Showing papers on "Nozzle published in 1968"

A Study of the Interaction of Gaseous Jets from Transverse Slots with Supersonic External Flows

Abstract: The paper describes a study concerning the sonic injection of a gaseous jet through a transverse slot nozzle in a wall into an external flow which is uniform outside of a turbulent boundary layer. An analytic model of the flowfield has been constructed in which conservation of momentum is applied to a control volume at the jet nozzle exit. A series of flat-plate experiments was conducted with normal, sonic jets at external flow Mach numbers of 2.61, 3.50, and 4.54. Pressure data near separation and the plateau were in agreement with existing correlations. Comparisons of the trends predicted by the analysis with two-dimensional force data from these experiments and from other sources showed good agreement. Values of amplification factor, the upstream interaction force plus the jet thrust divided by the vacuum thrust of a sonic jet, of 2.9 to 3.2 were measured. The amplification factor is relatively insensitive to variations in external flow Mach number and variations in injectant gas properties. A correlation of data obtained from experiments with finite-span slots demonstrates that the effective jet penetration height and the slot span are the important characteristic dimensions of such flowfields.

Adjustable turret spray nozzle

Abstract: A spray nozzle employed as a part of the crop-spraying system employed on a crop-spraying aircraft incorporating a rotatable plate having a plurality of orifices therein of different size for alignment with a discharge passage with the plate including one portion thereof which is imperforate to render the nozzle inoperative when desired. The structure for adjustably locking the nozzle plate in position includes a structure for causing the material discharged through the orifice to be discharged in a swirling pattern to provide efficient spraying of the material.

Thermal cutting apparatus and method

Abstract: Apparatus for subjecting a workpiece to the action of a laser beam comprises a nozzle and optical means for directing the laser beam at the workpiece through the nozzle, together with means for directing a gas stream at the workpiece through the same nozzle.

Indexable sprayer with plural nozzle orifices

Abstract: 1,211,068. Spray producers. SPRAYING SYSTEMS CO. 16 May, 1969 [4 June, 1968], No. 25206/69. Heading B2F. A nozzle assembly comprising nozzles 29, Fig. 1, and associated passages 31 in a plate 23, is prevented from being re-indexed to the inlet conduit 20 during the flow of fluid by the interaction of a bevelled projection 41 in a sealing and latching element 34 with a matching, bevelled, recessed annular surface 42 formed in the plate 23 around each of the passages 31, the projection being held firmly in position by the pressure of fluid against the rear surface of the element. The projection is otherwise lightly held against the surface 42 by a spring 38. When the nozzle assembly is rotated about the screw 25, the rear face of plate 23 moves the projection and element rearwardly until another passage 31 is in the indexing position. This rearward movement breaks the seal 40 between the element and plate, and enables pressure fluid to escape into an annular passage 44 from which it is taken off through bleed passages 43 directed in the same direction as the nozzle orifices. The nozzle tips 29 may be mounted between the plates 23 and 24, as shown. Alternatively, different styles and patterns of orifices may be formed in a single nozzle plate (51, Figs. 4 and 5, not shown). In the construction depicted in Fig. 6, the bevelled projection 71 cooperates with a correspondingly shaped recess 72 in the rear portion of each nozzle tip.

Metering of steam--water two-phase flow by sharp-edged orifices.

Abstract: This paper describes work conducted on the passage of steam-water mixtures through standard sharp-edged orifices for the prediction of flow conditions.When the stagnation enthalpy or alternatively ...

Base Pressure and Noise Produced by the Abrupt Expansion of Air in a Cylindrical Duct

Abstract: In the investigation described, the base pressure resulting from the abrupt expansion of an air jet from a circular nozzle into a concentric cylindrical duct or shroud has been measured. Stagnation pressure ratios of the forcing jet to atmospheric of up to six were used with shrouds of various lengths and diameters. As the primary or forcing jet pressure is increased and then decreased, the jet flow attaches and separates from the shroud wall and a hysteresis effect is exhibited by the pressure at the base of the shroud. With an attached flow, the base pressure attains a minimum value which depends mainly on the duct to nozzle area ratio and on the geometry of the nozzle, lower base pressures being obtained with convergent-divergent nozzles. When the jet pressure was increased beyond that required to attain the minimum value of the base pressure, it was observed that the ratio of the forcing jet pressure to base pressure remained constant.Noise measurements of the flow from the nozzle and shroud are prese...

