US3326163A

US3326163A - Centrifugal jet propulsion pump

Info

Publication number: US3326163A
Application number: US431109A
Authority: US
Inventors: Davis Hunt
Original assignee: Worthington Corp
Current assignee: Edison International Inc
Priority date: 1965-02-08
Filing date: 1965-02-08
Publication date: 1967-06-20
Anticipated expiration: 1984-06-20

Description

June 20, i967 H. DAVIS 3,326,163

CENTRIFUGAL JETA PROPULSION PUMP Filed Feb. 8, 1965 5 Sheets-Sheet l -"1 I l2 H @L l lll/111111111111111111111111!! HUNT DAVIS I N VEN TOR.

BY M. @um

.Emme 20, 19S? H. DAVIS 3,326,l63

CENTRIFUGAL JET PRoPuLsloN PUMP Filed Feb. e, 1965 s sheets-shew 2 FIGS FCT.7

HUNT DAVIS INVENTOR June 20, 1967 H. DAvls 3,326,163

CENTRIFUGAL JET PROPULSION PUMP Filed Feb. 8, 1965 5 Sheets-Sheet 5 HUNT DAVIS,

I N VEN TOR.

United States Patent C 3,326,163 CENTRIFUGAL JET PROPULSION PUMP Hunt Davis, Williamsville, N.Y., assigner to Worthington Corporation, Harrison, NJ., a corporation of Delaware Filed Feb. 8, 1965, Ser. No. 431,109 3 Claims. (Cl. 114-665) This invention relates generally to multi-stage, centrifugal, jet propulsion systems, and particularly, to pumps accommodated in a hydrofoil strut below the water level.

It is an object of the invention to provide a jet propulsion device for vessels whose eflciency is improved by reason of freedom from cavitation, and is dimensioned for inclusion in a hydrofoil strut.

It is another object of the invention to provide deeply submerged inlets for jet propulsion pumps which will avoid cavitation.

Yet another object of the invention is to provide a jet propulsion system with an engine that does not require speed-reduction gears between the prime mover and propulsion pumps.

A further object of the invention is to provide multiple stage of lightweight pumps, rather than a simple heavy pump that would outweigh the multiple stage pumps.

Another object of the invention is to use a hydrofoil strut for a housing for multi-stage pumps, so that an optimum eihciency, low friction strut form can be used, rather than the high friction, bulky strut which is necessary if a large single-stage pump is used.

Still a further object is to dispose the jet propulsion inlet opening, pump and discharge jet opening coaxially, below the water surface, to achieve minimum power loss resulting from flow through duets.

These objects and advantages, as well as other objects and advantages may be attained by the device shown by way of illustration of the inventive concept, in the drawings in which:

FIGURE l is a top, schematic view showing the location of the gas turbine and power turbine in a typical ve-ssel;

FIGURE 2 is a front elevational View of the vessel, and underwater structure;

FIGURE 3 is a rear elevational view of the vessel and underwater structure;

FIGURE 4 is a side elevational view of the vessel and underwater structure;

FIGURE 5 is a vertical sectional view of a housing or `strut including a multi-stage, jet-propulsion pump;

FIGURE l6 is a top schematic view of the multi-stage -pump in the housing;

FIGURE 7 is a partial, vertical, elevational view of the leading edge of the strut;

FIGURE 8 is a partial, vertical, elevational view of the trailing edge of the strut; and

FIGURE 9 is a perspective View of the multi-stage pump, connected to the intake and discharge outlet in the housing.

The propulsion of hydrofoil vessels by water-jets is not ecient if a single, large pump is used in an underwater strut; if the pump is instead located in the vessel, the circuitous course traversed by the water entails large power losses and the net positive suction head is seriously reduced. If the single, large pump is located in a strut or hydrofoil, the structure necessary to house the pump is so large as to entail excessive external drag. A construction in which many small pumps are connected in parallel, has been found to be capable of inclusion in a strut having a streamlined cross-section. Operating at high speed, with the pump shaft vertical, permits the use of intake and discharge ports for the pump far below the water line, with generally linear paths of intake and discharge -disposed in the same horizontal plane. Small pumps in parallel permit great weight reduction. For servicing and repair, the pump assembly may be conveniently removed in a vertical direction.

Referring now to the drawings in detail, a typical hydrofoil vessel 11, may be propelled by gas turbines 12, driving' power turbines 13. A forward strut 14 connected to the hull mounts a forward hydrofoil 15. Immediately below the gas turbines 13, rear struts 16 are attached to the hull. These struts jointly support a rear hydrofoil 17. Drive shafts 18, from the power turbines 13, pass through the hull downwardly through the rear struts 16. A stack of light weight, double-suction pumps 19 are located in each of the housings arranged in parallel to the driven by the shaft 18'. The

struts

14, 16, 16 have a generally streamline cross-section. The upper pump is provided with a mounting ange 26 for attachment to the hull.

The leading edge of the struts 16, has a plurality of suction openings 21. These openings 21 extend inwardly through suction-passages 31 in the struts 16 and terminate in a flange 10 for attachment to pump suction inlets 32. The pump suction inlets have anges 23 corresponding to the flanges 10, to which they may be detachably connected by bolts 24, or in some other suitable manner.

