80 results about "Liquid density" patented technology

The invention discloses a single-ultrasonic-head sensor for measuring liquid density and liquid level height, which relates to the technical field of liquid level measurement and comprises a floater component, a reflection cavity component and an ultrasonic sensor component. The floater assembly is assembled on the reflection cavity assembly, the reflection cavity assembly is connected with the ultrasonic sensor assembly, and the ultrasonic sensor assembly is connected with the floater assembly through the reflection cavity assembly. High-frequency ultrasonic waves are transmitted and received through a single point, the sound velocity (density) and the ultrasonic wave return time difference (liquid level) are synchronously analyzed, the density and the liquid level of the urea solution are calculated, the problems of mechanical interference and data splitting are avoided, and the trepanning and cable cost is reduced; the shared high-precision temperature compensation module directly eliminates compensation deviation of the split system, and maintenance only needs single-point anti-crystallization treatment; and in combination with a cross validation algorithm (density liquid level logic mutual verification), the operation and maintenance cost is reduced while the data reliability is improved, and the method is particularly suitable for space-limited and highly-corrosive urea solution detection scenes.

The invention discloses a liquid density measuring device and method and electronic equipment, and relates to the field of density measurement, the device comprises a metal base, a metal vibration platform, a measuring pool and a driving sensor, the measuring pool comprises a glass sealing shell, a U-shaped tube, a reference oscillation tube, a vibration acquisition sensor and a temperature acquisition device, and the U-shaped tube is used for filling measured liquid; the reference oscillation tube is not filled with liquid; the U-shaped tube, the reference oscillation tube, the vibration acquisition sensor and the temperature acquisition device are all arranged in the glass sealing shell; the measuring cell is arranged on the metal vibration platform, and the metal vibration platform is arranged on the metal base; the driving sensor is arranged in the metal base and located below the metal vibration platform, so that the metal vibration platform is conveniently driven to generate mechanical oscillation. Through the glass sealing shell, the influence of the external environment is reduced, the density is calculated at a proper temperature, synchronous oscillation of the U-shaped tube and the reference oscillation tube is ensured, density compensation is ensured, and the liquid density measurement precision is effectively improved.

The application belongs to the technical field of liquid density detection, and discloses a base liquor density detection method for an automatic blending system and related equipment. The method comprises the following steps: acquiring a solvent capacity identifier of current base liquor to be delivered and a residual risk identifier of the last batch of delivered base liquor, judging whether a preset pollution risk time sequence combination exists in a delivery sequence; if the pollution risk time sequence combination exists, delivering the current base liquor to be delivered at a preset flow rate, and collecting a first density measurement value in a first measurement period; then, making the liquid in the delivery pipeline stand still for a preset length of time; then, delivering the current base liquor to be delivered at the preset flow rate again, and collecting a second density measurement value in a second measurement period; calculating a density difference value according to the first density measurement value and the second density measurement value; according to a comparison result of the density difference value and a preset dissolution effect determination threshold, confirming the true intrinsic density of the current base liquor to be delivered; and thus the accuracy and reliability of density detection are improved.

The application discloses a method for measuring liquid density by using optical active solution, which comprises a laser, a polarizer, a liquid to be measured, an optical active solution, a transparent water tank, an electronic balance, an analyzer and a light screen. γ The optical active solution is filled in the transparent water tank with a length of l, and the mass of the optical active solution is γ, the mass of the solute is γ1, and the density is ρ X A certain mass (X) of the liquid to be measured is added, and after being uniformly stirred, the optical activity α of the mixed solution is measured by rotating the analyzer and the light screen; the relationship between X and α is obtained, that is, the data are linearly fitted by using a graphing method, and the density ρ X of the liquid to be measured is calculated by the slope of the straight line. The application is a method for measuring liquid density, and has clear physical principle, simple measurement process, high measurement accuracy and high repeatability.

An acoustic wave sensor (1) for waves propagating in a liquid is optically sensitive to variations in the liquid's density caused by pressure changes associated with the passage of an acoustic wave. The sensor is designed to be threaded through a wall (102) of a pipe, for example, in a water distribution network. The sensor is useful for detecting liquid leaks at a distance from its installation location, or for adjusting the intensity of an acoustic wave used to unclog a deposit on a surface in contact with the liquid. (Abstract figure: Figure 2)

The application discloses a kind of water bottom waste liquid self-adaptive collection device and waste liquid collection method, belong to environmental protection technical field.The application includes with the cover opening device and cover closing device of waste liquid recovery barrel cover connection;Utilize the pressure and density variation of water to start cover opening device and cover closing device, realize the automatic opening and closing of waste liquid recovery barrel cover.The application is realized automatic control by spring mechanism and float action in working box.The application utilizes the pressure and waste liquid density variation of water, automatically adjusts spring pressure, to drive gear system to perform cover opening and closing operation, the design of eccentric hole ensures the unidirectionality and stability of gear movement, avoids the possibility of reverse movement or misoperation, enhances the reliability of device in complex underwater environment.