Apparatus for washing patients hygienically

Abstract: The invention concerns apparatus for bathing a bedridden patient whereby washing medium continuously is supplied centrally through a pressure nozzle and after its use is sucked off peripherally through a suction nozzle arranged about the pressure nozzle.

Method and apparatus for spraying electrostatic dry powder

Abstract: Dry nonconductive powder passes from a hopper by means of a vibrating plate through an adjustable, nonclogging eductor and is directed by means of a current of air issuing through a rectangular orifice from a variable volume plenum chamber into a venturi. The powder particles pass into the entrance of the venturi in a stream of air having a rectangular flow pattern or cross section and from the venturi through a discharge nozzle and from the discharge nozzle onto a substrate to be coated. Corona wires are located in the proximity of the issuing end of the discharge nozzle so as to charge the powder particles in order to direct them onto a substrate. A positive draft is maintained downstream from the venturi entrance and serves to pick up excess powder particles which are pneumatically conveyed back to the feed hopper.

Transonic swirling flow.

Abstract: An approximation that can be used to determine how swirl affects the choking constraint on flow through the throat of a nozzle is obtained. The flow model is consistent with an experimentally observed flow pattern that contains a recirculating internal cell upstream of the throat. Results of the approximation are applied to three different flow situations. First, it is found that the choking constraint imposes a limit on the maximum tangential Mach number that can be achieved in a vortex tube even when an infinite pressure ratio is available. Next, analytic expressions are derived for the variation of rocket mass flow in a spinning rocket. The last application is the prediction of a performance curve for a fluidic vortex valve that is consistent with limited experimental data.

Vapor emission control system

Abstract: A vapor emission control system suitable for gasoline and other fuel delivery systems, adapted to eliminate the escape of fuel vapors to the atmosphere, and permit utilization of these vapors by the system. The disclosed embodiment of the control system includes a delivery conduit or line having a fuel delivery nozzle, an annular sealing means encircling the nozzle adapted to seal the nozzle within the opening to the container or tank, a vapor return line which may be vacuum operated, and a filter or other means adapted to store the vapors. In the disclosed embodiment of the nozzle assembly, the sealing means includes a flexible annular sleeve which is received within the container opening. The sleeve is expandable in one of the disclosed embodiments to seal the tank opening. In another embodiment, the sealing means is provided with a spring-tensioned annular sealing ring adapted to seal the opening to the tank. In the latter embodiment, the vapors are conducted through apertures in the sleeve to the vapor return line.

An analytical and experimental investigation of the velocities of particles entrained by the gas flow in nozzles

Abstract: Among the parameters which determine the erosion damage sustained by the walls of a nozzle in which a mixture of gas and particles is flowing, is the angle between the direction of the particle flow and the wall surface at the moment of impact. In this work an approximate analytical solution is made for a number of gas particle flows to determine broadly the features on which particle trajectory depends and some experimental results are given which confirm the theoretical computations. It is shown that the divergent region of a conical nozzle is unlikely to suffer a severe particle attack but that for parallel flow convergent-divergent nozzles the convex region near the exit may be affected. The choke, on the other hand, is most susceptible to particle attack even by fairly small particles. It may be said, in general, that any particle which enters the choke section with a velocity which, in the absence of effects from the gas would allow the particle to strike the choke wall, will in fact hit the wall at some point along the length of the choke.

The Dynamics of a Heated Free Jet of Variable Viscosity Liquid at Low Reynolds Numbers

Abstract: To spin polymers or glass into continuous fibers, molten material is forced through a nozzle into air forming a free liquid jet. The jet is cooled as it proceeds through the air and the cold fiber is collected on a rotating drum. The drum maintains tension on the jet causing it to attenuate as it cools. The behavior of a variable viscosity jet of glass was studied analytically and experimentally. In the analysis, it was assumed that the velocity and temperature distributions within the jet were one dimensional. Predictions of the jet shape, the temperature distribution and the tension in the jet as a function of the material properties and the process variables were obtained. Measurements of the jet shape and the tension distribution in the jet were made for various values of the flow rate, the collecting drum speed, and the nozzle temperature. The analytical predictions were found to be in error in the region of the jet within three to four nozzle diameters of the nozzle exit; below this point the theoretical and experimental results were in good agreement.

