Inlet ramps for pressure exchange devices

Abstract

A system includes a rotary isobaric pressure exchanger (IPX) having an oblique ramp disposed within a fluid inlet of an end cover at an oblique angle configured to direct a fluid toward an interior surface of a channel within a rotor to facilitate rotation of the rotor. In addition, the system may include one or vanes disposed within the fluid inlet to further direct the fluid toward the interior surface. Further, the system may include one or more passages extending from the fluid inlet toward a surface of the end cover that interfaces with the rotor, where the one or more passages utilize the fluid to apply additional force to the rotor to facilitate rotation.

1 . A rotary isobaric pressure exchanger (IPX) for transferring pressure energy from a high pressure first fluid to a low pressure second fluid, comprising:
 a cylindrical rotor configured to rotate circumferentially about a rotational axis and having a first end face and a second end face disposed opposite each other with a plurality of channels extending axially therethrough between respective apertures located in the first and second end faces;   a first end cover having a first surface that interfaces with and slidingly and sealingly engages the first end face, wherein the first end cover has at least one first fluid inlet and at least one first fluid outlet that during rotation of the cylindrical rotor about the rotational axis alternately fluidly communicate with at least one channel of the plurality of channels, wherein the first end cover comprises a first oblique ramp disposed within the at least one first fluid inlet, and the first oblique ramp is configured to direct a first fluid at a first oblique angle relative to the rotational axis into one or more channels of the plurality of channels; and   a second end cover having a second surface that interfaces with and slidingly and sealingly engages the second end face, wherein the second end cover has at least one second fluid inlet and at least one second fluid outlet that during rotation of the cylindrical rotor about the rotational axis alternately fluidly communicate with at least one channel of the plurality of channels, wherein the second end cover comprises a second oblique ramp disposed within the at least second fluid inlet, and the second oblique ramp is configured to direct a second fluid at a second oblique angle relative to the rotational axis into one or more channels of the plurality of channels;   a first vane disposed within the first fluid inlet, the second fluid inlet, or at least one channel of the plurality of channels, wherein the first vane is disposed at a third oblique angle relative to the rotational axis; and   wherein the first oblique ramp and the second oblique ramp are configured to direct the first fluid and the second fluid, respectively, at the first oblique angle and the second oblique angle to impart a force against an interior surface of a respective channel of the plurality of channels to further circumferential rotation of the cylindrical rotor, and the first vane is configured to direct the first fluid or the second fluid to impart an additional force against the interior surface of the respective channel of the plurality of channels to further circumferential rotation of the cylindrical rotor.   
     
     
         2 . The rotary IPX of  claim 1 , wherein the first vane is disposed on a surface of the first oblique ramp. 
     
     
         3 . The rotary IPX of  claim 1 , wherein first vane is disposed on a surface of the second oblique ramp. 
     
     
         4 . The rotary IPX of  claim 1 , wherein the first vane is disposed on surface of the at least one channel. 
     
     
         5 . The rotary IPX of  claim 1 , comprising a first vane disposed on a first surface of the first oblique ramp, a second vane disposed on a second surface of the second oblique ramp, and a third vane disposed on a third surface of the at least one channel. 
     
     
         6 . The rotary IPX of  claim 1 , wherein at least one of the first fluid inlet, the first fluid outlet, the second fluid inlet, and the second fluid outlet comprises a cross-sectional shape along a plane orthogonal to the rotational axis, and the cross-sectional shape comprises a central shaft coupled to a first lobe at a first end and a second lobe at a second end. 
     
     
         7 . The rotary IPX of  claim 6 , wherein each of the first fluid inlet, the first fluid outlet, the second fluid inlet and the second fluid outlet comprises the cross-sectional shape having the central shaft coupled to the first lobe and the second lobe. 
     
     
         8 . The rotary IPX of  claim 1 , wherein the first end cover comprises a first passage extending from the first fluid inlet upstream of the first surface to the first surface, and the first passage is configured to inject the first fluid against a first respective interior surface of one the channels of the plurality of channels to impart a further additional force to further circumferential rotation of the cylindrical rotor. 
     
     
         9 . The rotary IPX of  claim 8 , wherein the first passage comprises a first cross-sectional area and the first fluid inlet comprises a second cross-sectional area, and the second cross-sectional area is greater than the first cross-sectional area. 
     
     
         10 . The rotary IPX of  claim 8 , wherein the first passage is disposed at a third oblique angle relative to the first fluid inlet. 
     
     
         11 . The rotary IPX of  claim 8 , wherein the second end cover comprises a second passage extending from the second fluid inlet upstream of the second surface to the second surface, and the second passage is configured to inject the second fluid against a second respective interior surface of one the channels of the plurality of channels to impart a further additional force against the second respective interior surface to further circumferential rotation of the cylindrical rotor. 
     
     
         12 . The rotary IPX of  claim 1 , wherein the rotary IPX is configured to be utilized with a frac system, and the first fluid comprises a proppant free fluid and the second fluid comprises a frac fluid having proppants. 
     
