Abstract: Devices, methods, and systems for operating gas meters are described herein. The systems may include a gas meter connectable to a gas line, where the gas meter may have a metrology unit in communication with a flow of gas through the gas line and an index unit in communication with and releasably coupled to the metrology unit. The metrology unit may be configured to generate flow rate data of the flow through the gas line based on outputs from a flow rate sensor, generate gas temperature data based on outputs from a temperature sensor, compensate the flow rate data based on the temperature data, generate an average flow rate, and output the average flow rate data to the index unit. The index unit may generate gas volume data based on flow rate data received from the metrology unit.

Abstract: A method of monitoring an air flow in a zone (1) of an HVAC system (10) is described, the zone (1) comprising a supply port (11) and a return port (12), a first flow sensor (111) configured to measure a supply flow (?1) through the supply port (11), and a second flow sensor (121) configured to measure a return flow (?2) through the return port (12), the method comprising: recording by a control system (20, 20?) the supply flow (?1) measured by the first flow sensor (111) and the return flow (?2) measured by the second flow sensor (121); determining by the control system (20, 20?) an infiltration and exfiltration component (?inf/exf), using the supply flow (?1) and the return flow (?2) recorded by the control system (20, 20?); and determining by the control system (20, 20?) an operational sensor state of at least one of the first flow sensor (111) and the second flow sensor (121), using the supply flow (?1), the return flow (?2), and the infiltration and exfiltration component (?inf/exf).

Abstract: A distributor is described for distributing a fluid flow from a smaller to a more broad fluid flow. It comprises a fluid input and a plurality of fluid outputs, and a channel structure in between the fluid input and the plurality of fluid outputs. The channel structure comprises alternatingly bifurcating channel substructures and common channel substructures wherein the substructures are arranged so that fluid exiting different channels from a bifurcating channel substructure mixes in a subsequent common channel substructure, and whereby fluid channels of the bifurcating channel substructure are arranged such that these do not contact the subsequent common channel substructure at the edges thereof.

Abstract: The invention relates to a thermal type flow meter. The flow meter comprises a base part with at least two through bores extending substantially parallel to each other. A flow tube for the medium whose flow is to be determined is provided through the through bores. A part of the flow tube spaced from the base part comprises a measuring tube part where the flow of the medium can be measured. The flow measuring tube comprises an insulating housing connected to the base part, which surrounds at least the measuring tube part of the flow tube. The insulating housing comprises an inner housing surface, which faces the measuring tube part, as well as an outer housing surface, which faces away from the measuring tube part. According to the invention, a cover element connected to the base part is provided, which cover element at least substantially surrounds the insulating housing.

Abstract: A downhole viscosity sensor and related systems and methods are disclosed. The sensor includes a first fluid flow path including a turbine and a velocity sensor, a second fluid flow path including a second turbine and a second velocity sensor, a mechanical or electrical linkage linking the first turbine and second turbine to cause the turbines to rotate in unison. The sensor also includes a field generator, which may be a magnetic field or electric field generator. The first fluid flow path includes an open flow path for receiving a fluid from a formation and the second fluid flow path includes a closed flow path having a reference fluid that has a variable but known viscosity.

Abstract: An air conditioning service system includes an accumulator defining an accumulator chamber, a pressure transducer operably connected to the accumulator chamber, a drain valve operably connected to the accumulator chamber, and a controller operably connected to the pressure transducer and the drain valve. The controller includes a processor configured to execute program instructions stored in a memory to determine a volume of liquid drained from the accumulator by: determining a volumetric flow rate of liquid through the drain valve by controlling the drain valve with the controller to an open position for a predetermined period of time; detecting an increased rate of pressure reduction while the drain valve is open; and determining an amount of liquid drained through the drain valve based upon the volumetric flow rate and a total time elapsed between opening the drain valve and the increased rate of pressure reduction.

Abstract: Technical solutions are described for determining topological connectivity between stations of a fluid-delivery pipeline network. An example method includes receiving temporal sensor measurements of the fluid-delivery pipeline network, that include a series of sensor measurements from each respective station of the fluid-delivery pipeline network. The method also includes generating a causality graph of the fluid-delivery pipeline network based on the temporal sensor measurements, where the causality graph includes a set of nodes and a set of links, where the nodes are representative of the stations, and a pair of nodes is connected by a link in response to the pair of stations being temporally dependent. The method also includes determining a topological network of the stations based on the causality graph, where the topological network identifies one or more destination stations for a supply station in the fluid-delivery pipeline network.

