Abstract: Recovery of dehydrogenation product must be done separately from supply of hydrogen fuel. However, there is a problem that it takes much time when dehydrogenation product recovery and fuel filling are done separately. A fuel filling/waste solution recovery apparatus includes measuring means to measure a volume of supplied fuel and a volume of recovered waste solution by measuring flow rates of solutions passing through a fuel filling nozzle and a recovery nozzle or piping, and a display which shows the volume of supplied fuel and the volume of recovered waste solution which are measured by the measuring means.

Abstract: A system and method for measuring aeration of a liquid in a liquid channel operates by sending an ultrasonic wave into a liquid channel, receiving a signal corresponding to the echo from the liquid channel and calculating a level of aeration of the liquid in the liquid channel based on the reflected signal.

Abstract: The invention is directed towards methods and apparatus for accurately detecting the presence and concentration of an oxidant in a turbid water sample. This method is very helpful in allowing accurate and efficient (not too much nor too little) amounts of microbe killing oxidants to be introduced to water supplies that require oxidants but which at present cannot be measured properly. The method comprises the steps of: passing the water through at least one filter array, passing the filtered water to an analyzer, and then returning from the analyzer a measurement of the concentration. The filter array comprises at least one filter constructed and. arranged to remove turbidity inducing material but not oxidant from the water sample. The analyzer can be a commonly commercially available analyzer that currently cannot accurately measure the oxidant concentration if the water had not been so filtered.

Abstract: A system for measuring the permeance of a material. The permeability of the material may also be derived. The system provides a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.

Abstract: The inventive method is designed to test contaminants in soil that is contaminated with petroleum related products. The method involves the use of a container that will separate soil into a head space for analysis. The container consists of two halves and the container is partially filled with a soiled dirt specimen. The container is then hermetically sealed against the environment by way of a cover snapped over the container rim. The container with the contaminated specimen therein is allowed to accumulate a vapor head space within a certain time period. An instrument will puncture a sealed orifice in the top cover and a sample of the vapor is withdrawn for further analysis.

Abstract: A stack of substantially parallel ceramic plates (22) separated and interconnected by ceramic spacers (26, 27) forming a seal structure (20) with a length (L), a width (W), and a thickness (T). The spacers are narrower in width than the plates, and may be laterally offset from spacers in adjacent rows to form a space (28) in a row that aligns with a spacer in another adjacent row. An adjacent plate bends into the space when the seal structure is compressed in thickness. The spacers may have gaps (60, 62) forming a stepped or labyrinthine cooling flow path (66) within the seal structure. The spacers of each row may vary in lateral separation, thus providing a range of compressibility that varies along the width of the seal structure.

Abstract: A method of measuring a property of entrained gas in a hydraulic liquid received by a working chamber of a fluid working motor, wherein the said property is determined from the period of time elapsing between the closure of a first valve to isolate the working chamber and the passive opening of a second valve to bring the working chamber into fluid communication with a manifold. The property may, for example, be related to the concentration of entrained gas in the received hydraulic liquid or the compressibility or bulk modulus of the received hydraulic fluid.

Abstract: Disclosed herein is a method and apparatus for analyzing, sensing and measuring information related to the concentrations of various gases, including NOx, hydrocarbons, carbon monoxide and oxygen, in a multi-component gas system using chemical sensors and chemical sensor arrays. The sensors and sensor arrays use chemo/electro-active materials to analyze and detect the presence of gases.

Abstract: The inventive method is designed to test contaminants in soil that is contaminated with petroleum related products. The method involves the use of a container that will separate soil into a head space for analysis. The container consists of two halves and the container is partially filled with a soiled dirt specimen. The container is then hermetically sealed against the environment by way of a cover snapped over the container rim. The container with the contaminated specimen therein is allowed to accumulate a vapor head space within a certain time period. An instrument will puncture a sealed orifice in the top cover and a sample of the vapor is withdrawn for further analysis.

Abstract: Method for controlling the process of separating mixtures containing several substances having close boiling points and with a known concentration, in a distillation column, wherein the concentration of at least one component is measured at a midpoint of the column, and said measurement, together with other parameters, is used to control the process.

Abstract: The invention relates to a method of controlling a hydrogenation of a starting material in a hydrogenation reactor, in which the amount of hydrogen reacted in the hydrogenation is firstly determined, the ratio of the amount of hydrogen reacted to the amount of starting material fed in is then derived, this ratio is compared with a prescribed value and, finally, at least one process parameter is altered if the ratio of the amount of hydrogen reacted to the amount of starting material fed in deviates by a prescribed amount from the prescribed value.

