Showing papers on "Volumetric flow rate published in 1974"

Liquid flow through aligned fiber beds

Abstract: The influence of surface properties on the flow of fluids, including epoxy resin, through aligned glass and other fiber beds has been examined. The observed flow rates were higher than those predicted from the Kozeny-Carman equation, and were influenced by the surface properties of the fluid used. This is attributed to variations in the distribution of porosities and to the presence of air bubbles trapped during the initial wetting of the bed. The implications of these findings to the preparation of composites are discussed.

Flow and time proportional sampling system

Abstract: A sampling system for drawing samples from a fluid flow which is responsive to manual actuation, predetermined increments of flow volume, or predetermined increments of time. The system includes a flow meter and a flow sampler interconnected and physically located in the vicinity of the flow being monitored. The flow meter converts the flow head to flow rate and subsequently to flow volume. The head to flow conversion is mechanical and provides for flow measurement through a flow channel having a given cross section shape over a wide range of shape sizes by means of an electrical adjustment. The flow meter provides for flow measurement through flow channels having varying cross secton shapes by means of selectively engaging a predetermined one of a plurality of cams designed to convert head to flow is being measured. The sampler is electrically connected to the flow meter for use in the sample per flow volume mode and provides for a constant volume sample which is independent of flow head, sampler height above the flow surface, power source voltage level, pumping time or any of the other variables which heretofore affected the sample volume. Automatic sequencing within the sampler provides for purging the system, drawing the sample from the flow, sizing the sample, depositing the sample in a storage container, and purging the sampler intake after storage. Means are provided for depositing a predetermined number of samples in each of a plurality of storage containers, or for utilizing a predetermined number of containers for holding each sample, and for de-energizing the sampler until manually attended after a predetermined number of storage containers have received samples. The automatic internal sampler sequencing is initiated by an input signal which is generated by either a flow or time proportional sensor or manual actuation according to control selection.

Absorption process method and apparatus

Abstract: The flow rate of feed material containing a constituent to be absorbed and the flow rate of the absorption medium entering an absorption zone are controlled in response to the content and flow rate of feed material entering the absorption zone and the amount of a desired bottoms constituent in the overhead stream of the absorption zone so that the efficiency of the absorption process is optimized. Under circumstances necessitating maximum production from the absorption zone and its associated stripping zone, the absorption medium flow rate is maintained at a maximum value and the feed flow rate is controlled in response to feed composition and flow as well as the concentration of desired bottom product in the overhead stream. The output of the absorption unit is stabilized by alteration of the flow control apparatus associated with the output stream of the stripping zone in order to alter the amount of control over the output flow. A set point signal which controls the product output flow is generated in response to the predicted rate of delivery of product material to an accumulator and a modified signal related to the liquid level within the accumulator.

Improved fluid flow sensor configuration

Abstract: An improved fluid flow sensor configuration comprises a thin membrane of a low thermally conductive material having one surface in thermal contact with the heating and temperature sensitive elements of a fluid flow sensor and the other surface in thermal contact with a fluid whose flow rate is measured by the fluid flow sensor.

Flowmeter compensating system

Abstract: A fluid flow measuring system in which input pulses from a pulse-producing volumetric flow transducer and an analog signal representing the fluid temperature, pressure, density or other variable are processed to yield a corrected series of output pulses corresponding to net (processes corrected) mass or standard units of flow measurement. Correction for flow transducer calibration factor and resolution of the numerical output may be selectively adjusted. Both total flow and flow-rate over a range of fluid temperatures may be measured in net standard units of measurement.

Mass transfer between a horizontal, submerged gas jet and a liquid

Abstract: The rate of reaction between a horizontal, submerged gas jet and a liquid has been measured in a model system under conditions where mass transfer in the gas phase is rate limiting. The gas was 1 pct SO2 in air, and the liquid was a 0.3 pct solution of hydrogen peroxide in water. SO2 absorption rates were measured as a function of jet Reynolds number (10,000 < NRe < 40,000) and jet orifice diameter (0.238 < d0 < 0.476 cm). The product of the gas phase mass transfer coefficient and the interfacial area per unit length of jet trajectory, kSO2 α was found to increase linearly with increasing Reynolds number and to be a strong function of the orifice diameter. The ratio of kso2 α to volumetric gas flow rate was shown to be independent of Reynolds number for a given orifice diameter. Extrapolated values of kso2 α are lower than the coefficients measured for vertical CO jets blown upward through liquid copper. Extrapolation of the measured mass transfer data to the jet conditions in copper matte converting and in the gaseous deoxidation of copper has indicated that the gas utilization efficiencies in these processes should approach 100 pct if gas phase mass transport is rate controlling.

Flow Instabilities in a Capillary Rheometer for an Elastic Polymer Solution

Abstract: A modified capillary rheometer and a motion‐picture camera are used to simultaneously record the pressure at the inlet to the tube, the flow rate through the tube, and the flow patterns in the barrel prior to the entry to the tube. Measured flow curves, employing tubes in the range 14.7⩽L/D⩽36.7 for a medicinal grade liquid paraffin in the range 200⩽γ⩽4000 sec−1 and a highly elastic solution of Separan AP 30 in the range 100⩽γ⩽1500 sec−1, agreed well with the data obtained using a Haake Rotovisco cup and bob viscometer. Motion pictures of the flow patterns in the barrel for the Separan solution showed that the stable converging flow field at low flow rates developed a spiraling instability whose intensity increased with increasing flow rates until a complete breakdown of the flow field occurred at high flow rates prior to a second stage stability. Representative flow patterns in the range 40⩽4Q/ΠR3⩽5154 sec−1 are presented for L/D=36.7 which show the behavior over the entire spectrum of shear rates includ...

