Patent Application
20200158063
The present disclosure relates to fluid and lubrication systems, and more specifically to the attenuation of pressure pulses caused by pumps in fluid and lubrication systems.
Many aircraft engine fuel and lubrication systems include gear pumps to circulate fuel and oil. A gear pump can create pressure pulses that travel upstream of a pump inlet, with the amplitude and frequency of the pulses related to the number of gear teeth and rotation speed of the gear pump. In some cases these pressure pulses can be of the same order or even greater than the fluid inlet pressure. When the pressure pulses match or exceed the fluid inlet pressure, these pressure pulses can cause cavitation, wear, and fatigue in housings and lines in the system. Pressure pulses can also adversely impact pressure sensor readings.
In one aspect of the disclosure, a fluid pulsation attenuating arrangement includes an enclosure and a tubular member. The tubular member extends through the enclosure defining a chamber outside of the tubular member but inside of the enclosure. The tubular member includes a wall separating an interior passage of the tubular member and the chamber. A plurality of holes is formed in the wall and fluidically connects the chamber to the interior passage. An energy absorber is inside the chamber.
In another aspect of the disclosure, a fluid pulsation attenuator includes a pressure vessel enclosing a chamber and a fluid line extending through the pressure vessel. A plurality of holes is formed in the fluid line inside the pressure vessel. The plurality of holes fluidically connects the chamber and an interior passage of the fluid line. The fluid pulsation attenuator further includes a plurality of fibers inside the chamber. The plurality of fibers fills the chamber and surrounds the fluid line.
In another aspect of the disclosure, a fluid system includes a pump and a fluid pulsation attenuator fluidically connected to the pump. The fluid pulsation attenuator comprises a pressure vessel enclosing a chamber and a fluid line extending through the pressure vessel. A plurality of openings is formed in the fluid line inside the pressure vessel. The plurality of openings fluidically connects the chamber and an interior passage of the fluid line. The fluid pulsation attenuator also includes a cushion inside the chamber.
Persons of ordinary skill in the art will recognize that other aspects and embodiments of the present invention are possible in view of the entirety of the present disclosure, including the accompanying figures.
While the above-identified drawing figures set forth one or more embodiments of the invention, other embodiments are also contemplated. In all cases, this disclosure presents the invention by way of representation and not limitation. It should be understood that numerous other modifications and embodiments can be devised by those skilled in the art, which fall within the scope and spirit of the principles of the invention. The figures may not be drawn to scale, and applications and embodiments of the present invention may include features and components not specifically shown in the drawings. Like reference numerals identify similar structural elements.
The present disclosure provides a fluid pulsation attenuator that attenuates fluid pulsations caused by pumps. The fluid pulsation attenuator includes a pressure vessel enclosing a chamber and a fluid line extending through the pressure vessel and the chamber. Holes are formed in the fluid line inside the pressure vessel and the chamber is filled with a cushion. During operation, fluid flows through the fluid line and any pulsations in the fluid line can expand radially into the holes and be absorbed by the cushion. By absorbing the pulsations in the fluid, the fluid pulse attenuator reduces fatigue to lines and housings in a fluid system that incorporates the fluid pulse attenuator. This reduction in fatigue allows the lines and housings in the fluid system to be made from lighter and thinner structures. Furthermore, the attenuation of the pulsations by the fluid pulsation attenuator allows for more accurate sensor readings of the fluid. The fluid pulsation attenuator is described and discussed below with reference to the figures.
Pressure vessel 12 is a case or container that encloses chamber 14. As shown in
The plurality of holes 30 are formed in a portion of fluid line 16 inside pressure vessel 12. The plurality of holes 30 fluidically connect chamber 14 and interior passage 28 of fluid line 16. As shown in
Gear pump 38 circulates fluid F through fluid system 36 incrementally as the gears in gear pump 38 rotate. Because gear pump 38 circulates fluid F incrementally, gear pump 38 can cause pulsations P to occur in fluid F upstream of gear pump 38. As pulsations P travel upstream, pulsations P enter outlet 26 of fluid pulsation attenuator 10. As pulsations P enter pressure vessel 12, pulsations P are able to expand radially through the plurality of holes 30 in fluid line 16 and interact with cushion 18. The fibers of cushion 18 absorb and dissipate the energy of pulsations P, thereby reducing the amplitude of pulsations P as pulsations P travel upstream through fluid pulsation attenuator 10. When reaching inlet 24, the amplitude pulsations P is so reduced that pulsations P have completely dissipated, or dissipated to such a degree that pulsations P are unable to cause any damage or interference in fluid system 36.