Abstract: A medical fluid air detection apparatus includes an emitter, a receiver, a housing configured to hold at least a portion of a medical fluid conduit between the emitter and the receiver, where the medical fluid conduit includes a narrowed inner diameter at the medical fluid conduit portion that forces flow of medical fluid through the narrowed diameter, and where the narrowed diameter is configured to enhance operation of the emitter and the receiver.

Abstract: The present invention relates to an adsorbed gas content measuring instrument and its testing method. The instrument comprises sealed cylinders, gas collecting graduated canisters and a test box, wherein the sealed cylinders are provided with valves, the gas collecting graduated canisters are equipped with drain hole adjustment valves and vent hole switching valves fit for the valve ports, and there is a heating element and a temperature controller in the test box. The method is mainly as follows: put gas-contained samples and saturated brine into the sealed cylinder, seal the cylinder, feed water in the test box and heat the box, place the sealed cylinder into the water bath of the test box, introduce saturated brine into the gas collecting graduated canister, connect the canister and cylinder, open the drain hole of the gas collecting graduated canister, record the liquid level of the graduated canister and cut off the connection after the test.

Abstract: System for detecting and removing gas bubbles from a vascular infusion line, including a cassette adapted for disposition intermediate the fluid line, the cassette including a flexible tube having an inlet port for connection to a supply side of the fluid line, an outlet port configured for connection to a patient side of the fluid line, and a purge port intermediate the inlet and outlet ports, and a base unit adapted to receive the cassette and monitor fluid flow through the tube, the base unit including a sensor to detect the presence of a gas bubble in the fluid flow, a pinch valve adapted to stop the flow of fluid, and a control unit adapted to operate the base unit so that (i) fluid is permitted to flow past the pinch valve when no gas bubble is detected; and (ii) fluid flow is arrested when a gas bubble is detected.

Abstract: An IMS system or the like has dopant contained in a way such that it is only released when needed. The dopant could be contained in a device (50) similar to an ink-jet printer and released as droplets (55) when required. Alternatively, the dopant could be trapped in material (156) of a molecular sieve (150) in such a way that it is not normally released into air flowing through the sieve but can be released by energising a heater (157) in the sieve.

Abstract: One embodiment of the invention includes a method comprising measuring the level of a fluid in a system in a vehicle comprising measuring an electrical property of the fluid indicative of the amount of air in the fluid and comparing the measured electrical property to a reference. The measured electrical property may include at least one of electrical resistivity or electrical permittivity. Another embodiment of the invention includes a method comprising measuring an electrical property of a fluid, measuring an electrical property of an air-free fluid sample, and determining a volume fraction of air in the fluid using the electrical property of the fluid and the electrical property of the air-free fluid sample, wherein the electrical property comprises at least one of electrical resistivity or electrical permittivity. In some embodiments an indication can be provided when the slope of the electrical property versus time changes.

Abstract: A universal air bubble detector allows for use with a variety of sizes and types of tubing. The detector maintains proper alignment of a sensor emitter and receiver with different sizes of tubing. The detector may be mounted on existing equipment or may be used to monitor a tubing at any position along the tubing, and may operate in a stand alone mode or in combination with existing equipment.

Abstract: An apparatus for detecting a volatile dissolved substance includes a sample vessel 1 capable of holding therein an approximately fixed amount of liquid A, B with leaving a space at an upper inner section thereof; a nozzle 4 capable of blowing off bubbles into the liquid held in the sample vessel, and a pressurized gas feeding device L capable of feeding pressurized gas to the nozzle for the blowing of the bubbles. Within a communication passage 5 communicating with the upper section of the sample vessel, there is exposed a detecting portion of a sensor S capable of detecting a volatile component, so that the sensor can detect the volatile component which has evaporated from the liquid in the sample vessel and entered the communication passage.

Abstract: In order to determine the gas hydrate anti-agglomeration power of a system composed of an aqueous phase dispersed in a liquid hydrocarbon phase in the presence of a gas, at least two successive cycles of hydrate formation and dissociation is carried out by cooling and reheating a sample of said system placed in the cell of a calorimeter to record thermograms; the anti-agglomeration power of said system is determined by comparing the thermograms obtained during the various cycles.