Exhaust plumes from nozzles with wall boundary layers.

Abstract: Numerical computations of exhaust plume flowfields from nozzles with boundary layers along the wall are presented. The problem is treated as the inviscid expansion of a shear flow around the nozzle lip, in a manner reminiscent of treatments of the near wakes of reentry vehicles. The low-Mach-number gas near the wall expands well beyond the limiting line calculated without boundary-layer effects, and "observables" such as dynamic pressure are greatly increased in the large-angle region over the values predicted for a frictionless nozzle flow. The distributions of dynamic pressure in the large-angle region are not greatly sensitive to the details of the boundary-layer profiles at the exit plane, although there is a noticeable difference in behavior between laminar and turbulent layers. Large-angle (up to 90-100°) effects of fully developed laminar or turbulent layers probably can be predicted to within a factor of 2 or 3, whereas there are order-of-magnitude differences from the flow with no boundary layer.

Hot runner system for plastic injection molds

Abstract: A HOT RUNNER SYSTEM HAVING A HOT RUNNER TUBE EXTENDING BETWEEN A SPRUE BUSHING AND A NOZZLE FITTING WHICH DIRECTS PLASTIC INTO THE MOLD CAVITY. THE TUBE IS SLIDABLE AT EACH END IN CLOSELY FITTING BORES IN THE SPRUE BUSHING AND NOZZLE FITTING, SO THAT HEAT EXPANSION OF THE TUBE WILL NOT PUSH ON AND TILE THE NOZZLE FITTING. IN ANOTHER EMBODIMENT, THE HOT RUNNER TUBE CONDUCTS PLASTIC DIRECTLY INTO A GATE LEADING INTO A MOLD CAVITY. THE TUBE HAS A TIP EXTENDING INTO THE GATE, AND THE TUBE CAN BE SLID BACK AND FORTH TO CONTROL THE FLOW AREA OF THE GATE.

Washer for parts and the like

Abstract: 1,255,106. Degreasing apparatus. SAFETYKLEEN CORP. Dec. 5, 1969 [Dec.6, 1968], No. 59457/69. Heading C7E. [Also in Division A4] A washer for removing e.g. grease from mechanical parts, comprises a sink 42, secured e.g. by welding, to the top flange 32 of a cylindrical filter 22 and a bracket 66 whereby a small opening is left at the top of the filter, the bracket supporting tube 96 carrying an electric motor and pump and a pump outlet pipe 90 leading to a hose 20 and nozzle 92 within the sink. Sink flange 58 carries an upright 84 with a fusible link 86 for supporting sink lid 16, hinged at 68, in the open position, the lid carrying a junction box 70 and switch 76 for electric leads leading to the pump and a lamp at the end of tube 72 for illuminating inside the sink. In use the pump and filter fit into the top of a standard drum lined with e.g. a polythene bag and containing solvent, the pump is switched on and the solvent sprayed over the parts, the solvent sinking through removable strainer, 56, through the filter via e.g. cotton wool 38 and perforations 36, back into the drum. The strainer may be closed and the parts soaked in the solvent in the sink. In case of fire, the fusible link breaks and allows the lid to close the sink.