The trailing edge of the struts 16, has a plurality of discharge jet openings 25. These openings 25 extend inwardly through jet discharge passages 30v in the struts 16, and terminate in a flange 22, for attachment to the pump discharge outlets 26. The pump discharge outlets 26 have flanges 27 corresponding to the flanges 22, to which they may be detachably connected by bolts 24, or in some other suitable manner.

The suction openings 21 and the discharge jet openings 25 are located preferably near the bottom of the

struts

16, 16, so that when the vessel 11 rises on its

hydrofoils

15, 17, as shown in FIGURES 2, 3 and 4, the suction openings 21 will still be located well below the waterline providing maximum net positive suction head. The jet discharge openings 25, are similarly located, so that jet discharge is entirely below the water level during normal operation.

The suction openings 21 and the pump suction inlets 32, as well as the pump discharge outlets 26, and discharge jet openings 25 are preferably arranged so as to be as nearly in approximately the same horizontal plane as well as the same vertical plane as possible to obtain a straight, short flow path, to avoid power losse-s that arise in prior constructions where the ilow is directed to and from the pump through ducts and pipes of greater length and complexity.

The

flanges

22, 27, 10, 23 taper in a downward direction, as is shown in FIGURE 5. Thus, the pump assembly is removable vertically from the struts 16 for ease of installation, servicing and repair of the pumps.

The stack of small pumps in parallel, effectively reduces weight of the propulsion apparatus, eliminates the need for reduction gears and operates with a high degree of eficiency.

The foregoing description is merely intended to illustrate an embodiment of the invention. The component parts have been shown and described. They each may have substitutes which may perform a substantially similar function; such substitutes may be known as proper substitutes for the said components and may have actually been known or invented before the present invention; these substitutes are contemplated as being within the scope of the appended claims, although they are not specifically catalogued herein.

What is claimed:

1. In a 4marine craft having a buoyant hull and hydrofoils for supporting the hull above the surface of the water at operational speeds, the pump propulsion system comprising:

(a) a generally vertical strut having a streamlined cross-sectional conguration;

(b) a plurality of suction openings in the leading edge of the strut;

(c) a suction passage communicating with each suction opening;

(d) a plurality of discharge jet openings in the trailing edge of the strut;

(e) a discharge jet passage communicating with each discharge jet opening;

(f) a plurality of superposed pumps in the strut;

(g) a suction inlet of each pump connected to each suction passage;

(h) a discharge jet outlet of each pump connected to each discharge jet passage;

(i) the suction passages and the suction inlets each having opposing interconnected edges on their end portions lying in the same plane;

(j) the discharge jet passages and the discharge jet outlets each having opposing interconnecte-d edges on their end portions lying in the same plane.

2. The combination claimed in claim 1 wherein the plane in which the opposing interconnected edges of the suction passages and the suctionV inlets lie and the plane in which the opposing interconnected edges of the discharge jet passage and the discharge jet outlets lie diverge upwardly from each other.

5 3. The combination claimed in claim 1 wherein:

(a) the opposing interconnected edges of the suction passages and suction inlets are hanged and in registration with each other; and

(b) the interconnected edges on the end portions of discharge jet passages and discharge jet outlets are anged and in registration with each other.

References Cited UNITED STATES PATENTS 15 2,702,516 2/1955 Tinker 11S-16 3,006,307 10/1961 Johnson 114-665 3,143,097 8/1964 Meyerhoff 114-665 3,143,972 8/1964 Smith etal 115-16 FOREIGN PATENTS 286,776 8/1915 Germany.

MILTON BUCHLER, Primary Examiner.

25 ANDREW H. FARRELL, Examiner.

Claims

1. IN A MARINE CRAFT HAVING A BUOYANT HULL AND HYDROFOILS FOR SUPPORTING THE HULL ABOVE THE SURFACE OF THE WATER AT OPERATIONAL SPEEDS, THE PUMP PROPULSION SYSTEM COMPRISING: (A) A GENERALLY VERTICAL STRUT HAVING A STREAMLINED CROSS-SECTIONAL CONFIGURATION; (B) A PLURALITY OF SUCTION OPENINGS IN THE LEADING EDGE OF THE STRUT; (C) A SUCTION PASSAGE COMMUNICATING WITH EACH SUCTION OPENING; (D) A PLURALITY OF DISCHARGE JET OPENINGS IN THE TRAILING EDGE OF THE STRUT; (E) A DISCHARGE JET PASSAGE COMMUNICATING WITH EACH DISCHARGE JET OPENING; (F) A PLURALITY OF SUPERPOSED PUMPS IN THE STRUT; (G) A SUCTION INLET OF EACH PUMP CONNECTED TO EACH SUCTION PASSAGE; (H) A DISCHARGE JET OUTLET OF EACH PUMP CONNECTED TO EACH DISCHARGE JET PASSAGE; (I) THE SUCTION PASSAGES AND THE SUCTION INLETS EACH HAVING OPPOSING INTERCONNECTED EDGES ON THEIR END PORTIONS LYING IN THE SAME PLANE; (J) THE DISCHARGE JET PASSAGES AND THE DISCHARGE JET OUTLETS EACH HAVING OPPOSING INTERCONNECTED EDGES ON THEIR END PORTIONS LYING IN THE SAME PLANE.