Showing papers on "Volumetric flow rate published in 1976"

The interfacial drag and the height of the wall layer in annular flows

Abstract: A method to predict the height of the wall layer and the interfacial drag in annular flow under conditions that the flow rate of the entrained liquid is known is developed from measurements on air-water flow in circular tubes. Flow conditions are found to be characterized by a generalized Martinelli flow parameter.

Studies on multilayer film coextrusion I. The rheology of flat film coextrusion

Abstract: Multilayer blown film coextrusion was studied, both experimentally and theoretically. For the experimental study, an annular die with a feed-port system was designed and multilayer blown films were produced by rotating the inner mandrel with a one horsepower variable-speed drive at speeds from nearly 2 to 6 rpm, and by inflating the tubular molten film with air. The die has 16 feed slots and melt pressure transducers are mounted along the axial direction of the outer wall of the annular flow channel. The transducers were used to determine the pressure gradient in the annular flow channel, which then permitted determination of the reduction in pressure drop when different combinations of two polymer systems were coextruded. Polymers used for b own film coextrusion were: (1) low-density polyethylene with ethylene-vinyl acetate; (2) low-density polyethylene with high-density polyethylene; (3) low-density polyethylene with polypropylene; (4) high-density polyethylene with ethylene-vinyl acetate. For the theoretical study, stratified helical flow was analyzed using a power-law non-Newtonian model. A computational procedure was developed to predict the number of layers, layer thickness, and the volumetric flow rate as functions of certain processing variables (namely, the pressure drop in the die, and the angular speed of rotation of the inner mandrel of the die) and the rheological parameters of the individual polymers concerned. Comparison was made of the theoretical prediction of volumetric flow rate with experimental ones. Some representative results are presented of the theoretically predicted axial and angular velocity distributions, shear stress profiles, and shear rate profiles.

Liquid-to-particle mass transfer in fixed bed reactor with cocurrent gas-liquid downflow

Abstract: Mass transfer coefficient kls was measured over a range of flow rates of gas Ug= 0-100 cm.s-1 and liquid Ul=0.05-25 cm.s-1 in a column packed with spheres of three different diameters d=2.8-12.7 mm. The systems used were the dissolution of benzoic acid in water and diffusionlimited oxidation of brass with dichromate ion in sulfuric acid solution. The effect of Ug on kls is not found at all in gas continuous flow, is the greatest in pulse flow and becomes less significant again in dispersed bubble flow. The value of kls increases rapidly around the transition from gas continuous to pulse flow. The enhancement factor β (=kls in two-phase flow/kls in single-phase flow) increases from 1.2 to 2 with increasing d in gas continuous flow while it equals the reciprocal of liquid holdup in pulse and dispersed bubble flows. A liquid-film analogy in gas continuous flow and a single-phase analogy in pulse and dispersed bubble flows are proposed and the experimental results are examined in the light of them.

Automatically controlled desurging system

Abstract: A desurging system is placed in the fluid flow line near the output of a fluid pump to remove pressure fluctuations created in the flowing fluid by action of the fluid pump. The fluid passes through a gas-loaded, diaphragm type, fluid desurger. A gas volume control unit automatically controls the gas volume in the desurger by controlling both the gas-charging and the gas-discharging operations in response to measurements of the gas volume in the desurger and the gas flow rate into and out of the desurger. A diaphragm protection control unit is responsive to a measurement of the differential pressure across the diaphragm of the desurger to automatically bleed off the gas pressure in the desurger any time that such pressure exceeds the strength limitations of the diaphragm.

System for determining the ratio of oil to water in a metered fluid stream

Abstract: A system for metering a fluid stream constituted by a mixture of oil and water to determine the volumetric ratio of oil-to-water in the stream. The system includes a vortex meter through which the stream is conducted to produce a meter signal whose frequency depends on the volumetric flow and whose amplitude depends on the mass flow of the stream. Derived from the meter signal is a volumetric signal that is solely a function of frequency and a mass flow signal that is solely a function of amplitude, the volumetric signal being divided by the mass flow signal to produce a density signal. The volumetric and density signals are fed to a computer to which is also applied a temperature signal that depends on the temperature of the metered stream. The computer has stored therein the relationship between water density and temperature and that between oil density and temperature, and it functions in response to the signals applied thereto to determine the respective volumes of oil and water in the mixture.

Method and system for measuring flow rate

Abstract: Volumetric fluid flow in a cylindrical conduit is determined by measuring the average flow velocity of the fluid flowing through a chordal measuring path lying at a radial distance of 0.54R where R is the radius of the conduit. This average flow velocity is multiplied by constants related to the location of the chordal path and to the chordal path length. The average flow velocity measurement is made by the use of an ultrasonic flow meter having upstream and downstream transducers which define the chordal measuring path. Multiple measuring paths are preferred.