Abstract: An insert apparatus for installing a transducer assembly in a sensor port of a flow cell is disclosed. The transducer assembly is installed in the cavity of the insert body without the use of glues or adhesives to bond the transducer assembly to the cavity.

Abstract: A process for producing biodiesel from natural oils and/or fats, a low molecular weight C1-C6 alcohol and catalyst is described. The process preferably uses vegetable oils and is specifically configured for producing biodiesel from castor oil.

Abstract: A fluid flow resistance modifying chemical additive system includes a flow loop, a first friction loop flow resistance measuring system coupled proximate an inlet side of the flow loop, at least one chemical additive device downstream of the first friction loop in the flow loop and a second friction loop flow resistance measuring system coupled proximate an outlet side of the flow loop. A method for continuous measuring effect of at least one flow resistance chemical additive on a base fluid include pumping the base fluid into a flow loop. A property of the base fluid is measured. At least one modifying chemical is added to the base fluid. The property of the combined base fluid and at least one flow resistance modifying chemical is then measured and/or modified with respect to the flow resistance properties of the base fluid.

Abstract: A system for measuring flow rate with at least a first and a second flow meter provides a flow-rate measurement system which easily allows self-monitoring. This result is achieved by the system in that the first flow meter and the second flow meter differ from one another and/or have different orientations for the flow rate measurement, and each have an evaluation unit which produces data from the flow rate measurement. Furthermore, there is a monitoring device which is connected to the evaluation units such that the monitoring device acquires data produced by the evaluation units, and which is made such that it produces at least one comparison result from a comparison of the data produced by the evaluation units and signals at least the occurrence of a fault state which is associated with at least one comparison result.

Abstract: The present invention provides a fluid distribution device for uniformly distributing and outputting a fluid, which is supplied to an input flow channel, into at least three output flow channels, comprising a plurality of branch flow channels, at least three fluid bifurcation portions, and at least one fluid converging portion, wherein the fluid distribution device is configured to correspond to a pressure drop compartment connection model composed of a fluid balance equation and a pressure balance equation. Furthermore, the present invention provides a micro plant using the fluid distribution device, a method of designing the fluid distribution device and a method of detecting blockage of flow channels of the fluid distribution device.

Abstract: A material characterization system and method for quantifying the characteristics of a flowing thermoplastic material is presented. The system comprises a tool comprising first and second tool halves, a plurality of flowing material characterization channels, and a feed runner. The tool is at a temperature that causes phase changes from fluid to solid in at least a portion of the characterized material and enables solidification of the material in the flowing material characterization channels. The feed runner is connectable to a single flowing material characterization channel. The tool is adjustable to disconnect the feed runner from one flowing material characterization channel and connect it to different flowing material characterization channels. A sensor quantifies the characteristics of the material under different flow conditions.

Abstract: An exemplary method and apparatus for function testing of plastic containers which have been produced in an extrusion blow molding method and include an ascending tube. The apparatus being configured to determine the flow rate of a fluid medium through the ascending tube. The determined flow rate is compared to a set flow rate range, and when upper and lower boundaries for the flow rate are not reached or are exceeded, the container is excluded from further processing and removed from the process.

Abstract: A method, a fire alarm, and a fire alarm system enable detection and localization of a fire in monitored rooms, having two detector units for detecting a fire parameter, wherein an evaluation unit connected to both detector units is used for evaluation. According to the invention, the air in the monitored rooms is fed to the first detector unit via a first pipe conduit and to the second detector unit via a second pipe conduit. Both pipe conduits are arranged in each monitored room and provided with suction intakes. The air is supplied to both detectors by means of at least one suction unit, and the air speed in each pipe conduit is different.

Abstract: In order to discriminate between laminar flow and turbulent flow states, and to provide an indication, e.g. to a pilot of an aircraft of air flow over an aircraft wing, a sensor mounted on the wing provides an analogue signal of airflow, and an intermittency value of the analogue signal is derived in analogue circuitry including an AC coupling of the signal to an integrator for integrating the signal for a preset time. The integrated value is compared with a threshold value to indicate whether the intermittency represents quiet laminar flow or noisy turbulent flow.

