In one embodiment, an apparatus includes a first seal and a perforated cover. The first seal may comprise one or more inlet apertures and be located proximate to an opening into an interior of a nacelle. The perforated cover may be slidably engaged with the first seal and configured to vary an amount of air allowed into the interior of the nacelle.

The present disclosure relates to the field of air conditioning technology. In particular, it involves an air control method for air handler unit.

A control system and method utilizing one or more processors that are configured to determine contaminant loading of blades of a turbomachinery compressor based on one or more environmental conditions to which the turbomachinery compressor is exposed and one or more atmospheric air inlet conditions of the turbomachinery compressor. The one or more processors then determine a corrosion contaminant concentration on the blades of the turbomachinery compressor based on the contaminant loading that is determined and determine an upper limit on or a distribution of potential corrosion of the blades of the turbomachinery based on the corrosion contaminant concentration, at least one of the environmental conditions to which the turbomachinery compressor is exposed, and the corrosion contaminant concentration that is determined.

In one embodiment, an apparatus includes a first seal and a perforated cover. The first seal may comprise one or more inlet apertures and be located proximate to an opening into an interior of a nacelle. The perforated cover may be slidably engaged with the first seal and configured to vary an amount of air allowed into the interior of the nacelle.

The disclosure includes controlling a pressure ratio for a compressing system, comprising introducing a quantity of liquid into an input stream to create a multiphase input stream, compressing the multiphase input stream with a centrifugal compressor to create a discharge stream, measuring a parameter of the discharge stream, wherein the discharge parameter corresponds to a pressure ratio for the centrifugal compressor, when the parameter exceeds a first predetermined point, increasing a pressure ratio of the centrifugal compressor by increasing the quantity of liquid introduced, and when the parameter exceeds a second predetermined point, decreasing the pressure ratio by decreasing the quantity of liquid introduced.

An auxiliary power unit (APU) control system for an aircraft is disclosed. The APU control system includes an APU, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive a one or more ambient signals indicative of an air density value and one or more power signals indicative of a specific amount of power generated by the APU. The APU control system is further caused to determine a variable rotational speed of the APU based on the air density value and instruct the APU to operate at the variable rotational speed. The APU continues to generate the specific amount of power when operating at the variable rotational speed.

An auxiliary power unit (APU) control system for an aircraft is disclosed, and includes an APU drivingly coupled to one or more generators, one or more processors, and a memory coupled to the one or more processors. The memory stores data comprising a database and program code that, when executed by the one or more processors, causes the APU control system to receive one or more ambient signals indicative of an air density value and one or more power signals indicative of a specific amount of power generated by the APU. The system is further caused to determine a first variable rotational speed of the APU based on the air density value. The APU continues to generate the specific amount of power when operating at the first variable rotational speed. After instructing the APU to operate at the first variable rotational speed, the system receives an electrical load signal.

A measuring device, in particular for a flow inside a turbomachine, in particular in an aircraft engine. The measuring device includes at least one suction intake opening for fluid from an area of a mixed-out flow, wherein the at least one suction intake opening is arranged at a distance from a wall that delimits the flow, and fluid that is suctioned in through a fluid channel can be conducted to a sensor device.

A method of reducing applied heat within an inlet duct of a gas turbine generating electricity includes applying heat to the inlet duct of the gas turbine to attain an initial temperature set point and to produce conditions sufficient for preventing formation of ice within the inlet duct, measuring a position of an inlet guide vane (IGV) of the gas turbine, an inlet duct temperature, and an inlet duct relative humidity to determine a thermodynamic state in the inlet duct, evaluating the thermodynamic state to determine if the conditions are sufficient for preventing formation of ice within the inlet duct, and in response to determining that sufficient conditions exist within the inlet duct for preventing formation of ice, adjusting the applied heat to maintain the measured inlet duct temperature.

A method of reducing applied heat within an inlet duct of a gas turbine generating electricity includes applying heat to the inlet duct of the gas turbine to attain an initial temperature set point and to produce conditions sufficient for preventing formation of ice within the inlet duct, measuring a position of an inlet guide vane (IGV) of the gas turbine, an inlet duct temperature, and an inlet duct relative humidity to determine a thermodynamic state in the inlet duct, evaluating the thermodynamic state to determine if the conditions are sufficient for preventing formation of ice within the inlet duct, and in response to determining that sufficient conditions exist within the inlet duct for preventing formation of ice, adjusting the applied heat to maintain the measured inlet duct temperature.