Method and apparatus for the production of reaction mixtures from liquid reaction components

Abstract: The instant invention is directed to a method and apparatus for measuring the proportion of undissolved gas in a liquid component for the production of foam materials, particularly, those based on polyurethane. The method is based on the equation of state of ideal gases (Boyle-Mariot Law: P .sup.. V = constant) at constant temperatures. The gas contained in a liquid component charged with gas increases its volume under expansion according to the above equation. The gas expansion causes expansion of the liquid gas mixture. The difference in the volumetric flow rate of the liquid, at two differing pressures, is therefore a measurement of the quantity of gas present in the liquid. The apparatus consists of one volumetric flow rate measurement unit connected upstream of a pressure drop unit, a second volumetric flow rate measurement unit connected downstream of the pressure drop unit and a differential value indicator connected to the first and second volumetric flow rate measurement units.

Method and apparatus for measuring fluid flow in small bore conduits

Abstract: Fluid flow in small bore conduits is measured and controlled utilizing a Doppler flowmeter to measure flow rate. The fluid is then passed through a static chamber in which sound speed in the fluid is measured by a velocimeter. The outputs of the flowmeter and the velocimeter are multiplied to correct the measured flow rate for errors due to its sound speed dependency. The corrected flow rate may be then used to control a pump to provide the desired flow rate.

Effects of Monomer Flow Rate, Flow Configuration, and Reactor Geometry on the Rate of Plasma Polymerization

Abstract: The effects of flow rate on the plasma polymerization of ethylene in an rf discharge were investigated using both a tubular and a bell-jar-type of reactor. Both reactors contained parallel plate internal electrodes. Experiments with the tubular reactor showed that both the total thickness of the deposit and its distribution in the axial direction were strong functions of the flow rate. At low flow rates the polymer thickness decreased in the flow direction, while at high flow rates the polymer thickness increased. Each of these observations is explained by a simple model of plasma polymerization. Using the bell-jar reactor, different monomer flow distribution configurations were tested to determine their effect on the distribution of polymer thickness. It was found that distribution or diffusion of the monomer inflow provided a more uniform film.

Behind casing water flow detection using pulsed neutron oxygen activation

Abstract: BEHIND CASING WATER FLOW DETECTION USING PULSED NEUTRON OXYGEN ACTIVATION (D#74,199-2F) ABSTRACT OF THE DISCLOSURE Measurement of the linear flow velocity and volume flow rate of undesired behind casing water flow is provided. A well tool having a 14 MEV pulsed neutron source is used to irradiate the earth formations behind well casing with bursts of high energy neutrons. This irradiation activates elemental oxygen nuclei comprising the molecular structure of the undesired flow. Dual spaced gamma ray detectors located above or below the neutron source detect the decay of unstable isotope nitrogen 16 produced by the oxygen activation in the time intervals between the neutron bursts. Background radiation due to prompt N-7 radiation is thus largely avoided. From the detected nitrogen 16 characteristic gamma rays the linear flow velocity of the undesired flow is determined. By combining this with an estimation of the distance R to the undesired flow region from the detectors, the volume flow rate V may be deduced. I

Mass flow sensor system

Abstract: A mass flow sensor system for measuring the flow rate of a fluid in a sensing tube at diverse angular attitudes. Output signal distortion is minimized by neutralizing the effects of convection forces. The sensing tube is formed as a by-pass coupled to a fluid conduit and includes a loop in the shape of a single-turn helix. Circulation of the fluid through the loop cancels gravity-induced convection forces caused by temperature gradients and significantly reduces sensitivity to attitude change. A center-tapped temperature-sensitive resistor coil is wound around the outer surface of the loop. The coil is heated, and the temperature differential between the ends of the coil, corresponding to rate of mass flow, is detected as a voltage output signal generated in an associated bridge circuit.

Method and apparatus for magnetic separation of particles in a fluid carrier

Abstract: Particles suspended in a fluid carrier are differentially separated by, first, grading the particles into fractions of equal settling rates and, second, separating the equal-settling particles of each fraction according to the magnetic susceptibilities of the particles. The particulate sample to be separated is passed through a two-path parallel flow system. In one path, the sample is selectively graded, by elutriation, into equal-settling fractions. Each such fraction then flows directly to the second path, where it crosses a magnetic field at a velocity proportional to its settling rate. Such proportionality between settling rate and flow velocity provides a residence time which ensures that the degree of deflection, in response to gravitational and magnetic forces, required for separate recovery of magnetic particles, on the one hand, and non-magnetic particles, on the other hand, will be attained within the active length of the magnetic field. Provision is made for simultaneous adjustment of the flow rates in the respective paths, thereby allowing selection among fractions of different settling rates while, at the same time, maintaining the desired flow rate proportionality between the two paths. The flow rates are also independently adjustable to provide for other flow requirements within the individual flow paths.