In view of the foregoing description, it will be recognized that the present disclosure provides numerous advantages and benefits. For example, the present disclosure provides fluid pulsation attenuator 10 that attenuates pulsations P in fluid F caused by gear pump 38. Fluid pulsation attenuator 10 includes pressure vessel 12 encloses chamber 14 and fluid line 16 extends through pressure vessel 12 and chamber 14. Holes 30 are formed in fluid line 16 inside pressure vessel 12 and chamber 14 is filled by cushion 18. During operation, fluid F flows through fluid line 16 and any pulsations P in fluid line 16 can expand radially into holes 30 and be absorbed by cushion 18. By absorbing pulsations P in fluid F, fluid pulse attenuator 10 reduces fatigue to lines and housings in fluid system 36 that incorporates fluid pulse attenuator 10. This reduction in fatigue allows the lines and housings in fluid system 36 to be made from lighter and thinner structures. Furthermore, the attenuation of pulsations P in fluid F by fluid pulsation attenuator 10 allows for more accurate sensor readings of fluid F.
The following are non-exclusive descriptions of possible embodiments of the present invention.
In one embodiment, a fluid pulsation attenuating arrangement includes an enclosure and a tubular member. The tubular member extends through the enclosure defining a chamber outside of the tubular member but inside of the enclosure. The tubular member includes a wall separating an interior passage of the tubular member and the chamber. A plurality of holes is formed in the wall and fluidically connects the chamber to the interior passage. An energy absorber is inside the chamber.
The arrangement of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
the cushion comprises a pad of fibers that fills the chamber and surrounds the wall;
at least one hole of the plurality of holes extends radially through the wall;
the enclosure is cylindrical and the tubular member is coaxial with the enclosure;
the tubular member further comprises: an inlet extending axially outward from the enclosure; and an outlet extending axially outward from the enclosure in a direction that is opposite the inlet; and/or
the tubular member comprises: a first solid tube extending into the enclosure and forming the inlet of the tubular member; a second solid tube extending into the enclosure and forming the outlet of the tubular member; and a mesh tube inside the enclosure and connected between the first solid tube and the second solid tube.
In another embodiment, a fluid pulsation attenuator includes a pressure vessel enclosing a chamber and a fluid line extending through the pressure vessel. A plurality of holes is formed in the fluid line inside the pressure vessel. The plurality of holes fluidically connects the chamber and an interior passage of the fluid line. The fluid pulsation attenuator further includes a plurality of fibers inside the chamber. The plurality of fibers fills the chamber and surrounds the fluid line.
The fluid pulsation attenuator of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
the plurality of fibers comprises glass fibers;
the pressure vessel is elongated along a center axis and the fluid line is coaxial with the pressure vessel;
the fluid line comprises: an inlet extending axially from a first end of the pressure vessel; and an outlet extending axially from a second end of the pressure vessel opposite the inlet;
the plurality of holes is distributed on the fluid line inside the pressure vessel from the first end of the pressure vessel to the second end of the pressure vessel; and/or
the fluid line comprises: a first solid tube extending into the pressure vessel and forming the inlet of the fluid line; a second solid tube extending into the pressure vessel and forming the outlet of the fluid line; and a mesh tube inside the pressure vessel and connected between the first solid tube and the second solid tube.
In another embodiment, a fluid system includes a pump and a fluid pulsation attenuator fluidically connected to the pump. The fluid pulsation attenuator comprises a pressure vessel enclosing a chamber and a fluid line extending through the pressure vessel. A plurality of openings is formed in the fluid line inside the pressure vessel. The plurality of openings fluidically connects the chamber and an interior passage of the fluid line. The fluid pulsation attenuator also includes a cushion inside the chamber.
The fluid system of the preceding paragraph can optionally include, additionally and/or alternatively, any one or more of the following features, configurations and/or additional components:
the fluid pulsation attenuator is upstream from the pump;
the fluid pulsation attenuator is downstream from the pump;
the cushion is a pad that comprises fibers;
the pad fills the chamber and surrounds the fluid line;
the fibers comprise glass fibers;
the fluid line comprises: an inlet extending outward from the pressure vessel; and
an outlet extending outward from the pressure vessel opposite the inlet; and/or
the fluid line comprises: a first solid tube extending into the pressure vessel and forming the inlet of the fluid line; a second solid tube extending into the pressure vessel and forming the outlet of the fluid line; and a mesh tube inside the pressure vessel and connected between the first solid tube and the second solid tube.
Any relative terms or terms of degree used herein, such as “substantially”, “essentially”, “generally”, “approximately”, and the like, should be interpreted in accordance with and subject to any applicable definitions or limits expressly stated herein. In all instances, any relative terms or terms of degree used herein should be interpreted to broadly encompass any relevant disclosed embodiments as well as such ranges or variations as would be understood by a person of ordinary skill in the art in view of the entirety of the present disclosure, such as to encompass ordinary manufacturing tolerance variations, incidental alignment variations, transitory vibrations and sway movements, temporary alignment or shape variations induced by operational conditions, and the like.
While the invention has been described with reference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. For example, while