Tank-washing apparatus

Abstract: 1,237,237. Tank washing apparatus. BUTTERWORTH SYSTEM Inc. 31 Oct., 1968 [19 Jan., 1968], No. 51613/68. Heading A4F. Apparatus for washing tanks includes a nozzle mechanism for spraying the interior of a tank and a control unit which is attached to and controls the nozzle mechanism in order to concentrate the spray on the dirtier areas of the tank, i.e. on sediment in the lower parts of the tanks. A nozzle 18 is mounted on sleeve 22 which is rotatable (through 360 degrees) about a pipe 19 connected to a supply of washing liquid, the nozzle 18 being rotatable (through 180 degrees) about an axis perpendicular to the axis of rotation of the sleeve 22. Control Unit. The unit, Fig. 5, is mounted on the nozzle mechanism outside the tank and a rotatable control shaft 24 extends from the unit through the pipe 19 and sleeve 22, the shaft 24 being attached to the sleeve 2 and being connected via a rod 32 to a rack 30 which moves up and down in accordance with up and down movement of the shaft 24 to rotate nozzle 18 via a pinion 28 and a hub 26. Rotational and up and down movement of the shaft 24 is transmitted from a screw 100 disposed within the unit, the screw passing through a nut 116 which may be held stationary or may be rotated. The screw 100 is rotated from a reversible motor 60 via a worm 84 and a gear 112, the screw then moving up and down through the stationary nut 116 so that both the sleeve 22 and the nozzle 18 rotate about their respective axes, this operating giving a coarse washing action. For fine washing action, the shaft 82 of worm 84 may be geared, via a clutch, to the shaft 94 of a worm 96 which rotates nut 116 in the same direction as screw 100 via gear 128. The gear ratio between the two shafts 82, 94 is such that the nut 116 rotates slower than screw 100. The gear ratio may be varied, and provision is made to rotate nut 116 manually. The screw 100 is provided at its upper end with a cam 140 which actuates three valves 144, 146, 142, any one of which may reverse motor 60 to rotate the screw 100 and nut 116 in the opposite direction. On reversal of the direction of rotation of the screw 100 there is a delay, e.g. of 90 degrees, provided by a lost-motion device, until the direction of rotation of nut 116 is reversed, thus giving a fine spray path from nozzle 18. Operation. Cam 140 moves from valve 142 until it actuates valve 144 to reverse motor 60 to move screw 100 downwardly, the cam 140 then passing valve 144 until it actuates valve 142 to again reverse motor 60 to move screw 100 upwardly until cam 140 actuates valve 146 to again reverse motor 60. Cam 140 then travels between valves 146 and 142 until washing is complete. Valve 146 may be adjusted vertically so that initial movement of cam 140 between valves 142 and 144 rotates nozzle 18 through 180 degrees and subsequent movement of cam 140 between valves 142 and valve 146 rotates nozzle through an angle of less than 180 degrees depending upon the position of valve 146. Washing is then concentrated on the dirtier lower part of the tank. A control circuit, Fig. 16 (not shown), incorporating valves 144, 146, 142 and motor 60 is illustrated. A number of these apparatuses may be provided in one tank.

Method for the high velocity liquid jet cutting of soft materials

Abstract: 1,242,930. Cutting by liquid jet. N. C. FRANZ. 26 Sept, 1969 [1 Oct., 1968], No. 47407/69. Heading B4B. [Also in Division F1] A method of cutting soft material by a high velocity liquid jet comprises selecting a suitable soft material e.g. cardboard, or nylon or cotton fabric, which heats at the edges of the cut due to the passage of the liquid therethrough, providing a high velocity liquid jet with sufficient energy to cut through the material as it is fed through the jet to produce cutting at a rate such that the jet liquid retained at the point of cut volatilizes from the cut within a short period of time due to the heating of the point of cut by the high velocity liquid jet. The apparatus for producing the high velocity jet comprises an hydraulic pump 12 driven from an electric motor 11 and feeding liquid from a reservoir 15 to one or other side of a piston 18a via a relief valve 16 and four-way valve 17. The piston 18a is provided with a ram 19 movable in a cell 20 into which the liquid, such as water, is fed; the liquid passes from the cell to a nozzle 22 via a two-way valve 21. The material is mounted on a table 24 having an opening for the passage of the jet and moved at a selected speed by means 25, 26. Various examples of the material, jet pressure and nozzle sizes and feed speed are described.

Performance of annular plug and expansion-deflection nozzles including external flow effects at transonic Mach numbers

Abstract: Performance evaluation of annular plug and expansion-deflection nozzles including external flow effects at transonic Mach numbers

Extruder nozzle for producing plastic foils

Abstract: A nozzle for producing foils from plastic material, preferably thermoplastic synthetic plastic material, has a flow passage lengthwise of the casing of the nozzle. The passage defines at one end a wide exit slit and at the other end a feed port of annular configuration. Meshing gears of a gear pump interposed intermediate the exit slit and the feed port drive the plastic material through the flow passage and toward the exit slit. The widths of the slit, the gears and the flow passage are such that the flow of plastic material between the gears and the exit slit is of substantially uniform width whereby a substantially uniform gauge and strength characteristics of the foil across its width are obtained.