Abstract: The present invention relates to a method for determining at least a first volume flow in a blood treatment apparatus which comprises: a primary circuit for conducting the blood to be treated; a secondary circuit for conducting a fluid that is used for the blood treatment; a blood treatment module provided for exchanging fluids and/or substances between the primary circuit and the secondary circuit; and an optionally provided fluid connection between the primary circuit and the secondary circuit, provided for introducing the first volume flow from the secondary circuit into the primary circuit; wherein the method encompasses determining the first volume flow of the secondary circuit taking into account a first pressure value or pressure measurement and a second pressure value or pressure measurement in the secondary circuit. The present invention further relates to a calculating device and a blood treatment apparatus.

Abstract: A fluid measurement apparatus capable of accurately determining an activated appliance is provided. A flow measurement apparatus 100 has a flow measurement unit 12 that measures an amount of fluid flowing through a passageway, a determination zone storage unit 16 that allocates and stores a flow measured by the flow measurement unit 12 into determination zones classified by combination of a plurality of conditions; a grouping unit 18 that groups determination zones according to appliances to be used on the basis of determination-zone-specific storage values stored in the determination zone storage unit 16 and that registers the grouped determination zones; and an integration unit 20 that integrates a flow value for each of the determination zones registered by the grouping unit 18. Thus, a flow is integrated for each determination zone grouped according to an appliance. An appliance is determined by reference to a database including the integrated data.

Abstract: Exemplary illustrations of a rotary atomizer and methods of using the same are disclosed. An exemplary illustration is directed to the function control of a rotary atomizer used for the serial coating of work pieces. This is achieved in that pressure values, which result within or outside of the directing air flow of the atomizer, may be measured and compared to predefined reference values for error-free atomizer functions.

Abstract: A substrate processing apparatus and a method of confirming operation of a liquid flowrate control device. The apparatus includes a process chamber accommodating a substrate, a liquid source supply system supplying a liquid source into the chamber at a liquid state at room temperature and under atmospheric pressure, a solvent supply system supplying a solvent into the chamber having a vapor pressure greater than the liquid source, a liquid flowrate control device controlling flowrates of the liquid and solvent, and a controller controlling the liquid and solvent supply systems, and the liquid flowrate control device. The controller controls the liquid and solvent supply systems, and the liquid flowrate control device so the solvent is supplied to the liquid flowrate control device to check an operation of the liquid flowrate control device before the liquid source supply system supplies the liquid into the chamber via the liquid flowrate control device.

Abstract: A method and apparatus for determining a level of stratification of a multiphase fluid flow passing through a pipe is provided. The method includes, and the apparatus is operable to perform, the steps of: 1) determining a flow velocity of the multiphase fluid flow passing through a first radial region of the pipe; 2) determining a flow velocity of a portion of the multiphase fluid flow passing within a second radial region of the pipe, wherein the second radial region is above the first radial region; and 3) comparing the flow velocity from the first radial region and flow velocity from the second radial region to determine information indicative of the stratification of the multiphase fluid flow.

Abstract: The application is directed to methods, systems, procedures, networks and storage apparatus used to conduct conversions of data using remote conversion servers. In one embodiment of the present invention, recent query results may be stored and then used to solve subsequent conversions rather than querying a remote conversion server when the same conversion was previously completed. A counter may be referenced to determine if too much time has passed since the original query was stored in the buffer and, if too much time has passed, the buffer may be cleared and the remote conversion server may be queried to convert the pending data. The resulting conversion may be stored for subsequent use.

Abstract: One embodiment provides a flow meter including an airfoil movably secured in the airflow path of a fan in an electronic system. The airfoil is configured to generate a lift component in response to the airflow. A sensor engages the airfoil and generates a signal in relation to the movement of the airfoil. Airflow parameters such as volumetric airflow rate and turbulence may be identified by an analysis of the movement of the airfoil.

Abstract: A substrate processing apparatus, a method of manufacturing a semiconductor device, and a method of confirming an operation of a liquid flowrate control device are provided. The substrate processing apparatus comprises: a process chamber accommodating a substrate; a liquid source supply system supplying a liquid source into the process chamber; a solvent supply system supplying a solvent having a vapor pressure greater than that of the liquid source into the process chamber; a liquid flowrate control device controlling flowrates of the liquid source and the solvent; and a controller controlling the liquid source supply system, the solvent supply system, and the liquid flowrate control device so that the solvent is supplied into the liquid flowrate control device than the solvent supply system to confirm an operation of the liquid flowrate control device before the liquid source supply system supplies the liquid source into the process chamber.