Hydro- and hemodynamic effects of catheterization of vessels. II. Model experiments comparing circular and annular lumen area reduction.

Abstract: Experiments and a simple theoretical analysis have been performed concerning the flow through circular (stenosis) and annular (catheter piece) lumen area reduction of rigid- and elastic-walled vessels. Both steady and pulsatile flow at various volumetric flow rates were investigated. A good agreement between the experimental and the analytical results has been found. A critical annular lumen area reduction exists on a par with the well-known critical stenosis. The strongest reduction in pressure and in volumetric flow rate was caused by the catheter pieces, compared with the stenoses. The per cent reduction in pulse mean pressure and in volumetric mean velocity at pulsatile flow was equal to the per cent reduction in pressure and volumetric mean velocity at steady flow. The influence of the geometrical shape of the stenoses and the catheter pieces is further discussed.

Fluidic flow and velocity sensor

Abstract: A flowmeter of the fluid oscillator type having a fluid jet which oscillates at a frequency indicative of flow rate. By elimination of wall attachment effects and use of a proportional type amplifier, the range of the flowmeter is substantially extended beyond the limit of turbulent flow conditions. Linearity is improved by use of a differential pressure type of fluid jet control and the range may be further extended by use of multiple amplifier stages.

Hydro-and hemodynamic effects of catheterization of vessels. I. An experimental model.

Abstract: A mechanical model for experiments on the influence on pressure and volumetric flow rate arising from catheterization is described. It is possible under controlled conditions to determine the static and dynamic pressure together with the volumetric flow rate as a function of flow type, repetition frequency, shape and amplitude of pressure surges in pulsatile flow, peripheral resistance, geometry and dimensions of a stenosis or a catheter, and physical properties of the vessel wall materials and of the fluid employed.

Arrangement for determining liquid and gas flow rates

Abstract: By means of sonic or ultrasonic energy, flow rate is determined as a linear function of the difference between two frequencies by taking measurements in the direction of flow and in the direction opposite thereto. Transducers are used alternately as generators and pickups. To this end, the transit time difference is determined by means of a phase detector, and the frequencies of two oscillators are readjusted in accordance with the results of the measurements. The difference frequency can be indicated and calibrated in flow rate, and the number of cycles can be counted, the flow volume being directly proportional thereto.

Dynamic Analysis of a Plate Heat Exchanger System

Abstract: This paper presents a systematic analysis of static and dynamic characteristics of plate heat exchangers having a number of heat transfer plates. There are various flow types in a plate heat exchanger system. The results are numerically compared under the condition that each flow rate of the hot- and cold-side fluids remains constant, respectively in any flow type. The significant results are : 1) In almost every flow type, the temperature effectiveness increases as the number of passages increases. 2) Dynamic responses may greatly depend on the relation between the inlet and outlet passages where each fluid flows in a counter- or a parallel current. 3) Series flow types where the inlet and outlet passage are adjacent and the flow is a countercurrent have the best statics and dynamics among all types when the number of passages is the same.

A low-cost tipping bucket flowmeter for overland flow and subsurface stormflow studies

Abstract: Details on the design, construction, calibration, performance and application of a low-cost tipping bucket flowmeter are given. The flowmeter consists of two balanced water-receiving units, which tip back and forth as they are alternately filled by water. With each tip, an electrical pulse is generated by activating a microswitch and the pulse is recorded by an event recorder. The flow rate is computed from the number of pulses recorded. Over the range of 1.4–13.6 liters/min the tipping bucket read approximately 3% lower than a calibrated rotameter. A sampling funnel can be installed in conjunction with the flowmeter to collect water samples for chemical analysis.

Behind casing water volume flow rate measurement using gamma ray spectral degradation

Abstract: BEHIND CASING WATER VOLUME FLOW RATE MEASUREMENT USING GAMMA RAY SPECTRAL DEGRADATION (D#74l5l7-F) ABSTRACT OF THE DISCLOSURE Measurement of the distance from a gamma ray detector to a gamma ray source for locating of a channel of undesired behind casing water flow in a producing well is provided. A relationship is given for the count rate ratio at a detector in two distinct energy regions of the gamma ray spectrum as a function of the distance from the gamma ray source. When counts of charac-teristic gamma rays due to the decay of radioactive nitrogen 16 produced by the activation of elemental oxygen nuclei comprising the molecular structure of undesired water flow are made then the distance R to such flow may be determined by means of the above relationship. This may then be inter-preted in terms of the volume flow rate V of the undesired water flow.

