252results about "Volume variation compensation/correction apparatus" patented technology

The invention relates to the technical field of flow measurement, and discloses a multiphase flow flowmeter dynamic compensation system, which comprises a multi-modal data acquisition module, a dynamic compensation module and a dynamic compensation module, the feature extraction and standardization module performs frequency domain conversion and feature extraction on the data to generate a fusion feature matrix; the graph structure modeling module constructs a graph model based on the fusion features and extracts graph feature vectors; the compensation optimization module obtains an optimal compensation parameter through Bayesian optimization; the flow estimation module generates a compensated flow value according to the optimal compensation parameter; and the adaptive feedback module calculates a flow residual error and updates the graph structure modeling module and the compensation optimization module. By introducing a dynamic compensation and self-adaptive feedback mechanism, the method can adapt to the change of the flowing state of the multiphase flow in real time, the precision and stability of flow estimation are effectively improved, the problem that a traditional method is difficult to quickly respond to flow pattern change and working condition fluctuation is solved, and the real-time performance and reliability of flow measurement are remarkably improved.

The invention discloses a double-frequency anti-interference ultrasonic water meter and a metering method thereof, and relates to the technical field of fluid metering. A 500kHz sound velocity reference channel is constructed in a self-transmitting and self-receiving mode of a single transducer, the sound path length under solidified pure water is calibrated through a factory, the current water quality sound velocity is calculated in real time in a zero flow state, the zero offset of a 1MHz main channel is dynamically corrected, and a high-precision temperature sensor is omitted. Meanwhile, online water quality diagnosis is realized by utilizing a double-frequency cooperation mechanism: turbidity is quantized according to the amplitude ratio of 500kHz and 1MHz signals (based on the characteristics of high-frequency scattering sensitivity and high low-frequency penetrability), and bubbles are detected according to the time domain volatility of the 1MHz signals; and dynamically optimizing the flow metering precision of the main channel according to a diagnosis result by combining a sound velocity compensation model (the sound velocity is inversely proportional to the turbidity) and a graded bubble compensation model (the sound velocity or the flow is corrected according to the volatility). According to the method, medium interference is effectively overcome, measurement reliability is improved, and real-time monitoring and reporting of basic water quality (turbidity and bubbles) are achieved at low cost.

The invention discloses a self-adaptive metering method of an ultrasonic water meter, which relates to the field of water meter metering, and comprises the following steps: acquiring real-time water temperature data and real-time flow velocity data of a measured fluid, compensating the sound velocity of ultrasonic waves based on the real-time water temperature data to obtain a first compensated sound velocity, based on the first compensation sound velocity, an excitation voltage self-adaptive adjustment strategy with ultrasonic wave head-wave ratio regulation and control and a measurement frequency dynamic regulation and control strategy are executed, secondary compensation is conducted through a built error curved surface compensation model with the water temperature and the flow velocity as indexes, and the initial flow value is corrected through an error compensation value; by means of multi-parameter collaborative real-time optimization, high-precision measurement and low-power-consumption operation under all working conditions are achieved, the measurement precision in the full-scale and full-temperature range is remarkably improved, and by intelligently adjusting the measurement frequency, cooperating with the flow rate change rate and error model feedback and dynamically balancing the dynamic response speed and static power consumption, the measurement precision is improved. And finally, double optimization of precision and energy efficiency is achieved.

The invention provides a temperature compensation method and system of a mass flowmeter, and relates to the technical field of mass flowmeters.The method comprises the steps that a space temperature field and a strain field covering a whole measuring pipe body are obtained, and a distributed heat-force coupling state is constructed; configuring a primary disturbance parameter set, projecting the primary disturbance parameter set to a natural vibration mode space, and constructing an equivalent temperature disturbance quantity; configuring the excitation frequency of dual-frequency vibration excitation; inputting a double-frequency response result into a temperature-flow decoupling model, and inversely constructing a temperature compensation factor; calculating an original estimated value of the flow, constructing a temperature compensation amount, fusing the original estimated value of the flow, and outputting a measurement result. The technical problem that in the prior art, due to the fact that single-point temperature measurement cannot accurately decouple the temperature effect under the complex working condition, measurement of the mass flow meter is inaccurate is solved, the space temperature field and the strain field of the whole measurement pipe body are obtained, self-adaptive compensation is conducted on sensitivity drifting of the measurement pipe, and the measurement accuracy is improved. And the measurement precision of the mass flow meter is improved.