Methods, apparatus, and systems for determining a level of a liquid in a liquid-containing vessel are disclosed. The liquid-containing vessel may be fluidically connected to a displacer cage. The method may include obtaining, with a load measurement device, a weight force of a displacer suspended from the load measurement device and disposed within the displacer cage. The method may also include submerging the displacer into the liquid and obtaining, with the load measurement device, a net force acting on the displacer. The method may further include obtaining, with a liquid density measurement sensor disposed within the displacer cage, a liquid density at a first location of the liquid. The method may still further include determining, using, at least, the net force and the liquid density at the first location of the liquid, the level of the liquid in the vessel.

The utility model discloses a pressure type on-line liquid densimeter, which relates to the field of perchloric acid densimeters and comprises a densimeter body, a tank body is arranged on the top surface of the densimeter body, a second connecting pipe is fixed and communicated with the bottom of the tank body, and the bottom end of the second connecting pipe is fixed and communicated with the top of the densimeter body. According to the utility model, the first valve body is arranged, different pressures can be preset through the arrangement of the first valve body, density measurement can be carried out in a stable pressure environment, the stability and repeatability of a measurement result can be ensured, and the quality and reliability of data can be improved; the working pressure of equipment can be effectively stabilized through the arrangement of the first valve body, a sensor and a measuring element in the densimeter body are prevented from being damaged due to too high or too low pressure, the opening or closing state can be automatically adjusted according to the actual pressure condition in a pipeline through the automatic adjusting function of the first valve body, the stability and reliability of the system are ensured, and the practicability is high. And problems caused by manual misoperation or system faults are reduced.

The invention discloses a chemical liquid density measuring and preparing device and method. The device comprises a measuring assembly and a liquid feeding assembly. The measuring assembly comprises a density measuring container and a weighing sensor, the weighing sensor is configured to be capable of measuring the weight of the density measuring bottle, and a lowest liquid level sensor is arranged on the density measuring container; the liquid feeding assembly comprises a first rotary valve and at least two kinds of chemical liquid, the first rotary valve is connected with the density measuring container through a connecting pipeline, the first rotary valve comprises a first closing valve port and at least two liquid feeding valve ports, and the chemical liquid is connected to the corresponding liquid feeding valve ports through respective pipelines; a liquid flowmeter and a switch valve are arranged on the connecting pipeline, and at least one end, close to the density measuring container, of the connecting pipeline is fixedly arranged, so that the weight measurement of the density measuring container is not influenced by the connecting pipeline. According to the scheme, mixed liquid preparation and density measurement are integrated, high efficiency and convenience are achieved, and potential safety hazards do not exist.

The invention relates to a liquid level metering method of a liquid level meter, which comprises the following steps: receiving pressure data detected by a first pressure sensor and a second pressure sensor, and judging the position of an oil liquid level; calculating the inclination angle of the probe according to the pressure data; the distance between the first pressure sensors is corrected according to the calculated inclination angle, and the actual height is obtained; the liquid density between the first pressure sensors is calculated according to the received pressure data and the actual height, and the position of an oil-water interface is judged according to the calculated liquid density; according to the liquid density and pressure data, the distance between the first pressure sensor and the oil liquid level is calculated, and the height of the oil liquid level is obtained; the sum of the pressure intensity of the water and the pressure intensity of the oil is the detection result of the first pressure sensor at the tail end of the detection rod, the sum of the water layer height and the oil layer height is the liquid level height, the water layer height and the oil layer height are obtained, and the oil volume is obtained by comparing the tank capacity meter of the oil storage tank. The metering method is accurate in metering, high in precision and high in reliability.

The application discloses a kind of single ultrasonic head measuring liquid density and liquid level sensor, it is related to the technical field of liquid level measurement, including: float assembly, reflection cavity assembly and ultrasonic sensor assembly;Float assembly is assembled on reflection cavity assembly, reflection cavity assembly and ultrasonic sensor assembly are connected, and ultrasonic sensor assembly is connected with float assembly by reflection cavity assembly.The application transmits and receives high-frequency ultrasonic wave by single point, synchronously analyzes sound velocity (density) and back ultrasonic wave time difference (liquid level), and calculates the density and liquid level of urea solution, avoids mechanical interference and data fragmentation problem, reduces the cost of opening and cable;High-precision temperature compensation module is shared to directly eliminate the compensation deviation of split system, maintenance only needs single-point anti-crystallization treatment;Combined with cross-validation algorithm (density liquid level logic mutual inspection), while improving data reliability, reduce operation and maintenance cost, especially suitable for space limited, strong corrosion urea solution detection scene.