Abstract: The present invention provides a fluid distribution device for uniformly distributing and outputting a fluid, which is supplied to an input flow channel, into at least three output flow channels, comprising a plurality of branch flow channels, at least three fluid bifurcation portions, and at least one fluid converging portion, wherein the fluid distribution device is configured to correspond to a pressure drop compartment connection model composed of a fluid balance equation and a pressure balance equation. Furthermore, the present invention provides a micro plant using the fluid distribution device, a method of designing the fluid distribution device and a method of detecting blockage of flow channels of the fluid distribution device.

Abstract: A method for determining the balance between an amount of supplied cooled air and an amount of discharged heated air in a temperature- and air humidity-conditioned space in which ICT equipment is disposed which gives off heat to passing cooled air so that this air is heated up, wherein the free movement of a reference stream of air in the space is monitored by measuring a signal which is imparted to the air of the reference stream with the aid of a signal source. The invention further relates to an apparatus for determining the balance between an amount of supplied cooled air and an amount of discharged heated air in a temperature- and air humidity-conditioned space in which ICT equipment is disposed which gives off heat to passing cooled air so that this air is heated up, comprising a measuring tube for monitoring the movement of a reference stream of air.

Abstract: A gas meter with a simple structure for detecting a range from a minute flow rate, such as a gas leak, to the large flow rate of the normal state of use of the gas, while protecting the flow rate sensor from dust and without producing the problem of pressure loss. First, second, and third flow paths for carrying partial flows of a gas to be measured, in accordance with the flow rate, are provided by partitioning, in parallel, the cross-sectional surface of a main flow path. A flow rate sensor for flow rate measurement is provided in the first flow path with a small flow path cross-sectional area, and a flow rate sensor for detecting a gas leak is provided in the second flow path with a small flow path cross-sectional area, where a flow baffling filter is provided on one end side or both ends of the first and second flow paths, and a contaminant (dust) removing filter is provided on one end side or both ends of the first flow path.

Abstract: Multi-phase flow is estimated in a flow meter having a first and a second stage by empirically deriving an algorithm for the water and gas fractions, measuring pressures within the flow meter, and estimating a total mass flow rate based on the measured pressures. A corrected total mass flow rate is calculated using a liquid/gas slip correction technique. The oil fraction can be determined from the corrected total mass flow rate and gas and water fractions.

Abstract: A water meter has a meter register having an encoder having electromagnetic wave emitters, e.g., infrared emitters to measure water flow and direction of water flow through the meter. The encoder has two of three spaced emitters directing infrared rays at predetermined time intervals toward a rotating detector wheel having a reflective surface portion and a non-reflective surface portion facing the emitters and an infrared sensor. The reflective surface portion of the detecting wheel reflects the infrared rays incident thereon toward the sensor. A microprocessor connected to the sensor acts on signals from the sensor to determine material flow. The meter register transmits the signal to a distant receiver. The microprocessor of a meter register has an algorithm to prevent the meter register from sending signals until after the meter register or a water meter having a meter register is installed and water moved through the meter.

Abstract: The pressure at a pressure sensor is cycled between a higher (upstream) pressure and a lower (downstream) pressure. The pressure sensor senses the higher and lower pressures, and the difference therebetween is calculated and output. The pressure sensor can be a “single-pressure” pressure sensor (gage or absolute) where the pressure sensor is alternately connected between the two pressures.

Abstract: A system and method for determining functionality and accuracy of a sensor such that monitoring of a sensor is possible without the provision of redundant sensors. Briefly described, one embodiment is an anemometer operable to detect wind speed adjacent to the wind power installation, a calculating unit operable to calculate a calculated wind speed using data from an operating parameter of the wind power installation, and a comparison device operable to compare the detected wind speed with the calculated wind speed to determine the functionality of the anemometer.

Abstract: An arrangement for measuring air flow includes a source of measurement values and a processing unit. The source of measurement values is operable to generate measurement values representative of a difference in pressure from air obtained on a first side of an obstruction and air obtained on a second side of the obstruction. The processing unit is configured to, in one case, convert any negative measurement values of the measurement values to a less negative value. The processing unit is further configured to perform low pass filtering on the measurement values and convert the filtered measurement values to a flow value.

Abstract: When a discharge trouble such as clogging has occurred in a plurality of branch tubes branched from a flow tube coupled with a pressure vessel, it is displayed immediately as a flow rate variation in the flow tube. A Judgment section of a dispensing system, therefore, finds the discharge trouble in the branch tubes immediately based on a flow rate detected by a flow-rate detector provided on the flow tube. Moreover, the judgment section identifies the branch tubes where the discharge trouble has occurred based on the respective flow rates of the branch tubes opened individually or opened in a predetermined combination.