A flow sensor for sensing fluid flow. The flow sensor includes an exterior, interior, a circuit board, and first and second ports. The first and second ports permit fluid to flow into and out of the interior. A Hall Effect Sensor in the interior detects the number of revolutions of an impeller. An electric coupler interfaces with the flow sensor and a transmitter for communication of the revolutions of the impeller to a controller. The controller determines the rate of fluid flow in a conduit. The controller issues a command signal to a component of a hydraulic system to alter the rate of fluid flow in the conduit.

The invention relates to the technical field of flow measurement, and discloses a ship fuel consumption whole-process online monitoring system and method.The system comprises a data acquisition module, a data regulation module, a temperature compensation module, a fuel consumption abnormity monitoring module, an energy efficiency evaluation analysis module and a data communication reporting module, and fuel flow and temperature data of a ship are acquired in real time; and a standardized data set is obtained after data normalization. According to the real-time fuel oil temperature, temperature-density coupling compensation is carried out on the volume flow, the volume error caused by thermal expansion and cold contraction is eliminated, and therefore the net fuel oil consumption is calculated. The consumption is compared with a preset fuel consumption threshold value in real time, and if the consumption continuously exceeds the threshold value, a fuel consumption abnormity identifier is generated. Afterwards, energy efficiency grade evaluation is carried out on the fuel oil use efficiency in combination with the real-time navigation state of the ship to obtain an energy efficiency analysis result, and the energy efficiency analysis result is transmitted to a remote monitoring platform through a ship communication channel; according to the invention, the accuracy of ship fuel consumption whole-process online monitoring can be improved.

The invention discloses an automatic temperature compensation circuit and method based on a thermal flowmeter, and relates to the technical field of temperature compensation, and the compensation circuit comprises a constant current source module used for driving the thermal flowmeter; the Wheatstone virtual bridge arm is used for acquiring a changed digital-to-analog converter output voltage value output by the controller, and performing voltage conversion on a first voltage and a second voltage which are output on the thermal flowmeter due to the change of the external temperature according to the output voltage value to obtain a third voltage; the digital-to-analog converter is used for performing correction compensation on the third voltage according to the correction compensation value calculated by the controller; and the differential amplification module adopts a differential amplifier to amplify the third voltage and the fourth voltage output by the thermal flowmeter, and outputs a compensated flow signal. The compensating circuit is simple in structure and higher in reliability and precision, and compared with a digital potentiometer, the output value of the Wheatstone virtual bridge arm is changed by using the output value of the digital-to-analog converter, so that the adjusting resolution is higher.

The invention relates to the technical field of ultrasonic metering, and particularly discloses a reciprocity-based ultrasonic metering structure, metering method and meter, the metering structure comprises a measuring pipe section, a first transducer and a second transducer, the first transducer and the second transducer are used for receiving or transmitting ultrasonic pulses; two ports of the measuring pipe section are respectively communicated through a first pipeline and a second pipeline which are connected in parallel, the first pipeline is provided with an inlet for a metered object to enter the measuring pipe section, and the first pipeline on two sides of the inlet is respectively provided with a first valve body and a second valve body; an outlet is formed in the second pipeline so that a metered object can be discharged from the measuring pipe section, and a third valve body and a fourth valve body are arranged on the portions, on the two sides of the outlet, of the second pipeline respectively. According to the metering method, the metering structure is adopted. The ultrasonic wave meter adopts the ultrasonic wave metering method based on reciprocity. The structure is reasonable, the design is ingenious, the measurement precision is greatly improved, and the production cost is reduced.

The invention discloses an ultrasonic water meter flow measurement and correction system based on Internet of Things, which relates to the technical field of water meter monitoring and comprises a sensing unit, a working data processing unit, a factor determination and analysis unit, a user management unit and an abnormity alarm unit. According to the invention, the sensing unit is used for multi-dimensionally collecting the working related data of the ultrasonic water meter, the working data processing unit is used for real-time processing and interference suppression, the quality of the obtained working data of the ultrasonic water meter can be improved, and the factor determination and analysis unit is used for determining the working data of the ultrasonic water meter by screening the performance related characteristics of the water meter, predicting the performance change trend and adjusting model parameters. The user management unit is convenient for a user to inquire data; the abnormal alarm unit ensures stable operation of equipment; the flow measurement precision can be improved on the whole, the system adapts to complex working conditions, intelligent management and fault early warning are realized, and powerful data support is provided for water affair management.