Means for controlling a solvent refining unit

Abstract: A solvent refining unit is controlled so that it has a maximum allowable solvent flow rate or a maximum allowable extract oil flow rate The temperature of the extract-mix in the refining tower, the flow rate of the charge oil, the flow rate of the solvent and the flow rate of the extract oil are sensed by sensors which provide corresponding signals A circuit provides signals corresponding to desired flow rates for the charge oil and the solvent and for a desired temperature for the extract-mix in the refining tower The refining unit is operated in accordance with the desired signals so as to achieve either a maximum allowable flow rate for the solvent or a maximum allowable flow rate for the extract oil, or a maximum allowable flow rate for the refined oil, or a reduced charge oil flow rate for a fixed refined oil flow rate

Flowmeter determining volumetric flow of liquids by pressure chamber - is used especially to measure milk flow in dairy installations

Abstract: The pressure chamber has fitted on it several outlet openings and vertical slits, so that by the number, vertical position and size of these openings a linear or other relation is approximated between the head of liquid and the volumetric flow. The outlet openings can be arranged in a vertical outlet pipe in such a way that the relation between head of liquid and volumetric flow can easily be varied by exchanging the outlet pipe. The head of liquid can be converted into a measuring signal by measuring the gravity of the liquid dammed up in the pressure chamber. The buoyancy can be measured.

Diffusion of polymer additives in a developing turbulent boundary layer

Abstract: The results of an experimental study of the diffusion of water and aqueous polymer when tangentially injected from a line shot into a 2-dimensional external turbulent boundary layer formed on a flat plate are presented. Concentration profiles were obtained by adding a tracer dye to the injected liquid and measuring the fluorescence, using a spectrophotometer, of samples taken from the flow field. Empirical equations describing the transverse and longitudinal concentration field for given injections and flow parameters are presented. The results show that turbulent diffusion of polymer solution is suppressed compared to that of water when the concentration at the wall is higher than 0.75 wppm (weight parts per million) but increased below this value. The data also confirm the deduction of others that a series of regions can be defined, and that their length is dependent on the injection concentration and flow rate. A universal concentration profile is described for the final region which is in agreement with the observations of others. (10 refs.)

Component flow rate measurement in two-phase systems

Abstract: Process and apparatus for accurately measuring the volume or mass flow rate of each component phase of a two-phase mixture. In particular, mixtures of crude oil and natural gas in changing proportions and having fluctuating differential flow velocities are encountered at the wellhead. The volume rate of flow of the oil and gas components are separately determined by temporarily isolating successive fractions of the mixture, determining the component proportions and the volume flow rate of each successive fraction and calculating the product thereof. Mass flow rate may be determined by incorporating the densities of the components into the calculation. Total throughput may be calculated by summing the products of the component proportion and the flow rate for all successive fractions.

Behind casing water volume flow rate measurement using concentric gamma ray detectors

Abstract: BEHIND CASING WATER VOLUME FLOW RATE MEASUREMENT USING CONCENTRIC GAMMA RAY DETECTORS (D#74,517-1-F) ABSTRACT OF THE DISCLOSURE Measurement of the distance from a gamma ray detector to a gamma ray source for location of a channel of undeisred behind casing water flow in a producing well is provided. Coaxially aligned dual cylindrical gamma ray detector crystals are used at one or more longitudinally spaced locations in the borehole to detect the characteristic gamma rays from the decay of radioactive nitrogen 16 pro-duced by the activation of elemental oxygen nuclei comprising the molecular structure of undesired water flow. The ratio of counts at the outer coaxial detector to those at the inner coaxial detector is then interpreted in terms of R, the dis-tance from the detector to the water flow channel. This dis-tance information may then be combined with the linear flow velocity of such undesired water flow to derive an indication of the volume flow rate V of such flow. I

Deposition of iron, nickel and iron-nickel layers from carbonyl vapors

Abstract: The rate of deposition of iron, nickel and iron-nickel layers from carbonyl vapors is shown to be controlled by diffusion across the gas phase boundary layer in contact with the heated substrate. At a constant flow rate the rate of deposition is shown to increase with increase in temperature up to a critical value above which the rate of deposition either remains constant (for high flow rates) or decreases (for low flow rates). This behavior is explained in terms of the thermal convection contribution to mass transfer in the reaction system. It is shown that the composition of alloy films produced from carbonyl mixtures at temperatures greater than 200°C (473 K) can be predicted to be approximately equal to the molar ratios of iron and nickel in the vapor phase when the carbonyls alone constitute the vapor phase. These predictions cannot be extended to situations where high dilution of the carbonyls in another gas is used, or to deposition temperatures of less than 200°C (473 K).