On the gas temperature in coaxial electric‐discharge CO2 flow lasers

Abstract: An analytic and experimental investigation on the dependence of gas temperature on flow and discharge characteristics is presented. The entire range of slow‐ to fast‐flowing coaxial CO2 electric lasers is considered. As is known, at low flow rates the gas temperature is proportional to the electric power input per unit length, while at high flow rates the gas end temperature is proportional to the ratio of total electric power and gas mass flow rate. In addition, gas pressure and entrance Mach number were found to have a noticeable effect on gas temperature; the temperature tends to increase with increasing pressure and to decrease with increasing Mach number. The agreement between theory and experiment is fairly good, so that estimates of gas temperature at given flow and discharge conditions can be obtained. Also presented is an experimental correlation between laser power output (or efficiency) and gas temperature. Finally, scaling laws for temperature‐limited coaxial flow CO2 electric lasers are proposed.

Comparison of direct and indicator-dilution measurements of flow rate and mean circulation time.

Abstract: An apparatus is described which enables the validity of bolus-injection indicator-dilution techniques to be investigated under a range of flow conditions. Volume flow rate, mean circulation time and vessel volume, calculated from experimentally determined dispersion curves by the standard indicator-dilution method, are compared with direct experimental measurements. As the flow rate is increased, discrepancies are found between the two sets of values. This is shown to be related to the manner in which the indicator is dispersed at the different flow rates. Agreement between the two methods is only obtained when diffusion dominates in determining the dispersion. A brief description of the conditions required for the indicator-dilution method to be suitable for physiological studies is given.

Cutting of a stream of tobacco into measured weight portions

Abstract: Method and apparatus for dispensing particulate material in portions of predetermined weight by providing a flow of material measurable by a radiation detector, measuring the flow rate per unit time of the material and removing successive determined portions of the material from the flow when the measurement indicates that each such portion is of predetermined desired weight.

Flow control valve

Abstract: A flow control valve for providing a selected rate of fluid flow to a controlled fluid operated device The valve includes a flow control member which is axially movable to select the flow rate of fluid to be supplied to the fluid operated device The flow control member is operable to establish a flow control orifice having an area linearly proportional to the axial position of the flow control member A pressure compensating device maintains a constant pressure drop across the orifice and thus the valve provides a controlled flow rate of fluid which is linearly proportional to the axial position of the control member

Discharge element for a liquid-gas separator unit

Abstract: A liquid-gas separator unit with superior performance characteristics is disclosed. The unit is characterized by a high liquid flow rate capacity at high as well as low accompanying gas flow rates, and efficient liquid-gas separation capability. The unit has a unique discharge plug element and a unique intake plug element that cooperate with a unique impeller means. Inlet/recirculation openings in the unit casing act to increase the liquid flow rate.

Analysis of moving fluids

Abstract: The invention concerns the analysis of moving fluids which may be slurries or the like. According to the invention the fluid to be analysed flows under pressure through an orifice at such a rate that it forms a clearly defined jet. Thus non-contact means such as an X-ray device can be used to analyse the fluid without the need of a window between the analysis means and the fluid. Means are provided both for determining the flow rate of the fluid in the jet and its dimensions so that the non-contact analysis means can be protected from damage should the flow rate or the dimensions of the jet vary beyond predetermined limits.

A gas flow system for esr measurements between 5 and 300 K

Abstract: Standard esr equipment for measurements at liquid helium temperature is used as a base for a gas flow system. The system operates at X and Q bands at temperatures down to 5 K. Temperature control is achieved by regulating the flow rate of the gas. It is stabilized to ±1 K. The helium flow rate required to maintain the lowest temperature is 0.12 liters/h.

Mixing two immiscible fluids of differing density

Abstract: Apparatus and method for first mixing continuously at a prechosen flow rate a less dense fluid with a more dense fluid, the fluids being at least partially immiscible, so as to achieve a constant weight ratio of one fluid to the other per prechosen unit of mixed fluid volume transversely across the path of such mixed fluid followed by charging the resulting mixed fluid simultaneously to a multiplicity of tubes in a tubular reactor under conditions of substantially plug flow. At least one of the fluid is a liquid at all times.

Apparatus for the simultaneous pumping-mixing of several non miscible liquids

Abstract: Improvement and greater efficiency in pumping-mixing of several non-miscible liquids and adequate flow rate control of liquids to be mixed are obtained through the use of centrifugal rotors and suction tubes which are independent for each liquid and connected to separate flow boxes. Efficient flow rate control of each liquid is obtained by regulating the inflow inlet section of each flow box and also by the extension of the screwable suction tube into the flow box and also by properly and adequately dimensioning the rotors.

Computation circuit for exhaust feedback flow - analogue control elements evaluate flow equation using negative and positive numbers

Abstract: An electronic calculating circuit enables the evaluation of the square roots of variables that are positive or negative to be evaluated in a feedback controlled exhaust gas emission control system. The exhaust gas feedback to reduce the carbon monoxide exhaust content is based upon the evaluation of a volumetric flow rate equation related to flow rate, pressure drop, upstream pressure, and temperature coefficient. Since pulsating flow occurs, a negative or positive pressure may be measured. The equation is evaluated by sensor outputs and an ambient temperature sensor output fed though analogue elements, such as an amplifier, multiplier, divider etc.