The invention belongs to the technical field of pipeline flow monitoring, and particularly relates to a long-distance water delivery pipeline flow monitoring method fused with terrain dynamic compensation, which comprises the following steps: selecting a long-distance water delivery pipeline reference point, and synchronously acquiring reference flow and static pressure; based on a multi-source data fusion technology, constructing a pipeline terrain elevation parameter model, generating a three-dimensional terrain matrix, calculating an elevation difference, a gradient and a curvature radius, and constructing a terrain correction matrix; on the basis of Darcy formula correction, down-slope section kinetic energy suppression and a down-slope section pressure compensation algorithm, head loss is corrected, potential energy conversion errors are suppressed, and water hammer effect interference is eliminated; the flow in the pipeline is corrected through edge calculation, and global flow balance verification is carried out; and pipe bursting or leakage points are positioned in an auxiliary manner based on an integrated visual platform. According to the method, the measurement precision of the pipeline flow under the complex terrain is effectively improved, and a high-precision and all-terrain self-adaptive intelligent monitoring and early warning platform is provided for a long-distance water conveying pipeline.

The application discloses a vortex frequency extraction and moisture phase separation flow measurement method combined with disturbance wave frequency characteristics, including a conductance ring sensor and a vortex flowmeter, comprising: a pressure sensor, a conductance ring sensor, a vortex flowmeter, a temperature sensor, an excitation electrode, a measurement electrode, a vortex generator, a piezoelectric probe, temperature, pressure and vortex signals s(t) are collected by a collection card, liquid film fluctuation signals δ(t) are collected by a high-speed AD-DA module and an FPGA, the conductance ring sensor 2 is used for dynamically monitoring the change of the liquid film thickness of the pipe wall, and then the fluctuation frequency, i.e., the disturbance wave frequency, is extracted, the vortex flowmeter is used for dynamically monitoring the vortex frequency, the relationship between the disturbance wave frequency characteristics and the vortex stability is utilized, and the extraction precision of the moisture two-phase vortex characteristic frequency is improved. The application utilizes liquid film fluctuation frequency information to extract the vortex frequency and correct over-reading, does not need to calibrate the liquid film thickness, has low requirements on the medium conductivity, and has a wide range of measurement medium.

The invention relates to the technical field of flow metering, in particular to a flow metering method and system for an ultrasonic water meter, and the method comprises the steps: analyzing an actual signal and a simulation signal of the ultrasonic water meter through an excitation transducer and a signal simulation module, and obtaining a signal effective time difference and an effective signal set of the ultrasonic water meter; obtaining a corrected ultrasonic propagation speed according to an ultrasonic propagation expression and the effective signal set, further analyzing an attenuation influence coefficient and constructing a flow prediction model; obtaining a flow velocity distribution compensation analysis model according to the flow velocity distribution compensation factor and the effective signal set, and deducing the analysis model to obtain a flow analysis model based on flow velocity distribution; the flow prediction model and the flow analysis model are combined to establish the all-working-condition flow analysis model, the all-working-condition flow analysis model comprehensively considers factors such as ultrasonic propagation characteristics, signal attenuation and flow velocity distribution, different measurement working conditions and environment conditions can be adapted, and accurate flow calculation is achieved.

The invention discloses metering equipment and a method for metering gas flow by using an ultrasonic sound velocity difference principle, and the method comprises the following steps: rectifying gas flow in a pipeline by using a rectifier assembly to stabilize a flow field, and then measuring the ultrasonic sound velocity difference of forward and reverse propagation of the gas flow by using an ultrasonic sensor in a sensing assembly; the detected pulse signals are transmitted to the intelligent flow totalizer assembly for operation, and the actual flow velocity and flow of the gas are obtained; a pressure sensor and a temperature sensor in the sensing assembly respectively collect a pressure signal and a temperature signal of gas in the pipeline, and synchronously transmit the collected pressure signal and temperature signal to the intelligent flow totalizer assembly; and after receiving the pressure and temperature signals, the intelligent flow totalizer assembly performs temperature and pressure compensation operation in combination with actual flow velocity and flow data of the gas to finally obtain the flow velocity and flow of the gas under the standard condition. The problems of low measurement precision and large pressure loss in the traditional technology are solved.

