Abstract

The invention relates to an aircraft having a fuel cell (20) and an air supply device (30) for feeding air for operating the fuel cell (20) and for cooling a heat exchanger (21) connected to the fuel cell (20), wherein the aircraft (1) has at least one air channel (10), the cross-section of which expands in the direction of flow (5) of the air downstream of an air inlet opening (11) in at least one region (35) of the peripheral surface. The invention also relates to a method for operating such a fuel cell (20) of an aircraft (1) with an air supply device (30) for operating the fuel cell (20) and for cooling a heat exchanger (21) connected to the fuel cell (20).

IPC Classes  ?

• B64D 37/34 - Conditioning fuel, e.g. heating
• F02C 7/10 - Heating air supply before combustion, e.g. by exhaust gases by means of regenerative heat-exchangers

Abstract

A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a turbine section including a fan drive turbine, a compressor section driven by the turbine section, a geared architecture driven by the fan drive turbine, and a fan driven by the fan drive turbine via the geared architecture. At least one stage of the turbine section includes an array of rotatable blades and an array of vanes. A ratio of the number of vanes to the number blades is greater than or equal to about 1.55. A mechanical tip rotational Mach number of the blades is configured to be greater than or equal to about 0.5 at an approach speed.

IPC Classes  ?

• F02C 7/24 - Heat or noise insulation
• F01D 1/02 - Non-positive-displacement machines or engines, e.g. steam turbines with stationary working-fluid guiding means and bladed or like rotor
• F02K 3/06 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low-pressure outputs, for augmenting jet thrust, e.g. of double-flow type with front fan

Abstract

A gas turbine engine is utilized in combination with a gear reduction to reduce the speed of a fan relative to a low pressure turbine speed. The gas turbine engine is designed such that a blade count in the low pressure turbine multiplied by the speed of the low pressure turbine will result in operational noise that is above a sensitive range for human hearing. A method and turbine module are also disclosed.

IPC Classes  ?

• F02C 3/107 - Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor with two or more rotors connected by power transmission
• F01D 5/02 - Blade-carrying members, e.g. rotors
• F02K 3/06 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low-pressure outputs, for augmenting jet thrust, e.g. of double-flow type with front fan

Abstract

A gear reduction effects a reduction in the speed of a fan relative to a speed of a low pressure turbine and a low pressure compressor portion. At least one of the low pressure turbine portion and low pressure compressor portion has a number of blades in each of a plurality of rows. The blades operate at least some of the time at a rotational speed. The number of blades and the rotational speed are such that the following formula holds true for at least one of the blade rows of the at least one of the low pressure turbine portion and/or the low pressure compressor sections: (number of blades x rotational speed)/60 ? 5500 Hz. The rotational speed is an approach speed in revolutions per minute.

IPC Classes  ?

• F02K 3/06 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber the plant including ducted fans, i.e. fans with high volume, low-pressure outputs, for augmenting jet thrust, e.g. of double-flow type with front fan
• F01D 5/02 - Blade-carrying members, e.g. rotors
• F02C 3/107 - Gas-turbine plants characterised by the use of combustion products as the working fluid having a turbine driving a compressor with two or more rotors connected by power transmission
• F02K 3/02 - Plants including a gas turbine driving a compressor or a ducted fan in which part of the working fluid by-passes the turbine and combustion chamber