Abstract: A nanocrystalline ITO thin film formed on a quartz crystal microbalance (QCM) facilitates detection of gaseous compounds emitted from an analyte. Adsorption of gas molecules onto the nanocrystalline ITO thin film changes the resonant frequency of the quartz crystal. Parameters such as the frequency of oscillation, surface resistance, integrated frequency response, integrated surface resistance response, initial response slope, average return to baseline slope, and/or return to baseline time/initial response time ratio of the quartz crystal with the nanocrystalline ITO thin film formed thereon are determined. Using the determined parameters and principal component analysis, principal components for the gaseous compounds are also determined. These determined principal components may be compared with known principal components corresponding to known analytes.

Abstract: The inventive device (53) comprises an enclosure (63), means (65) for supplying the drilling mud into the enclosure (63), and means (67) for discharging the drilling mud from the enclosure (63). The device also comprises means (69) for introducing a carrier gas into the enclosure (63) and a pipe (71), which serves to extract the gas discharging into the enclosure (63) and which is connected to suction means (109). The device (53) additionally comprises selective venting means (72) comprising a vent pipe (115) perforated over the extracting pipe (71) and means (117) for closing the vent pipe (115). These means (117) are designed for opening the vent pipe (115) when the pressure at at least one point (121) of the device is less than a predetermined set value. The invention is used for analyzing the gaseous content of muds from drilling oil wells.

Abstract: A system for measuring parameters in a container is disclosed. A system for measuring multiple parameters includes a container having a solution, at least one sensor in conjunction with a tag is in proximity to an impedance analyzer and a reader that constitute a measurement device. The at least one sensor is configured to determine at least one parameter of the solution. The tag is configured to provide a digital ID associated with the sensor, where the container is in proximity to the reader and an impedance analyzer. The impedance analyzer is configured to send and receive a given range of frequencies from the sensor, based on the parameter and calculate parameter changes based on the response.

Abstract: A method to efficiently measure the oxygen content of both the headspace and fluid within a hermetically sealed container. A container is pierced using a hollow needle with the interior space sealed from the outside and the tip of said hollow needle removed, and the interior space is made continuous with the headspace within the container. A probe of a fluorescent oxygen concentration meter is inserted through the hollow needle to the interior of the container, positioned in the headspace within the container, and the oxygen concentration of the headspace 3 is measured. The probe is inserted further so that the fluorescent material is submerged in the fluid inside the container, and the dissolved oxygen concentration inside the fluid is measured.

Abstract: The present invention relates to a dialysis liquid circuit with conduits for conducting dialysis liquid and with means for detecting air in the dialysis liquid, wherein the means comprise at least one gas sensor traversed continuously by the dialysis liquid, which is configured such that it measures at least one property of the dialysis liquid which depends on the presence of air bubbles in the dialysis liquid, and which is arranged downstream of a region to be monitored of the dialysis liquid circuit, in which during operation of the dialysis liquid circuit a negative pressure exists with respect to atmospheric pressure, wherein the means comprise an evaluation unit which is connected with the gas sensor and which is configured such that the property measured by means of the gas sensor is evaluated with regard to the presence of air bubbles in the dialysis liquid.

Abstract: In the hydrogen remaining sensor of the present invention, the hydrogen remaining sensor is arranged in a space in which the hydrogen is absorbed/released by the main hydrogen storage alloy, and is equipped with the vessel-like sensor main body in which the sensor hydrogen storage alloy is filled and through which the hydrogen is moved. Also, the easy-to-deform portion in which the strain is caused easily due to the hydrogen absorption/release of the sensor hydrogen storage alloy is provided to a part of the sensor main body, and the strain gauge for measuring the strain of the easy-to-deform portion is provided. As a result, according to the hydrogen remaining sensor of the present invention can contribute to sense precisely a remaining amount of hydrogen in the main hydrogen storage alloy.

Abstract: There is provided a method for detecting a target material, preferably a solid or liquid target material. The method may comprise the steps of targeting a material for analysis, heating the material with a heating source from a remote distance to effectively increase a temperature of the material and to effectively increase a vapor pressure of the material in an environment adjacent to the material, measuring with a sensor the material vapor in the adjacent environment from the remote distance, and detecting the identity of the material using data generated during the measuring step. There is also provided a system for detecting a target material having a low vapor pressure comprising a first energy generating source, a sensor for measuring properties of gaseous materials from a standoff distance, the sensor producing data, and a computer for determining the target material based on the data produced by the sensor.