Visualization of Noise from Cold Supersonic Jets

Abstract: The acoustic field of small, cold supersonic jets has been studied by shadowgraph visualization. Preliminary experiments showed the importance of choosing an optimum film position for the visualization of sound waves. The interpretation of shadowgraphs is discussed. The apparent radiation field from the supersonic region of the flow is of relatively high frequency. In this field the order of dominance of the sound sources in the present case is (i) radiation from the nozzle, (ii) radiation from shock‐turbulence interaction in the flow, and (iii) Mach‐wave radiation. When the jet flow is deflected, the jet‐deflector interaction becomes the principal noise source. The significance of the nozzle radiation is believed to result from the small scale of the jet used and demonstrates the necessity for care when extrapolating model scale acoustic data. The comparative in significance of Mach‐wave radiation is probably due to the lower exhaust velocity of the cold jets. It is suggested that Mach reflection of spherical waves may be an important factor in the generation of “Mach waves.”

Multinozzle system for vortex burners

Abstract: A nozzle to be positioned around a fuel atomizer between a rotary air chamber and a coaxial combustion chamber. The nozzle consists of a 45* conical frustum surrounding the atomizer but spaced therefrom, and at least one frustoconical baffle with the same cone angle, located between the outer frustum and the atomizer. Thus are defined two concentric, converging annular passageways through which rotating air passes from the air chamber into the combustion chamber around the atomizer.

Remotely controllable fire fighting apparatus

Abstract: A remotely controllable, boom-supported water delivery monitor and nozzle assembly particularly adapted for fire-fighting apparatus, and having independently operable nozzle sweep and vertical travel functions, and remotely controllable flow rate adjustment and spray pattern adjustment, all hydraulically operable from a remote control panel.

On the Characteristics of Divided Flow and Confluent Flow in Headers

Abstract: Formulas for calculating the flow rate ratio of each branch pipe are derived taking the diffuser effect on divided flow and the nozzle effect on confluent flow which is caused by branching streams in a header into consideration. Effects of the divided flow factor σD and of the confluent flow factor σo in those formulas on the flow rate ratio of each branch pipe are evaluated from the experimental results for water. The factors σD and σo are dimensionless numbers given by [numerical formula] where ησ is the diffuser factor which represents the pressure recovery factor due to branching of the fluid from a header, ψn is the nozzle factor due to adding of the fluid from branch pipes into a header, (ζ+λι/d) and m are the resistance coefficient of branch pipe and the ratio of crosssectional area of the header to one of the branch pipe respectively. A method for calculating the flow rate ratio of each branch pipe in the case where the inlet or the outlet of header is placed between both closed ends of the header is also presented.

Method for shielding a gas effluent

Abstract: 1,253,298. Spray producers. UNION CARBIDE CORP. 15 Jan., 1969 [16 Jan., 1968], No. 2368/69. Heading B2F. [Also in Divisions C6, C7, H3 and H5] A nozzle comprises a central orifice through which a gaseous effluent can flow, surrounded by an annular coaxial orifice through which an inert gas can be forced such that in operation the inert gas forms an uniformly turbulent annular stream with a width W measured in inches of from 0.25 to 4.0 times the square root of the diameter D 0 of the central orifice measured in inches. In operation the longitudinal momentum flux of the stream is greater than 2.0 1b¢/sec ft¢ as given by the expression (Q/A)P ¢ where Q is the flow rate in ft 3 /sec of the annular stream, A is the annular area in ft 2 and p is the density of the gas in 1b/ft 3 . The nozzle may be used in a plasma spray gun.

Turbine stator cooling control

Abstract: The stator of a gas turbine includes an arrangement for controlling flow of cooling air to the vanes of the second stage turbine nozzle from the engine compressor. Control is by a valve defined by two rings extending around the exterior of the turbine nozzle which have different coefficients of thermal expansion so that the gap between them varies in accordance primarily with the temperature of the cooling air which tends to increase with the power output of the engine and thus with the need for cooling air.

Automatic trip safety fill nozzle

Abstract: A safety automatic trip fluid dispensing nozzle for cooperatively sealing a tank fill pipe to prevent fluid slashage and vapor emission in which a valve mechanism with an operating linkage is preconditioned for valve mechanism operation upon fill pipe sealing and for valve mechanism deactuation upon unseating intentionally or inadvertently or upon increased fill pipe pressure transmitted to the dispensing nozzle beyond a predetermined pressure level.