Balance drum for a rotating machine
A balance drum for a rotating machine includes an outer ring; an inner disk that includes a bore configured to receive a shaft; and a turbine assembly connected between an outer edge of the inner disk and an inner edge of the outer ring, the turbine assembly including a plurality of blades that extend between the outer edge and the inner edge and define a plurality of apertures therebetween.
1 . A rotating machine, comprising:
a housing that comprises a suction inlet and a discharge outlet, the housing defining a volume that comprises a flow path configured to transport a working fluid therethrough;
a shaft positioned in the volume and configured to couple to a prime mover and receive rotational force from the prime mover;
at least one impeller mounted on the shaft and configured to move the working fluid through the flow path based on the rotational force supplied to the shaft from the prime mover; and
a balance drum mounted on the shaft and configured to rotate with the shaft based on the rotational force supplied to the shaft from the prime mover, the balance drum comprising:
an outer ring,
an inner disk that comprises a bore configured to receive the shaft, and
a turbine assembly connected between an outer edge of the inner disk and an inner edge of the outer ring, the turbine assembly comprising a plurality of blades that extend between the outer edge of the inner disk and the inner edge of the outer ring and define a plurality of apertures therebetween, the balance drum configured to generate an axial thrust force based on a differential pressure between a first axial face of the balance drum and a second axial face of the balance drum opposite the first axial face of the balance drum caused by axially transporting the working fluid through the plurality of apertures of the turbine assembly; and
a balance line fluidly coupled between the suction inlet and a portion of the flow path adjacent the second axial face of the balance drum, the balance drum configured to conserve an amount of fluid power based on a flow of the working fluid through the plurality of apertures of the turbine assembly.
2 . The rotating machine of claim 1 , wherein the axial thrust force is opposite a rotor thrust force generated by the at least one impeller during rotation of the at least one impeller.
3 . The rotating machine of claim 1 , wherein the conserved amount of fluid power is defined by:
P
=
γ
*
Q
*
(
P
d
-
P
s
)
*
2
.
3
1
5
5
0
*
S
G
*
η
t
,
where P is the conserved amount of fluid power, γ is a specific weight of the working fluid, Q is a volumetric flow rate of the working fluid, P d is a pressure of the working fluid at the discharge outlet, P s is a pressure of the working fluid at the suction inlet, η t is an efficiency of the turbine assembly, and SG is a specific gravity of the working fluid.
4 . The rotating machine of claim 1 , wherein the plurality of blades comprise a plurality of airfoil blades.
5 . The rotating machine of claim 1 , wherein the working fluid comprises at least one of a hydrocarbon fluid, a gas, or a liquid.
6 . A method, comprising:
operating a rotating machine that comprises:
a housing that comprises a suction inlet and a discharge outlet, the housing defining a volume that comprises a flow path;
a shaft positioned in the volume and coupled to a prime mover;
at least one impeller mounted on the shaft; and
a balance drum mounted on the shaft, the balance drum comprising:
an outer ring,
an inner disk that comprises a bore that receives the shaft, and
a turbine assembly connected between an outer edge of the inner disk and an inner edge of the outer ring, the turbine assembly comprising a plurality of blades that extend between the outer edge of the inner disk and the inner edge of the outer ring and define a plurality of apertures therebetween;
transporting a working fluid through the suction inlet and into the flow path;
transporting the working fluid through the flow path with the at least one impeller based on a rotational force supplied to the shaft from the prime mover;
rotating the at least one impeller and the balance drum with the shaft based on the rotational force supplied to by the shaft from the prime mover;
transporting at least a portion of the working fluid axially through the plurality of apertures of the turbine assembly;
transporting the portion of the working fluid from the turbine assembly to one of the suction inlet or the discharge outlet;
generating, with the balance drum rotating with on the shaft, an axial thrust force based on a differential pressure between a first axial face of the balance drum and a second axial face of the balance drum opposite the first axial face of the balance drum caused by the transporting of the portion of the working fluid axially through the plurality of apertures of the turbine assembly; and
conserving an amount of fluid power based on the transporting of the portion of the working fluid axially through the plurality of apertures of the turbine assembly.
7 . The method of claim 6 , wherein the axial thrust force is opposite a rotor thrust force generated by the at least one impeller during rotation of the at least one impeller.
8 . The method of claim 6 , further comprising transporting the portion of the working fluid from the turbine assembly to the suction inlet through a balance line fluidly coupled between the suction inlet and a portion of the flow path adjacent the second axial face of the balance drum.
9 . The method of claim 6 , wherein the conserved amount of fluid power is defined by:
P
=
γ
*
Q
*
(
P
d
-
P
s
)
*
2
.
3
1
5
5
0
*
S
G
*
η
t
,
where P is the conserved amount of fluid power, γ is a specific weight of the working fluid, Q is a volumetric flow rate of the working fluid, P d is a pressure of the working fluid at the discharge outlet, P s is a pressure of the working fluid at the suction inlet, η t is an efficiency of the turbine assembly, and SG is a specific gravity of the working fluid.
10 . The method of claim 6 , wherein the plurality of blades comprise a plurality of airfoil blades.
11 . The method of claim 6 , wherein the working fluid comprises at least one of a hydrocarbon fluid, a gas, or a liquid.
12 . A balance drum for a rotating machine, the rotating machine comprising a housing that comprises a suction inlet and a discharge outlet, and the balance drum comprising:
an outer ring;
an inner disk that comprises a bore configured to receive a shaft; and
a turbine assembly connected between an outer edge of the inner disk and an inner edge of the outer ring, the turbine assembly comprising a plurality of blades that extend between the outer edge of the inner disk and the inner edge of the outer ring and define a plurality of apertures therebetween, wherein
the turbine assembly is rotatable with on the shaft in response to a rotational force supplied to the shaft from a prime mover,
the balance drum is configured to generate an axial thrust force in response to a differential pressure between a first axial face of the balance drum and a second axial face of the balance drum opposite the first axial face of the balance drum caused by axially transporting of a working fluid through the plurality of apertures of the turbine assembly, and
the balance drum is configured to conserve an amount of fluid power based on a flow of the working fluid through the plurality of apertures of the turbine assembly.
13 . The balance drum of claim 12 , wherein the axial thrust force is opposite a rotor thrust force generated by at least one impeller of the rotating machine.
14 . The balance drum of claim 12 , wherein the plurality of blades comprise a plurality of straight blades, and an efficiency of the turbine assembly is between 60% and 65%.
15 . The balance drum of claim 12 , wherein the conserved amount of fluid power is defined by:
P
=
γ
*
Q
*
(
P
d
-
P
s
)
*
2
.
3
1
5
5
0
*
S
G
*
η
t
,
where P is the conserved amount of fluid power, γ is a specific weight of the working fluid, Q is a volumetric flow rate of the working fluid, P d is a pressure of the working fluid at the discharge outlet, P s is a pressure of the working fluid at the suction inlet, η t is an efficiency of the turbine assembly, and SG is a specific gravity of the working fluid.
16 . The balance drum of claim 12 , wherein the plurality of blades comprise a plurality of airfoil blades.
17 . The rotating machine of claim 1 , wherein the plurality of blades comprise a plurality of straight blades.
18 . The rotating machine of claim 1 , wherein the at least one impeller comprises six impellers, and the suction inlet and the discharge outlet are oriented in opposed directions.