The invention relates to the technical field of gas flow measurement, in particular to a self-calibration MEMS (micro-electromechanical system) ultrasonic flowmeter based on an AI (artificial intelligence) algorithm, which adopts a high-frequency MEMS ultrasonic probe, a low-power-consumption driving circuit and an acoustic / electrical impedance matching structure to realize efficient transmission and stable excitation of ultrasonic signals; a low-power-consumption microcontroller and an AI compensation module are arranged in the flowmeter, temperature, pressure, time of flight (TOF) and actual sound velocity measured in a static gas state are fused, dynamic correction and intelligent analysis of gas flow are achieved, and the measurement precision in a low-flow-velocity section and under complex working conditions is remarkably improved. The device supports an event-driven low-power-consumption working mode, and long-term battery power supply and modular deployment can be realized; compared with a traditional PZT flowmeter, the scheme has better integration, stability and adaptability while reducing system cost and power consumption, and is suitable for new-generation intelligent gas meters and industrial gas flow monitoring scenes.

A method for improving flowmeter accuracy is provided. The flowmeter comprises at least one flow tube, at least one pickoff sensor attached to the flow tube, at least one driver attached to the flow tube, and meter electronics in communication with the at least one pickoff sensor and driver. The method comprises the steps of vibrating at least one flow tube in a drive mode vibration with the at least one driver and receiving a sensor signal based on a vibrational response to the drive mode vibration from the at least one pickoff sensor. An unremediated density is derived with the flowmeter. An unremediated mass flow is derived with the flowmeter. An extended drive gain is derived with the flowmeter. At least one flow variable is received. A density ratio is calculated. A plurality of wet gas coefficients is provided. A dry gas mass flow rate is calculated with the density ratio and at least one of the plurality of wet gas coefficients.

In a method for continuously supplying a metering device with different batches of one and the same liquid medium, a progressive addition of the medium of a new batch takes place during a batch change.

The invention discloses an external clamping type flow sensor medium temperature calculation method, and relates to the technical field of testing and metering, and the method comprises the steps: obtaining the outer wall temperature measurement values of two sensors through a temperature collection device; by means of double-temperature-probe averaging treatment, accidental errors of single-point measurement are effectively reduced, three heat transfer mechanisms of heat transfer, solid heat conduction and convection-radiation combined heat dissipation are constructed, a fluid dynamic criterion is introduced to accurately calculate a convection heat transfer coefficient, quantitative heat transfer models outside and inside the tube are constructed, and the heat transfer efficiency is improved. By introducing an empirical formula dynamically coupled with the environment wind speed and a fluid mechanics criterion correlation formula based on the Reynolds number criterion, scene self-adaption accurate calculation of the key heat exchange coefficient is achieved, iterative correction of fluid physical property parameters is combined, and through iterative calculation and real-time correction of the physical property parameters, the real-time correction of the fluid physical property parameters is achieved. A three-layer progressive error correction system of dynamic time correction, scene database correction and multi-dimensional anti-interference correction is established, and high precision and high reliability of temperature calculation are achieved.

The utility model discloses a compact type spindle body flow throttling device which comprises a shell, a spindle body throttling assembly is arranged in the shell and comprises a spindle body, one end of the spindle body is fixedly provided with a hemispherical fairing, the other end of the spindle body is fixedly provided with a tail contraction section, and the tail contraction section is fixedly provided with a hollow cavity. The other end of the tail contraction section is provided with an annular wing plate, flange rings are fixedly installed on the outer walls of the two ends of the shell, installation holes are formed in the flange rings, and a high-pressure pressure taking pipe is fixedly installed on the side wall of the end, fixedly provided with the shell, of the outer wall of the shell. A temperature sensor tube base is fixedly installed on the outer wall of the other end of the shell. By means of the structure, the good rectification effect on fluid is effectively achieved, the upstream straight pipe section is required to be short, and the advantages of being compact in structure, small in size and low in pressure loss are achieved.