     
         13 . A rotary isobaric pressure exchanger (IPX) for transferring pressure energy from a high pressure first fluid to a low pressure second fluid, comprising:
 a cylindrical rotor configured to rotate circumferentially about a rotational axis and having a first end face and a second end face disposed opposite each other with a plurality of channels extending axially therethrough between respective apertures located in the first and second end faces;   a first end cover having a first surface that interfaces with and slidingly and sealingly engages the first end face, wherein the first end cover has at least one first fluid inlet and at least one first fluid outlet that during rotation of the cylindrical rotor about the rotational axis alternately fluidly communicate with at least one channel of the plurality of channels, wherein the first end cover comprises a first oblique ramp disposed within the at least one first fluid inlet, and the first oblique ramp is configured to direct a first fluid at a first oblique angle relative to the rotational axis to impart into one or more channels of the plurality of channels; and   a second end cover having a second surface that interfaces with and slidingly and sealingly engages the second end face, wherein the second end cover has at least one second fluid inlet and at least one second fluid outlet that during rotation of the cylindrical rotor about the rotational axis alternately fluidly communicate with at least one channel of the plurality of channels, wherein the second end cover comprises a second oblique ramp disposed within the at least second fluid inlet, and the second oblique ramp is configured to direct a second fluid at a second oblique angle relative to the rotational axis into one or more channels of the plurality of channels;   a first passage disposed within the first end cover extending from the first fluid inlet upstream of the first surface to the first surface; and   wherein the first oblique ramp and the second oblique ramp are configured to direct the first fluid and the second fluid, respectively, at the first oblique angle and the second oblique angle to impart a force against an interior surface of a respective channel of the plurality of channels to further circumferential rotation of the cylindrical rotor, and the first passage is configured to inject the first fluid against a respective interior surface of one the channels of the plurality of channels to impart an additional force to further circumferential rotation of the cylindrical rotor.   
     
     
         14 . The rotary IPX of  claim 13 , wherein the rotary IPX is configured to be utilized with a frac system, and the first fluid comprises a proppant free fluid and the second fluid comprises a frac fluid having proppants. 
     
     
         15 . The rotary IPX of  claim 13 , wherein the first passage comprises a first cross-sectional area and the first fluid inlet comprises a second cross-sectional area, and the second cross-sectional area is greater than the first cross-sectional area. 
     
     
         16 . The rotary IPX of  claim 13 , wherein the first passage is disposed at a third oblique angle relative to the first fluid inlet. 
     
     
         17 . The rotary IPX of  claim 13 , wherein the second end cover comprises a second passage extending from the second fluid inlet upstream of the second surface to the second surface, and the second passage is configured to inject the second fluid against a second respective interior surface of one the channels of the plurality of channels to impart a further additional force to further circumferential rotation of the cylindrical rotor. 
     
     
         18 . The rotary IPX of  claim 13 , wherein at least one of the first fluid inlet, the first fluid outlet, the second fluid inlet, and the second fluid outlet comprises a cross-sectional shape along a plane orthogonal to the rotational axis, and the cross-sectional shape comprises a central shaft coupled to a first lobe at a first end and a second lobe at a second end. 
     
     
         19 . The rotary IPX of  claim 18 , wherein each of the first fluid inlet, the first fluid outlet, the second fluid inlet and the second fluid outlet comprises the cross-sectional shape having the central shaft coupled to the first lobe and the second lobe. 
     
     
         20 . The rotary IPX of  claim 13 , comprising a first vane disposed within the first fluid inlet, the second fluid inlet, or at least one channel of the plurality of channels, wherein the first is disposed at a third oblique angle relative to the rotational axis, and the first vane is configured to direct the first fluid or the second fluid to impart a further additional force against the interior surface of the respective channel of the plurality of channels to further circumferential rotation of the cylindrical rotor. 
     
     
         21 . The rotary IPX of  claim 20 , wherein the first vane is disposed on a surface of the first oblique ramp. 
     
     
         22 . The rotary IPX of  claim 20 , wherein first vane is disposed on a surface of the second oblique ramp. 
     
     
         23 . The rotary IPX of  claim 20 , wherein the first vane is disposed on surface of the at least one channel. 
     
     
         24 . The rotary IPX of  claim 20 , comprising a first vane disposed on a first surface of the first oblique ramp, a second vane disposed on a second surface of the second oblique ramp, and a third vane disposed on a third surface of the at least one channel. 
     
     
         25 . A method for determining an oblique angle of an oblique ramp disposed within a fluid inlet of an end cover of a rotary isobaric pressure exchanger (IPX) that transfers pressure energy from a high pressure first fluid to a low pressure second fluid, the end cover having a surface that interfaces with and slidingly and sealingly engages an end face of a cylindrical rotor of the rotary IPX, and the oblique ramp is configured to direct the first fluid or the second fluid at the oblique angle to impart a force against an interior surface of a respective channel of a plurality of channels disposed within the cylindrical rotor to further circumferential rotation of the cylindrical rotor, comprising:
 determining a desired axial acceleration profile of a dynamic fluid interface between the first fluid and the second fluid within the respective channel utilizing a model;   integrating the desired axial acceleration profile with respect to time to determine an axial velocity profile for the dynamic fluid interface through the respective channel;   comparing the desired axial acceleration profile to the axial velocity profile for correspondence;   integrating the axial velocity profile with respect to time to determine a position profile of the dynamic fluid interface within the respective channel when the desired axial acceleration profile corresponds to the axial velocity profile;   comparing the axial velocity profile to the position profile for correspondence; and   calculating the oblique angle of the oblique ramp when the axial velocity profile corresponds to the position profile so that the oblique angle reduces mixing of the first and second fluids at the dynamic fluid interface while generating sufficient torque on the cylindrical rotor to circumferentially rotate the cylindrical rotor.