Abstract: An environmental control system of an aircraft includes a primary heat exchanger, a secondary heat exchanger and an air cycle machine. The air cycle machine includes a compressor fluidly coupled to an outlet of the primary heat exchanger and an inlet of the secondary heat exchanger, a dehumidification system arranged in fluid communication with the outlet of the secondary heat exchanger, a first turbine fluidly coupled to an outlet of the secondary heat exchanger and optionally a second turbine disposed downstream of the first turbine that receives air from the first turbine in a normal mode a first humidity sensor disposed fluidly between the first turbine and the second turbine that measures humidity of air that has left the first turbine as it enters the second turbine in the normal mode.

Abstract: An environmental control system of an aircraft includes a ram air circuit including a ram air shell having a plurality of heat exchangers positioned therein, the plurality of heat exchangers including a first heat exchanger, a second heat exchanger, and a third heat exchanger. The ram air circuit is configured and arranged so that a first medium received at the first heat exchanger passes through the first heat exchanger and then through the third heat exchanger and so that a second medium received at the second heat exchanger passes through the second heat exchanger. A compressing device is arranged in fluid communication with the ram air circuit.

Abstract: A system includes a venturi duct, a first delta P sensor, a second delta P sensor, and an ECS controller. The venturi duct is configured to receive a first bleed air flow or a second bleed air flow. The first and second delta P sensors are configured to sense a first and second pressure difference between a first point and a second point of the venturi duct. The first and second delta P sensors are configured to sense pressure difference over different pressure ranges. The ECS controller is configured determine a flow rate of an ECS air flow based upon the first pressure and/or second sensed pressure differences.

Abstract: A bleed valve control system for mounting to a support structure adjacent to a fan air plenum within an aircraft includes a bleed valve module, a pneumatic valve controller, and a fan air duct. The bleed valve module includes a pipe, a plurality of bleed valves connected to the pipe, and a plurality of pneumatic actuators connected to the bleed valves. The pneumatic valve controller includes a plurality of electrical control elements and a cooling shroud. The cooling shroud is attached to the pipe and at least partially surrounds the plurality of electrical control elements. The fan air duct connects the cooling shroud to the fan air plenum such that fan air flows through the cooling shroud to cool the plurality of electrical control elements.

Abstract: A system and method that comprises an air cycle machine, a flow of bleed air, at least one heat exchanger, and an inlet configured to supply the flow of the bleed air is provided. The bleed air flows from a source to mix with recirculated air in accordance with a high pressure mode or a recirculation chilling mode. The system and method also can also utilize the recirculated air flowing from the chamber to drive or maintain the air cycle machine in accordance with the above modes.

Abstract: Provided are embodiments including a system and method for operating a reconfigurable control architecture for programmable logic devices. Some embodiments include a storage medium that is coupled to a programmable logic device and a dispatch mechanism that is operably coupled to the programmable logic device. In embodiments, the dispatch mechanism is configured is receive an object, select one or more constructs of the programmable logic device based on the object, schedule one or more inputs and outputs for each of the selected constructs based on the object, and execute a system level operation indicated by the object based on the schedule.

Abstract: An aircraft environmental control system (ECS) includes a first valve that is adjustable between a plurality of first positions to open or shut-off a bleed air flow that flows from an inlet of the first valve to an outlet of the first valve. A second valve includes an inlet in fluid communication with the first valve outlet, and is adjustable between a plurality of second positions to throttle the bleed air that flows from the inlet of the second valve to an outlet of the second valve. A valve position sensor outputs a position signal indicating a measured position among the plurality of second positions. A controller is in signal communication with the valve position sensor. The controller is configured to determine a primary effective area of the second valve based on the measured position, and to diagnose operation of the first valve based on the primary effective area.

Abstract: Provided are embodiments including a system and method for operating a reconfigurable control architecture for programmable logic devices. Some embodiments include a storage medium that is coupled to a programmable logic device and a dispatch mechanism that is operably coupled to the programmable logic device. In embodiments, the dispatch mechanism is configured is receive an object, select one or more constructs of the programmable logic device based on the object, schedule one or more inputs and outputs for each of the selected constructs based on the object, and execute a system level operation indicated by the object based on the schedule.

Abstract: A system includes a venturi duct, a first delta P sensor, a second delta P sensor, and an ECS controller. The venturi duct is configured to receive a first bleed air flow or a second bleed air flow. The first and second delta P sensors are configured to sense a first and second pressure difference between a first point and a second point of the venturi duct. The first and second delta P sensors are configured to sense pressure difference over different pressure ranges. The ECS controller is configured determine a flow rate of an ECS air flow based upon the first pressure and/or second sensed pressure differences.

Abstract: A computer-implemented method for designing a built-in test is described. The method includes receiving, via a processor, a subsystem model including system parameters for a heat exchanger, wherein each of the system parameters includes a sensor variance; determining, via the processor, a test design vector based on one or more of the system parameters; and designing, via the processor, the built-in test based on the test design vector.