Abstract: A canister for measuring the natural gas content of rock cores which (1) has an inner core-containment bag made of non-permeable plastic which can be flash evacuated, collapsing around the core and thus minimizing the amount of air present and improving the quality of the gas analyses and (2) which prevents the released gas from reacting with the outer canister. A procedure for using gas-sampling bags to periodically collect the gas released from the core so that (1) the volume of released gas can be measured at a later date using more convenient and precise laboratory methods, (2) the gas can be readily transported and stored, and (3) the gas can be easily submitted for analysis.

Abstract: A gas flux chamber assembly is provided that includes a lift-and-rotate mechanism and a chamber. The chamber is moved between first and second positions, wherein the chamber is positioned over a sample in the first position and is positioned outside of an area above the sample in the second position. In operation, the chamber is first lifted off of the collar and is then rotated, about a rotational axis outside of the area above the collar. These acts are reversed to move the chamber from the second position to the first position.

Abstract: A monitor for monitoring gas concentration in an aerospace application is described, one such application being measuring the concentration of oxygen in or next to aviation fuel. The monitor comprises: a substance, the spectroscopic properties of which change when the substance is exposed to the gas; a light source, arranged to irradiate the substance with light; and a photosensor, arranged to detect light from the substance. The substance may be mounted on a solid substrate.

Abstract: Various methods are described for measuring parameters of a stratified flow using at least one spatial array of sensors disposed at different axial locations along the pipe. Each of the sensors provides a signal indicative of unsteady pressure created by coherent structures convecting with the flow. In one aspect, a signal processor determines, from the signals, convection velocities of coherent structures having different length scales. The signal processor then compares the convection velocities to determine a level of stratification of the flow. The level of stratification may be used as part of a calibration procedure to determine the volumetric flow rate of the flow. In another aspect, the level of stratification of the flow is determined by comparing locally measured velocities at the top and bottom of the pipe. The ratio of the velocities near the top and bottom of the pipe correlates to the level of stratification of the flow. Additional sensor arrays may provide a velocity profile for the flow.

Abstract: A gas flux chamber assembly with a soil collar and a chamber is provided. The chamber is moved between first and second positions, wherein the chamber is positioned on the soil collar in the first position and is positioned outside of an area above the soil collar in the second position. In operation, the chamber is first lifted off of the soil collar and is then rotated, about a rotational axis substantially parallel to the soil collar axis, outside of the area above the soil collar. These acts are reversed to move the chamber from the second position to the first position.

Abstract: A method and pump that accurately senses air in a fluid delivery line pulses or activates and deactivates the air sensor(s) multiple times during the pumping phase of the fluid delivery cycle and can generate alarms based upon a single indication or a cumulative indication of air in the line. The pump can include multiple air sensors spaced along the delivery line so that the method can use the multiple signals therefrom to distinguish real moving air bubbles from false positives and/or air bubbles adhered to the inner wall of the line.

Abstract: A system for determining gas content in an enclosed atmosphere (6) is provided. The system for determining gas content includes a window unit (2, 4) having an enclosed atmosphere and an oxygen sensing material (8) disposed in the enclosed atmosphere. The oxygen sensing material detects a level of oxygen in the enclosed atmosphere. A non-invasive sensor (10) reads the oxygen sensitive material to determine the level of gases within the enclosed atmosphere.

Abstract: This invention is a data processing/visualization method which includes the software development and operation to apply to any multi-dimensional separation. The GC-MS analysis of diesel is an example to demonstrate this software development and operation. The steps of this method includes (1) displaying the total ion chromatogram obtained from a GC-MS experiment, (2) displaying each mass spectrum versus retention time, (3) selecting a normal paraffin family as the reference compound family for relative polarity display, (4) transforming every mass slice to line-up normal paraffin compound family in the same relative retention time (position), (5) rotating the axis to best display the two (multi) dimensional data.