The invention discloses a flow measurement and analysis system in a multiphase flow environment, and relates to the technical field of flow measurement, the system comprises a flow pattern identification module, a parameter acquisition module, a coupling mapping model module, an incremental learning module, a residual error correction module and a flow calculation output module; through cooperation of the flow pattern recognition module and the coupling mapping model module, compensation logic is dynamically switched, precise compensation of flow pattern and working condition adaptation is achieved, complex scenes such as medium component fluctuation and temperature and pressure sudden change are automatically adapted through the incremental learning module, the defect that in the prior art, adaptability to complex working conditions is poor is overcome, and the working condition accuracy is improved. According to the method, the working condition adaptation capacity of the system is improved, flow pattern conversion lag errors and sensor signal noise interference are corrected at the same time through a multi-scale residual error correction algorithm, the consistency and reliability of flow measurement results are guaranteed, finally, the precision and stability of multi-phase flow measurement are remarkably improved, and the actual requirements of industrial production are met.

The invention relates to the technical field of industrial process control and fluid dynamic measurement, and discloses a high-precision liquid flow detection method based on a sensor. The method comprises the following steps: arranging a sensor, initializing a measurement section, receiving an ultrasonic signal, extracting a phase difference updated along with time, executing two-point temperature calibration, converting liquid temperature and correcting sound velocity, and obtaining static propagation time delay and a theoretical phase; constructing a net phase difference, inverting an axial instantaneous flow velocity according to a propagation difference, and applying non-negative and upper bound constraints; collecting pressure fluctuation to estimate a turbulence equivalent speed and superposing the turbulence equivalent speed with the main speed; calculating the volume flow according to the cross section area and accumulating the volume; phase anomaly, temperature rate and pressure peak detection is carried out, and substitution, recalculation and interpolation are adopted respectively; and counting and normalizing the maximum values of the speed and the flow, and outputting the speed, the flow, the accumulated volume and a normalized curve.

The invention discloses a signal processing method and system of an aviation intelligent flow sensor. The method comprises the following steps: collecting real-time signal data and generating a flow characteristic data set; determining an initial measurement parameter based on a preset flow signal model; the real-time deviation between the initial parameter and the actual operation state is obtained, the initial parameter is subjected to self-adaptive optimization through a normalized weighted deviation correction formula, and an optimized measurement parameter is obtained; and performing dynamic intelligent processing on the sensor based on the optimized parameters, evaluating a measurement error variance and a precision fluctuation rate through working condition segmentation and a fuzzy control algorithm, and generating measurement stability information. According to the method, through non-dimensionalized deviation correction and dynamic working condition segmentation processing, the flow metering precision and the signal stability in the aviation complex environment are effectively improved.

The invention discloses a water flow testing method and device based on ultrasonic waves and a storage medium. The method comprises the following steps: acquiring a set number of measurement data by taking a set moment as a reference; calculating a measurement result according to the initial flow corresponding to each measurement data; acquiring multi-modal features of the measurement data, wherein the multi-modal features comprise time domain features, frequency domain features and energy features; calculating the confidence coefficient of the measurement result according to the plurality of multi-modal features; and correcting the measurement result according to the confidence coefficient to obtain a target measurement result. According to the technical scheme, accurate recognition of bubble interference is achieved, self-adaptive correction of the water flow measurement result is completed based on the bubble interference, and the water flow measurement reliability of ultrasonic waves under the complex gas-containing working condition is improved.

The utility model relates to the technical field of diaphragm gas meters, and discloses a diaphragm gas meter sampling and counting device which comprises a gas meter body, a diaphragm and a transmission device are arranged in the gas meter body, an output shaft of the transmission device extends out of the gas meter body from the side face, and an output wheel is arranged at the end, located outside the gas meter body, of the output shaft. A sampling wheel is arranged on one side of the output wheel, the sampling wheel is meshed with the output wheel, magnetic steel is arranged on the sampling wheel, a circuit board covers the sampling wheel, a sampling sensor is arranged at the position, opposite to the sampling wheel, of one side, facing the sampling wheel, of the circuit board, the sampling sensor is in wireless connection with the sampling wheel, and a display screen is arranged on the other side of the circuit board. According to the utility model, the output wheel and the sampling wheel are arranged outside the gas meter main body, and the sensor is arranged outside the sampling wheel, so that the influence of internal parts and environment on data transmission can be reduced, the collected data can be corrected, the display error is reduced, and the sampling accuracy is improved.

