A fluid flow system includes a main valve having a spool, a first chamber, and a second chamber. A pressure difference between the first chamber and the second chamber is configured to move the spool to control fluid flow. An electromechanical meter interface device (EMID) is in fluid communication with at least one of the first and second chambers of the main valve. The EMID is configured to meter fluid from a first source and a second source to the at least one of the first chamber and the second chamber. The first source has a different pressure from the second source. A fixed orifice is arranged between the main valve and the EMID. A fuel system for a gas turbine engine is also disclosed.

The present disclosure relates to systems and methods that are useful in control of one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants, methods of starting power production plants, and methods of generating power with a power production plant wherein one or more control paths are utilized for automated control of at least one action. The present disclosure more particularly relates to power production plants, control systems for power production plants, and methods for startup of a power production plant.

The present disclosure relates to systems and methods that are useful in control of one or more aspects of a power production plant. More particularly, the disclosure relates to power production plants, methods of starting power production plants, and methods of generating power with a power production plant wherein one or more control paths are utilized for automated control of at least one action. The present disclosure more particularly relates to power production plants, control systems for power production plants, and methods for startup of a power production plant.

Methods and systems of starting a gas turbine engine are provided. During startup, a fuel pressure associated with a primary fuel supply of the gas turbine engine is monitored. A low-pressure event for the primary fuel supply is detected when the fuel pressure falls below a predetermined threshold. Responsive to detecting the low pressure event, an electric backup boost pump is activated by an engine controller to provide fuel to the gas turbine engine.

Methods and systems of starting a gas turbine engine are provided. During startup, a fuel pressure associated with a primary fuel supply of the gas turbine engine is monitored. A low-pressure event for the primary fuel supply is detected when the fuel pressure falls below a predetermined threshold. Responsive to detecting the low pressure event, an electric backup boost pump is activated by an engine controller to provide fuel to the gas turbine engine.

A turbine device includes a fluid compressing device compressing a fluid, a combustion device, a fuel supply device supplying a fuel to the combustion device, the combustion device combusting a mixture of the fluid and the fuel, a sensing device, and a control device. The sensing device senses a humidity of the fluid compressed in the fluid compressing device. The control device controls the supply of the fuel by the fuel supply device based on the humidity sensed by the sensing device.

A turbine device includes a fluid compressing device compressing a fluid, a combustion device, a fuel supply device supplying a fuel to the combustion device, the combustion device combusting a mixture of the fluid and the fuel, a sensing device, and a control device. The sensing device senses a humidity of the fluid compressed in the fluid compressing device. The control device controls the supply of the fuel by the fuel supply device based on the humidity sensed by the sensing device.

A filter assembly includes a manifold having a fluid inlet and a fluid outlet, a filter housing having a filter medium provided therein, the filter medium defining an inner filter chamber and defining an outer filter chamber between the filter medium and the filter housing, the filter housing being removably attached to the manifold. The filter assembly includes a valve assembly mounted inside the manifold, and a by-pass channel defined inside the manifold between the fluid inlet and the fluid outlet. The valve assembly includes a valve body, a by-pass valve system, and a shut off valve system. The by-pass valve system includes a by-pass valve piston having a piston body, and a by-pass valve spring arranged to move the by-pass valve piston. The shut off valve system includes a shut off valve piston, and a shut off valve spring arranged to move the shut off valve piston.

A filter assembly includes a manifold having a fluid inlet and a fluid outlet, a filter housing having a filter medium provided therein, the filter medium defining an inner filter chamber and defining an outer filter chamber between the filter medium and the filter housing, the filter housing being removably attached to the manifold. The filter assembly includes a valve assembly mounted inside the manifold, and a by-pass channel defined inside the manifold between the fluid inlet and the fluid outlet. The valve assembly includes a valve body, a by-pass valve system, and a shut off valve system. The by-pass valve system includes a by-pass valve piston having a piston body, and a by-pass valve spring arranged to move the by-pass valve piston. The shut off valve system includes a shut off valve piston, and a shut off valve spring arranged to move the shut off valve piston.

Methods and systems for starting an aircraft gas turbine engine are described. The method comprises, in a first phase of a startup upon receipt of a start request, modifying a first set of engine control parameters to cause light-up; in a second phase of the startup, modifying a second set of engine control parameters to set conditions for light-around; and in a third phase of the startup, modifying a third set of engine control parameters to propagate a flame around a combustor of the gas turbine engine.