Abstract: A method for ice detection for a wind turbine is provided. The method includes providing an ice condition threshold parameter adapted for distinguishing a condition during which icing may occur and a condition during which icing may not occur, measuring a wind velocity with a first anemometer, wherein the first anemometer being of a first type, measuring a wind velocity with a second anemometer, wherein the second anemometer being of a second type, and wherein the second type is different from the first type, evaluating, for a condition during which icing may occur, a deviation of the wind velocity measured with the first anemometer and the wind velocity measured with the second anemometer, and determine whether the deviation exceeds a limit value based on a calibration conducted under a condition during which icing may not occur.

Abstract: A metering assembly includes a fluidic chip and metering chambers. Selectable outlet valves communicate with each metering chamber to provide a discrete dispensed volume. The valves may be commonly controlled and may be formed as multi-level valves. The valves may be grouped into common substrate valve clusters. Purge channels communicate with the metering chambers and controlled purge valves allow reverse flow wash fluid to wash the metering chamber. Pressure ports are employed to actuate the valves. A method of dispensing a fluid from the fluidic chip includes a) selectively filling (or filling) the metering chambers with a selected fluid; and b) outputting (or selectively outputting) the fluid to output locations. The total output volume of fluid dispensed from each metering chamber may be accumulated. The process may be repeated until the accumulated volume equals the desired volume and may be repeated for another fluid from a plurality of different fluids.

Abstract: The present invention provides for a lightweight metal framing member having a plurality of depressions and a plurality of reinforcing ribs on the surface thereof, the depressions and ribs both being inwardly oriented and cooperating to aid in stiffening of the metal stud. The present invention also provides a method of manufacturing a metal framing member having a plurality of depressions and a plurality of reinforcing ribs on the surface thereof, the depressions and ribs both being inwardly oriented and cooperating to aid in stiffening of the metal stud. The method utilizes a cold roll forming apparatus having a first roller with a plurality of projections on its surface and a second roller having a surface provided with holes aligned with the projections on the surface of the first roller to form the depressions in the surface of the material having clearly defined edges generally aligned with the plane of the metal sheet.

Abstract: A method for performing system characterization in situ for a system comprising a actuator controlled by a proportional controller. The system includes a quasi-linear region characterized by a slope of the system response and by a delay in the quasi-linear region of the system. The system includes at least one dead zone (DZ).

Abstract: The present invention concerns a method of monitoring a sensor for sensing the flow speed of a medium. The invention further concerns an apparatus for carrying out that method. In order to be able to monitor the sensor, without providing redundant sensors, the flow speed of the medium, which is specified by the sensor, is correlated with at least one operating parameter of an installation operated with the medium. For that purpose the apparatus according to the invention includes a sensor for detecting the flow speed of a medium, an installation operated with the medium and a correlation device for correlating the flow speed of the medium, which is specified by the sensor, with at least one operating parameter of the installation.

Abstract: A device for measuring the volume flow or other substance properties of a gas, whose direction of flow can reverse. The arrangement contains a specially designed Y-piece, which is used for branching into direction-dependent flow paths and can be used at the same time for the measurement. Such devices can be preferably used in the area of mechanical respiration.

Abstract: Method and apparatus are provided to exchange fluid in a system such as a transmission system. Supply and return flow rates are measured and can be adjusted based on a difference between the flow rates.

Abstract: A fluid flow system for continuously monitoring the flow of fluid including fluid flow conduit with an upstream side and a downstream side, sensors and fluid flow elements, with the method for analyzing the operation of a fluid flow system by determining whether the fluid flow subsystem of the main system is operating properly, inputting a sensor reading of the parameter in the fluid flow of the main system and outputting an error indication of the main system.

Abstract: A method and apparatus for in-situ calibration of quantity measurement of a fluid flowing in a channel, in which a device for measuring the volume of the fluid is disconnected from the fluid flow, measuring fluid is accumulated in a pre-determined amount on site of the calibration, this pre-determined amount of measuring fluid is led through the measuring device with a pre-determined volume flow, in the course of which the volume values measured by the measuring device are saved, then the measured volume values and the real values of the fluid led through are compared to each other and, with this, the quantity measurement of the flowing fluid is calibrated.

