Hydrokinetic amplifier with high momentum transfer coefficient
BACKGROUND 
     Hydrokinetic amplifiers, such as explained in U.S. patent application Ser. No. 612,742, filed May 21, 1984, entitled HYDROKINETIC AMPLIFIER, far surpass injectors in their ability to transfer momentum from vapor to liquid for increasing the liquid pressure. Momentum transfer coefficients for injectors have ranged up to about 0.5, and hydrokinetic amplifiers have increased this coefficient to more than 0.6, thereby more than doubling the pressure gain achieved by injectors. 
     I have discovered a way that hydrokinetic amplifiers can further increase the coefficient of momentum transfer to at least 0.8. This makes hydrokinetic amplifiers operate even more efficiently and achieve an even higher pressure gain between liquid input and output. It also expands the potential uses for hydrokinetic amplifiers. 
     SUMMARY OF THE INVENTION 
     I have discovered that vapor accelerated to a high velocity can transfer more momentum to a liquid jet by impinging on both the inner and outer surfaces of an annular liquid jet entering the acceleration chamber of a hydrokinetic amplifier. By keeping the liquid away from the acceleration chamber wall and balancing the liquid and vapor flows, the liquid jet can be made to converge from annular to cylindrical as it accelerates toward the diffuser. As the liquid jet converges, it captures all the momentum of a high velocity vapor stream entering the annular interior of the liquid jet, while the liquid also receives substantial momentum from an outer vapor stream that helps keep the liquid clear of the acceleration chamber wall. Accelerating both vapor streams to supersonic velocity can raise vapor momentum to a high value, and impinging both the inner and outer vapor streams against the liquid jet can transfer at least 80% of the vapor momentum to the liquid, accelerating the liquid to a high velocity producing a high liquid pressure gain. 
     Two or more annular liquid jets with different diameters can be arranged concentrically with high velocity vapor streams directed both within and around each annular liquid jet. Multiple liquid jets can converge and merge to a single liquid stream as they pass through the acceleration chamber, converting to liquid velocity all the momentum of the vapor streams within the liquid jets and subjecting only the outermost vapor stream to some friction loss along the converging wall of the acceleration chamber. The flow rates of the liquid and vapor streams can be adjusted to ensure maximum condensation, maximum momentum transfer, and complete liquid merger upon reaching the diffuser, which efficiently converts liquid velocity to pressure. 
    
    
     DRAWINGS 
     FIG. 1 is a schematic view of a preferred embodiment of a hydrokinetic amplifier having a high momentum transfer coefficient; and 
     FIG. 2 is a schematic view of a multi-liquid jet embodiment of a hydrokinetic amplifier having a high momentum transfer coefficient. 
    
    
     DETAILED DESCRIPTION 
     Hydrokinetic amplifier 10, as schematically shown in FIG. 1, includes an acceleration chamber 13 having an outer wall 19 converging from an ingress region 14 to an egress region 16, downstream from which a diffuser 15 extends. Vapor accelerates liquid through acceleration chamber 13 as described in U.S. patent application Ser. No. 612,742 for hydrokinetic amplifiers in general, from which hydrokinetic amplifier 10 differs primarily in liquid and vapor inputs. 
     Liquid inbound to amplifier 10 enters an annular path 30 leading to a converging region 31 of an annular liquid input nozzle 11. Liquid nozzle 11 efficiently converts liquid pressure to velocity and discharges an annular liquid jet 20 into ingress region 14 of acceleration chamber 13. Liquid nozzle 11 is also spaced inward from converging wall 19 of acceleration chamber 13 so that liquid in jet 20 remains out of contact with wall 19 while it accelerates from ingress region 14 to egress region 16. 
     Vapor inbound to amplifier 10 is either drawn from two different vapor sources or divided from a single source into two flows along an inner vapor path 41 and an outer vapor path 42 as schematically illustrated. Inner path 41 leads to the interior of annular liquid path 30 and to an inner vapor nozzle 50, and outer path 42 leads to an outer vapor nozzle 60 annularly surrounding liquid nozzle 11. 
     Vapor nozzle 50 has a throat region 51 providing a minimum cross-sectional area arranged upstream from the discharge region of liquid nozzle 11. Downstream from throat region 51, vapor nozzle 50 has an expanding region 52 of increasing cross-sectional area through which vapor accelerates into ingress region 14. 
     Incoming vapor preferably reaches sonic velocity in throat region 51 and supersonic velocity in expansion region 52, and vapor nozzle 50 preferably produces maximum vapor thrust so that vapor from inner nozzle 50 is traveling as fast as possible when it impinges on the inside surface of annual liquid jet 20. As this occurs, substantially all of the momentum of the speeding vapor transfers to the liquid in jet 20, causing it to accelerate toward egress region 16. Vapor condensing in the liquid also collapses, reducing the vapor volume to make room for more vapor speeding into and impinging on the diminishing cone of the inner surface of liquid jet 20. 
     Vapor in outer path 42 flows through an annular outer vapor nozzle 60, which also has a throat region 61 with a minimum cross-sectional area and an expanding region 62 with an enlarging cross-sectional area leading to a discharge at ingress region 14. Outer vapor nozzle 16 also is preferably designed for maximum thrust so that vapor can accelerate from sonic velocity in throat region 61 to supersonic velocity in expansion region 62 before merging with liquid in jet 20 at ingress region 14. 
     The outer vapor stream from annular nozzle 60 surrounds annular liquid jet 20 and flows between jet 20 and the converging wall 19 of acceleration chamber 13. In this location, the outer vapor stream not only impinges on and accelerates the liquid in jet 20, but also helps keep liquid out of contact with acceleration chamber wall 19 so as to minimize fluid friction losses. 
     Flow rates through vapor nozzles 50 and 60 are preferably adjustable so that liquid jet 20 can receive and condense vapor at the fastest rate possible from both the inner and outer vapor streams without blowing apart or running into contact with acceleration chamber wall 19. Adjusting or balancing flow rates through vapor nozzles 50 and 60 and liquid nozzle 11 can make annular liquid jet 20 converge in a generally conical flow and merge to a solid liquid stream as it enters egress region 16. The many possible ways available in the art of regulating vapor flow rates are schematically illustrated by vapor valve 45. 
     Substantially all of the vapor from inner nozzle 11 and at least about 90% of the total inflowing vapor condenses in and accelerates the liquid stream 20 before the fluid flow passes into diffuser 15. The minimum cross-sectional area of diffuser 15 at egress region 16 is dimensioned to be up to about 10% larger than the cross-sectional area of the through-flowing liquid. 
     Hydrokinetic amplifier 70 of FIG. 2 schematically shows to annular and concentric liquid jets 20a and 20b. These are discharged from concentric annular liquid nozzles 11a and 11b and receive high velocity vapor from respective inner vapor nozzles 50a and 50b and outer vapor nozzle 60 surrounding outer liquid nozzle 11b. Such an arrangement captures all the momentum of the expanding vapor from inner nozzles 50a and 50b, along with a substantial portion of the momentum of the vapor from outer vapor nozzle 60. 
     More than two concentric annular liquid jets can also be used for capturing the momentum of multiple interior vapor streams. Only the exterior vapor stream around the outermost liquid jet experiences friction losses along acceleration chamber wall 19.