Abstract: The invention relates to a method and an apparatus (herein referred to as a “gas sorption/desorption analyzer”) for measuring the gas sorption properties of substances (for example hydrogen sorption by metal alloys). Measurements include: Pressure Composition Temperature isotherm (PCT), Kinetic, Cycle-life, and density. Measurements are made by sorption of aliquots of gas to or from a sample of the substance. The amount of gas in each aliquot is determined from the gas pressure and temperature in calibrated reservoir volumes. The apparatus comprises components rated for operation up to 200 atm, a plurality of sensors covering a broad pressure range, and minimized volumes to enable accurate measurements of small samples. Aliquot pressures are controlled using a feed-back controlled pressure regulator that can also be used for constant pressure sorption measurements. The gas temperature is regulated using a temperature controlled enclosure.

Abstract: We disclose an apparatus and process for measuring the Formation Gas Pore Pressure in drilling cuttings samples in the test tube. The Apparatus consist of vertical holder for test tube, for placing the cutting sample and pipette for adding measurable quantity of liquid. (Note: “vertical holder for test tube and test tube” are disclosed in U.S. patent application Ser. No. 10/711,435 Horizontal Binocular Microscope for vertically gravitated and floating samples). The process consist in measuring the gas bubbles size and volume in the test tube and the height of liquid covering the bubble. This we can calculate the volume and the pressure of the gas emitted out of the pores. By adding/subtracting more liquid to the sample and increasing/decreasing the height and the pressure of the liquid on the pore the test is repeated and the measurements documented in the tables for math processing to obtain the error corrections and standard deviation of the measurements.

Abstract: An air or gas bubble detection system detects the presence of liquid in intravenous (IV) tubing. By detecting the presence of liquid rather than gas, false alarms due to micro bubbles or small air gaps between the sensor and the tubing are avoided.

Abstract: An apparatus for measuring compositional parameters of solid, liquid, and gas components of a mixture flowing in a pipe is presented. The apparatus combines three different compositional measurements (e.g., the speed of light (microwave), the speed of sound (sonar), and mass loading of vibrating tubes or absorption of radiation) simultaneously to provide a real time, multi parameter, compositional measurement of gas-entrained mixtures.

Abstract: Liquid separator for a gas analyzer and method for separating a liquid component from gas. The liquid separator comprises an input passage having an input end and an output end, an output passage having an input end and an output end, a wall formed of a gas permeable and liquid impermeable material separating the input passage and the output passage, means for introducing a gas sample containing liquid through the input end into the input passage with a first portion of the gas passing through said wall to the output passage and a second portion of the gas and the liquid remaining in the input passage, a vacuum means for flowing the first portion of the gas through the output end from the output passage to a measuring unit, a first conduit connecting the output end of the input passage and for conducting the second portion of the gas and the liquid furtheron with vacuum means.

Abstract: A probe 10,170 is provided that measures the speed of sound and/or vortical disturbances propagating in a single phase fluid flow and/or multiphase mixture to determine parameters, such as mixture quality, particle size, vapor/mass ratio, liquid/vapor ratio, mass flow rate, enthalpy and volumetric flow rate of the flow in a pipe or unconfined space, for example, using acoustic and/or dynamic pressures. The probe includes a spatial array of unsteady pressure sensors 15-18 placed at predetermined axial locations x1-xN disposed axially along a tube 14. For measuring at least one parameter of a saturated vapor/liquid mixture 12, such as steam, flowing in the tube 14. The pressure sensors 15-18 provide acoustic pressure signals P1(t)-PN(t) to a signal processing unit 30 which determines the speed of sound amix propagating through of the saturated vapor/liquid mixture 12 in the tube 14 using acoustic spatial array signal processing techniques.

Abstract: A system for measuring the permeance of a material. The permeability of the material may also be derived. The system provides a liquid or high concentration fluid bath on one side of a material test sample, and a gas flow across the opposing side of the material test sample. The mass flow rate of permeated fluid as a fraction of the combined mass flow rate of gas and permeated fluid is used to calculate the permeance of the material. The material test sample may be a sheet, a tube, or a solid shape. Operational test conditions may be varied, including concentration of the fluid, temperature of the fluid, strain profile of the material test sample, and differential pressure across the material test sample.

Abstract: A measuring apparatus and method for use in measuring diffusible hydrogen concentrations in materials, structures, and other objects. In an embodiment of the invention for use in welding applications, the measuring apparatus (10) includes a sensor assembly (20) that, with an included sealing member (40), defines a sample area (17) on a weld bead (16) from which hydrogen evolves into a sample volume (18) defined by the sealing member (40), a sensor housing (34) and a sensor (22) of the sensor assembly (20). The hydrogen reacts with a sensing layer (28) and a reflector layer (30) positioned on the end of an optical fiber (24), all of which are included in the sensor assembly (20) and are sealably positioned within the sensor (22).