The application discloses a vortex flowmeter type flow measurement and control device long-term stable measurement and control method and system, relates to vortex flowmeter type flow measurement and control technology, and comprises the following steps: collecting vortex street signals generated by a generator and converting the vortex street signals into pulse signals, so as to obtain vortex frequencies according to the pulse signals; collecting pressure information and temperature information of a medium; establishing a temperature correction factor, a pressure correction factor and a corrosion scouring correction factor; and calculating a medium flow according to a calculated vortex flowmeter instrument coefficient; and comparing the calculated medium flow with a set target medium, and adjusting an opening degree of a valve assembly if there is a deviation. The application can solve the problem that the vortex flowmeter in the prior art is unstable in flow measurement and control due to the influence of temperature, pressure and corrosion on the generator during long-term operation.

A system for determining a gas flow in a gas delivery arrangement includes a data processing device, a flow meter detecting a flow of a gas mixture of a gas compound and an impurity gas compound, wherein the flow meter provides gas mixture flow information to the data processing device, a first compound concentration analyzer calibrated to a first impurity gas compound and detecting a concentration of the first impurity gas compound in the gas mixture, wherein the first compound concentration analyzer provides a first impurity concentration information based on the detected concentration to the data processing device, wherein the data processing device determines a target gas compound flow based on the gas mixture flow information received from the flow meter and the first impurity concentration information received from the first compound concentration analyzer.

A fluid measuring device (10) has two waveguides (22, 24) on a flow channel (12) and a first and a second signal converter element (26, 28) mounted to the waveguides (22, 24). The signal converter elements (26, 28) each comprise at least two signal converters (30, 32, 34, 36, 38, 40) for exciting surface acoustic waves in the waveguides (22, 24) that are arranged beside each other in a transverse direction (T) of the flow channel (12). To determining a flow rate through the flow channel (12) center signal data is measured with the center signal converters (30, 32) and side signal data is measured with the side signal converters (34, 36, 38, 40) of the first and second signal converter element (26, 28). From the measured center and side signal data, a correction coefficient is determined and a flow rate is determined from the measured center and side signal data and the determined correction coefficient.

The invention discloses an integrated intelligent flow sensor and a dynamic compensation system and method thereof.The sensor is of an integrated flow channel structure, a flow sensor, a temperature sensor and a pressure sensor are integrated, and compact design and signal isolation are achieved; the system calls a fluid physical property database by synchronously collecting three-parameter signals, and dynamically calculates the fluid density based on real-time temperature and pressure data; according to the method, the volume flow under the original working condition is dynamically compensated, and the high-precision volume flow and the directly-output mass flow are obtained. Flow measurement is fundamentally upgraded into'multi-parameter-material flow 'conversion based on the physical principle, and high-precision measurement is still guaranteed when the fluid state fluctuates.

Metering device (100) for a liquid medium, comprising: a first metering unit (10) having a first material chamber (12), a first material outlet (14) and a first metering piston (16) slidably arranged in the first material chamber (12) for ejecting the medium from the first material chamber (12); a second metering unit (20) having a second material chamber (22), a second material outlet (24) and a second metering piston (26) slidably arranged in the second material chamber (22) for ejecting the medium from the second material chamber (22); and a common material outlet (30) of the first and second metering units (10, 20). A gearbox (42) couples the first metering piston (16) and the second metering piston (26) to the drive motor (40).The two material chambers (12, 22) each with a piston (16, 26) can be operated alternately to eject material by a single drive motor (40) which drives the pistons in opposite directions, wherein the two material chambers (12, 22) can be connected to the common material outlet (30).

The invention relates to the technical field of oil and gas field moisture on-line metering, in particular to a moisture bimodal metering system based on vortex reinforcement for a gas well, which comprises a three-section type vortex separation pipe and a metering unit. The separation pipe adopts a spiral flow deflector and an umbrella-shaped flow stabilizer, so that the separation efficiency is enhanced, and the pressure drop is reduced; the metering unit realizes high precision through pressure-temperature compensation, and meanwhile, the accuracy is improved by combining a Coriolis flowmeter and density feedback calibration; the liquid level is controlled by adopting a fuzzy PID algorithm, and the response time is less than or equal to 2s. The device can remarkably improve the metering precision, and is suitable for efficient separation and precise metering of conventional gas field moisture.