient atmosphere surrounding the vehicle, it should be understood that in other embodiments, the cooling mediums may be provided to another load of the vehicle.

In a variant, the pressurization system <NUM> additionally includes a turbofan <NUM> including a turbine <NUM> operably coupled to a fan <NUM> by a shaft <NUM>. As shown, the turbine <NUM> may be arranged downstream from and is in fluid communication with the first outlet <NUM> of the load heat exchanger <NUM> relative to a flow of compressed medium. The flow provided at the outlet of the turbine <NUM> may be further conditioned within a heat exchanger before being delivered to a load, such as the cabin for example.

During operation of the pressurization system <NUM> of <FIG>, the medium A provided at the inlet <NUM> is provided generally directly and simultaneously to each of an inlet of the compressor 26a, the turbine 28a, and the compressor 26b. The medium A is compressed within the compressor 26a, and as a result, the compressed medium A1a output from the compressor 26a has an increased pressure and temperature relative to the medium A at the inlet <NUM>. Within the turbine 28a, the medium A is expanded and work is extracted therefrom. The work extracted from the medium A within the turbine 28a in combination with the energy provided by the motor 36a is used to drive the compressor 26a. The expanded medium A2a output from the turbine 28a has a reduced temperature and pressure relative to the medium A provided to the inlet of the turbine 28a. Similarly, the compressed medium A1b output from the compressor 26b has an increased pressure and temperature relative to the medium A at the inlet <NUM>.

The flow of first compressed medium A1a output from the compressor 26a is provided to the heated flow inlet <NUM> of the first cooling heat exchanger <NUM>, and the flow of the second compressed medium A1b output from the compressor 26b is provided to the heated flow inlet <NUM> of the second cooling heat exchanger <NUM>. Within each of the first cooling heat exchanger <NUM> and the second cooling heat exchanger <NUM>, the respective compressed mediums A1a, A1b are cooled by the first cooling medium. In <FIG>, the first cooling medium is the expanded medium A2a output from the turbine 28a of the first cabin air compression device 24a. The first cooling medium A2a provided at the cooling flow outlet <NUM> of the second cooling heat exchanger <NUM> may be drawn through the fan <NUM> of the turbofan <NUM> and exhausted overboard. However, in other variants, the first cooling medium A2a provided at the cooling flow outlet <NUM> may be configured to bypass the fan <NUM> and is exhausted overboard.

The compressed medium A1a output from the first cooling heat exchanger <NUM> is configured to pass through a flow path extending between the first inlet <NUM> and the first outlet <NUM> of the first heat exchanger <NUM>. At the same time, the compressed medium A1b output from the second cooling heat exchanger is configured to pass through a flow path extending between the first inlet <NUM> and the first outlet <NUM> of the second heat exchanger <NUM>. Within the second heat exchanger <NUM>, the compressed medium A1b is cooled by a second cooling medium, to be described in more detail below. From the first outlet <NUM> of the second heat exchanger <NUM>, the further cooled compressed medium A1b is provided to the inlet of the turbine 28b of the second cabin air compression device 24b.

Within the turbine 28b, the compressed medium A1b is expanded and work is extracted therefrom. The work extracted from the medium A1b within the turbine 28b in combination with the energy provided by the motor 36b is used to drive the compressor 26b. The expanded medium A2b output from the turbine 28b has a reduced temperature and pressure relative to the second compressed medium A1b provided to the inlet of the turbine 28b.

The expanded medium A2b output from the turbine 28b is provided to the continuous fluid flow path extending between the second cooling medium inlet <NUM> of the first heat exchanger <NUM> and the second cooling medium outlet <NUM> of the second heat exchanger <NUM>. Accordingly, in a variant, the expanded medium A2b is heated via the heat exchange relationship with the compressed medium A1a in the first heat exchanger <NUM> and the heat exchange relationship with the compressed medium A1b in the second heat exchanger <NUM>. The resulting heated cooling medium A2b provided at the second outlet <NUM> may be exhausted overboard.

In a variant, the cooled compressed medium A1a provided at the first outlet <NUM> of the first heat exchanger <NUM> passes through a water collector <NUM> before being provided to the inlet of the turbine <NUM> of the turbofan <NUM>. Within the turbine <NUM>, the compressed medium A1a is expanded and work is extracted therefrom. The work extracted from the medium A1a is used to drive the fan <NUM> via the shaft <NUM>. From the outlet of the turbine <NUM>, the expanded medium A3 is provided to the cabin <NUM> or to one or more other loads. It should be understood that the configuration of the pressurization system <NUM> illustrated and described in <FIG> is intended as an example only and that any suitable configuration operable to condition one or more flows of medium therein is within the scope of the disclosure.

Claim 1:
A pressurization system (<NUM>) for a vehicle comprising:
an inlet (<NUM>) for receiving a medium (A);
a cabin air compressing device (<NUM>) arranged in fluid communication with the inlet (<NUM>), the cabin air compressing device (<NUM>) comprising:
a shaft (<NUM>);
a compressor (<NUM>) connected to the shaft (<NUM>), the compressor (<NUM>) having a compressor inlet (<NUM>) and a compressor outlet (<NUM>);
a motor (<NUM>) operably connected to the shaft (<NUM>) and configured to drive the compressor (<NUM>); and
a turbine (<NUM>) connected to the shaft (<NUM>) and also configured to drive the compressor (<NUM>) upon receipt of the medium (A), the turbine (<NUM>) having a turbine inlet (<NUM>) and a turbine outlet (<NUM>); and
a heat exchanger (<NUM>) having a first inlet (<NUM>) fluidly connected to the compressor outlet (<NUM>) and having a second inlet (<NUM>) fluidly connected to the turbine outlet (<NUM>);wherein the compressor inlet (<NUM>) and the turbine inlet (<NUM>) are fluidly connected to and are fluidly arranged in parallel relative to the inlet (<NUM>) such that a first portion of the flow of the medium (A) from the inlet (<NUM>) is provided to the compressor inlet (<NUM>) and a second portion of the flow of the medium (A) from the inlet (<NUM>) is provided to the turbine inlet (<NUM>) in parallel;
characterized by:
a bypass conduit (<NUM>) connecting the inlet (<NUM>) and the second inlet (<NUM>) of the heat exchanger (<NUM>); and
a valve (V1) associated with the bypass conduit (<NUM>).