Abstract: An aircraft environmental control system (ECS) includes a first valve that is adjustable between a plurality of first positions to open or shut-off a bleed air flow that flows from an inlet of the first valve to an outlet of the first valve. A second valve includes an inlet in fluid communication with the first valve outlet, and is adjustable between a plurality of second positions to throttle the bleed air that flows from the inlet of the second valve to an outlet of the second valve. A valve position sensor outputs a position signal indicating a measured position among the plurality of second positions. A controller is in signal communication with the valve position sensor. The controller is configured to determine a primary effective area of the second valve based on the measured position, and to diagnose operation of the first valve based on the primary effective area.

Abstract: A bleed valve control system for mounting to a support structure adjacent to a fan air plenum within an aircraft includes a bleed valve module, a pneumatic valve controller, and a fan air duct. The bleed valve module includes a pipe, a plurality of bleed valves connected to the pipe, and a plurality of pneumatic actuators connected to the bleed valves. The pneumatic valve controller includes a plurality of electrical control elements and a cooling shroud. The cooling shroud is attached to the pipe and at least partially surrounds the plurality of electrical control elements. The fan air duct connects the cooling shroud to the fan air plenum such that fan air flows through the cooling shroud to cool the plurality of electrical control elements.

Abstract: An environmental control system of an aircraft includes a ram air circuit including a ram air shell having a plurality of heat exchangers positioned therein, the plurality of heat exchangers including a first heat exchanger, a second heat exchanger, and a third heat exchanger. The ram air circuit is configured and arranged so that a first medium received at the first heat exchanger passes through the first heat exchanger and then through the third heat exchanger and so that a second medium received at the second heat exchanger passes through the second heat exchanger. A compressing device is arranged in fluid communication with the ram air circuit.

Abstract: A bleed valve control system for mounting to a support structure adjacent to a fan air plenum within an aircraft includes a bleed valve module, a pneumatic valve controller, and a fan air duct. The bleed valve module includes a pipe, a plurality of bleed valves connected to the pipe, and a plurality of pneumatic actuators connected to the bleed valves. The pneumatic valve controller includes a plurality of electrical control elements and a cooling shroud. The cooling shroud is attached to the pipe and at least partially surrounds the plurality of electrical control elements. The fan air duct connects the cooling shroud to the fan air plenum such that fan air flows through the cooling shroud to cool the plurality of electrical control elements.

Abstract: An environmental control system includes an air cycle machine. The air cycle machine includes a compressor section with a compressor inlet and a compressor outlet, and a first turbine section with a first turbine inlet and a first turbine outlet. The environmental control system further includes a first turbine bypass shutoff valve positioned at the first turbine inlet. The first turbine bypass shutoff valve is configured to shut off the flow of air to the first turbine inlet.

Abstract: A distributed control system includes a local feedback controller, a sensor, and a controller. The local feedback controller is in communication with an actuator arranged to control a position of a valve associated with a conduit. The sensor is arranged to provide a signal indicative of at least one of a pressure, flow rate, and a temperature of a fluid within the conduit to the local feedback controller. The controller is programmed to provide a target control reference to the local feedback controller.

Abstract: A system and method that comprises an air cycle machine, a flow of bleed air, at least one heat exchanger, and an inlet configured to supply the flow of the bleed air is provided. The bleed air directly flows from a source to mix with recirculated air downstream of a compressor of the air cycle machine in accordance with a high pressure mode or a recirculation chilling mode. The system and method can also utilize the recirculated air flowing from the chamber to drive or maintain the air cycle machine in accordance with the above modes.

Abstract: A system and method that comprises an air cycle machine, a flow of bleed air, at least one heat exchanger, and an inlet configured to supply the flow of the bleed air is provided. The bleed air directly flows from a source to either a compressor of the air cycle machine or the at least one heat exchanger in accordance with a high pressure, low pressure, or pressure boost operation mode. The system and method also can also utilize recirculated air flowing from the chamber to drive or maintain the air cycle machine in accordance with the above modes.

Abstract: A bleed valve control system for mounting to a support structure adjacent to a fan air plenum within an aircraft includes a bleed valve module, a pneumatic valve controller, and a fan air duct. The bleed valve module includes a pipe, a plurality of bleed valves connected to the pipe, and a plurality of pneumatic actuators connected to the bleed valves. The pneumatic valve controller includes a plurality of electrical control elements and a cooling shroud. The cooling shroud is attached to the pipe and at least partially surrounds the plurality of electrical control elements. The fan air duct connects the cooling shroud to the fan air plenum such that fan air flows through the cooling shroud to cool the plurality of electrical control elements.

Abstract: A matched venturi assembly is provided and includes a venturi component configured to provide for fluid communication between an inlet and an outlet, sensors coupled to the venturi component and configured to generate readings of characteristics of fluid flows proceeding through the venturi component and a venturi controller, which is receptive of the readings from the sensors. The venturi controller is configured to interpret the readings and is trimmable in a test phase where fluid flows with known characteristics are flown through the venturi component and interpretations of the readings are calibrated in accordance with differences between the readings and the known characteristics.