Abstract: Method and apparatus are provided to exchange fluid in a system such as a transmission system. Supply and return flow rates are measured and can be adjusted based on a difference between the flow rates.

Abstract: In a system and a method for purging a vapor storage canister having adsorbed fuel vapor (or hydrocarbon vapor) by drawing air through the storage canister the storage canister being coupled with an engine having a system for controlling the amount of fuel provided to the engine, the amount of fuel vapor in the purge is determined by subtracting from a known total flow rate of air and vapor from the canister a measured air flow rate of air into the canister. The total flow rate of air and vapor from the canister may be obtained, for example, by knowing the intake manifold vacuum, by using a pump at a given flow rate capacity to draw the air and vapor through the canister, or by using a valve having a given flow rate that limits the flow rate of the air and vapor mixture drawn from the canister. An ECM or PCM can use the information of fuel vapor flow from the canister obtained in this way for better fuel control.

Abstract: In an automated welding machine, where a flow of liquid coolant is supplied to welding components on the machine from a source of coolant and then returned to the source of coolant, a safety system is provided that shuts down the flow of coolant in the event of a fault. Faults are detected by a supply sensor and a return sensor for measuring the flow rates of coolant in the supply and return lines. A microprocessor is adapted to compare the supply flow rate and return flow rate and detect differences between the two rates. The difference between the detected rates as compared to a leak threshold value, and the microprocessor is adapted to generate a valve shutoff signal in the event the detected difference in flow rates exceeds the leak threshold value. A value in the supply coolant line is responsive to the valve shutoff signal to shutoff flow of coolant in response thereto.

Abstract: A method and apparatus for determining a state of zero gas flow in a conduit, the zero flow state occurring between a first period in which gas flows in one direction in the conduit and a subsequent, second period in which gas flows in the opposite direction in the conduit. A first signal responsive to gas flow in the conduit is obtained. The first signal has one polarity when the gas flow is in one direction in the conduit and the opposite polarity when the gas flow is in the opposite direction. A second signal responsive to the gas flow in the conduit is also obtained. The second signal has the same polarity for either direction of gas flow in the conduit. The derivatives of the first and second signals are taken at successive points in time to determine when the signs of the derivatives of the first and second signals are present in a first predetermined combination of signs.

Abstract: A system for monitoring a water consuming structure in an individual unit of a multi-unit building, comprising means for determining that volumetric flow through the pipe proximate the water consuming structure has been continuous during a predetermined period of time, the predetermined time being selected to be greater than a period of time during which water should be flowing continuously through the pipe, and means for transmitting an alarm signal in the event that it is determined that flow to the water consuming structure has been continuous for the predetermined time.

Abstract: In an automated welding machine, where a flow of liquid coolant is supplied to welding components on the machine from a source of coolant and then returned to the source of coolant, a safety system is provided that shuts down the flow of coolant in the event of a fault. Faults are detected by a supply sensor and a return sensor for measuring the flow rates of coolant in the supply and return lines. A microprocessor is adapted to compare the supply flow rate and return flow rate and detect differences between the two rates. The difference between the detected rates as compared to a leak threshold value, and the microprocessor is adapted to generate a valve shutoff signal in the event the detected difference in flow rates exceeds the leak threshold value. A value in the supply coolant line is responsive to the valve shutoff signal to shutoff flow of coolant in response thereto.

Abstract: The method of measuring the mixing efficiency in porous tubes comprising generating gas waves the composition of which at substantially constant total flow rate and pressure varies sinusoidal with time, causing said gas waves to flow through a section of said tubing from inlet to outlet, periodically sampling the gas waves in said tubing at a first point at the peak amplitude of the concentration of a first gas, sampling said waves at a second point at the peak amplitude of the concentration of a first gas, measuring the concentration of said first gas in said mixture in both said samples, and deriving and recording the difference in said concentration for each sampled wave, the difference of said concentrations at said peak amplitudes being a measure of the mixing efficiencies of said tube.

Abstract: A method of predicting logarithmic reduction values for a membrane filtration system having a filtrate flow portion and a bypass flow portion relative to a filtrate permeable membrane with stable input gas flow comprising: determining the filtrate flow rate through the membrane under the action of an applied test pressure, determining the membrane bypass flow rate using integrity test measurements and estimating the logarithmic reduction value using the ratio of determined filtrate flow rate and determined bypass flow rate. Methods of testing the integrity of a porous membrane are also disclosed.