Abstract: A soot sensor includes an insulator having a through-hole and a center electrode provided in the through-hole of the insulator so that a leading end of the center electrode protrudes from a leading end of the insulator and faces a discharge gap. A heating member is embedded in the insulator, and the distance between the heating member and the leading end of the center electrode is at least 10 mm.

Abstract: A ceramic laminate body, a gas sensor element employing such a ceramic laminate body and related manufacturing method are disclosed as including first and second ceramic sheets, made of material compositions different from each other, and an intermediate bonding layer, bonding the first and second ceramic sheets to each other so as to form a closed hollow space between the first and second ceramic sheets. The intermediate bonding layer has a multilayer structure including first and second unit intermediate layers laminated on each other such that innermost end portions of the first and second unit intermediate layers are displaced from each other to adapt a difference in degreasing contraction rates of associated component parts.

Abstract: Methods and apparati for measuring entrained gas content. One of the disclosed apparatus embodiments includes a chamber and piping for process fluid, the piping including two different sectors each comprising a density and temperature gauge having a pressure gauge located upstream and a second pressure gauge located downstream, the two sectors being operatively joined together by a pressure-changing device. The pressure measurement feature may be incorporated into the combination density and temperature gauge, eliminating the need for separate pressure gauges. Data generated by this invention reduces measurement error caused by the dissolving or exsolving of gases with changes in pressure of a fluid, while providing instantaneous measurement, through apparatuses that measure system conditions at each of two pressure states within a very short period of time. For instance, in the context of continuously coating a substrate, the method of this invention comprises: a.

Abstract: Bubble detection apparatus and method for a liquid dispensing system includes temperature compensation for increasing accuracy of the bubble detection as temperature of the liquid varies. In one embodiment, temperature changes cause corresponding changes in the liquid viscosity. A reference value or pressure signal that is used in a comparator circuit is adjusted or compensated for temperature changes of the liquid. The comparator compares pressure signals to the reference to detect bubbles in the liquid being dispensed.

Abstract: The present invention relates to a new concept in measuring the dissolved gas levels in supersaturated liquid streams. In particular, the new device is specifically applicable to the measurement of carbonation levels in soft drinks. The measurement is made by permitting the beverage to escape from the pressurized container to atmospheric pressure through a thin tubing. The gas escaping from the supersaturated beverage separates the liquid stream into alternating gas and liquid segments. The relative long term average length of the segments is directly related to the CO2 content of the beverage. The instrument is simple to operate, inexpensive, and needs no calibration; it is easily adaptable to presently used laboratory equipment, and is useful in production process control.

Abstract: A device for measurement of entrained and dissolved gas has a first module arranged in relation to a process line for providing a first signal containing information about a sensed entrained air/gas in a fluid or process mixture flowing in the process line at a process line pressure. The device features a combination of a bleed line, a second module and a third module. The bleed line is coupled to the process line for bleeding a portion of the fluid or process mixture from the process line at a bleed line pressure that is lower than the process pressure. The second module is arranged in relation to the bleed line, for providing a second signal containing information about a sensed bleed line entrained air/gas in the fluid or process mixture flowing in the bleed line.

Abstract: A test apparatus for measuring the air entrainment characteristics of a fluid includes a reservoir for containing the fluid, an aerator apparatus to cause air entrainment of the fluid, and a density meter to measure the effects of air entrainment on fluid density. The test apparatus enables in-situ measurement of the transient air entrainment behavior of the fluid. A corresponding method is provided.

Abstract: The invention relates to method for monitoring dissolved gases in liquid-filled high-voltage installations comprising a sealed separating vessel communicating with a liquid tank, wherein an equilibrium state of the liquid with the gas state prevails in the separating vessel during normal operation and liquid is pumped off from the separating vessel with a pump as to keep the liquid level at a predetermined height, including the following steps; Short-time interruption of the pumping action as to leave the equilibrium state and to increase the pressure in the separating vessel, and withdrawal of a gas sample from the gas phase above the liquid level in the separating vessel for the analysis thereof. The invention moreover relates to a method for monitoring dissolved and undissolved gases, wherein the method for monitoring dissolved gases is performed and undissolved gas is fed back into the separating vessel, and to a device for performing the methods according to the invention.