The utility model discloses a well fluid collecting device of a well logging standard well, which comprises an annular mounting cover connected to the end part of the well logging standard well, one side of the annular mounting cover is connected with a liquid density sensor and a U-shaped transmission pipe, and the U-shaped transmission pipe is connected with a first control valve and a cyclone hydraulic separator used for separating liquids with different densities. The high-density liquid output end of the cyclone hydraulic separator is connected with a well killing fluid transfer box through a first pipeline, the low-density liquid output end of the cyclone hydraulic separator is connected with a shaft outlet liquid collecting box through a second pipeline, the well killing fluid transfer box is provided with a power pump which is connected with an output pipe, the output pipe is connected with an extension pipe, and the first pipeline is connected with a second control valve. The extension pipe is connected with a third control valve.

An apparatus and method are provided for optimizing the use of gas hydrate inhibitors by combining real-time "dew point" measurement with quantum-chemical phase-change analysis. A gas hydrate inhibitor reduces gas moisture; by measuring gas humidity and identifying the "dew type" using two chilled-mirror sensors each equipped with an imaging camera, a "dew coefficient" (0–1) is calculated via quantum chemistry analysis of inhibitor solvation. This mesoscale coefficient is used to monitor fluid phase changes. A general relationship for the water / hydrocarbon "dew coefficient" is derived as a function of changes in Gibbs free energy of dew evaporation (inhibitor solvation), gas temperature and pressure, and gas / liquid density. By combining measured "dew point" and "dew type" with quantum chemistry data of phase transformations "dew coefficient", the optimal inhibitor injection rate is determined, minimizing inhibitor consumption while preventing hydrate formation.

The invention discloses a liquid density monitoring method and device, electronic equipment and a storage medium, and relates to the technical field of control, slurry differential pressure signals are collected by means of a preset differential pressure measurement assembly, the density is calculated, and meanwhile measurement, flushing and pollution discharge execution assemblies are connected into an automatic control system to form a closed-loop control process. Sediment accumulation caused by slurry solid content change in long-term operation can be reduced through flushing and pollution discharge, and differential pressure signal fluctuation is avoided; the density value can be dynamically corrected based on historical data and working condition parameters to improve the measurement accuracy, fault self-diagnosis and alarm prompting are achieved by setting fault judgment conditions, manual inspection and experience judgment are replaced, the response speed is increased, and the measurement accuracy is improved. The technical effects of reducing slurry sediments, stabilizing differential pressure signals, reducing the maintenance cost, improving the desulfurization efficiency, avoiding the non-planned shutdown of the system and enhancing the operation stability of the desulfurization absorption tower are achieved.

1. The name of the design product: table type density meter. 2. The use of the design product: for measuring liquid density, alcohol content, sugar content, salinity. 3. The design points of the design product: in shape. 4. The picture or photo that best indicates the design points: perspective view 1.

The application provides a method for measuring the saturated surface dry water absorption rate of concrete coarse aggregate, which mainly uses an oven, a metal mesh basket, a beaker, an electronic balance and other tools, constructs a quantitative relationship model of relevant parameters according to the mass change of the coarse aggregate before and after being soaked in different liquids, and calculates the saturated surface dry water absorption rate of the concrete coarse aggregate. The application is based on the pore structure characteristics and capillary adsorption characteristics of the coarse aggregate, uses the difference in the absorption capacity of the coarse aggregate for different liquids, and the difference in the density and the viscous coefficient of different liquids, and designs the method for measuring the saturated surface dry water absorption rate of the concrete coarse aggregate. The method has the characteristics of simple steps, low cost, reliable test, stable data, easy popularization and the like, overcomes the defects of the traditional method, such as large human operation error and serious subjective experience influence, and can be used for the research and development of automatic equipment and the design of software algorithm, and has good popularization and application value.

The invention provides a float type liquid level monitoring method and device, a medium and a product. According to the method, a control processing unit firstly obtains preset parameters of a floater, initial liquid density and a real-time height value of a height sensor, and a basic data system is constructed for subsequent calculation. And the control processing unit generates a reaction rate curve by using the initial liquid density and the chemical reaction rate equation, and deduces a curve of the mixed liquid density along with the time change through the reaction rate curve, so that the pre-judgment of the dynamic change of the liquid density is realized. Then, the control processing unit calculates the immersion depth in combination with the current density and floater parameters, the liquid level distance is obtained through the distance difference between the height sensor and the bottom of a floater, and finally the actual liquid level is calculated based on the real-time height of the sensor and the liquid level distance. According to the method, the density change is dynamically tracked, errors caused by the immersion depth of the floater are corrected in a targeted mode, the problem of monitoring deviation caused by the density dynamic change is effectively solved, and the accuracy of liquid level monitoring is improved.

The invention relates to a liquid level metering method of a liquid level meter, which comprises the following steps of: receiving pressure data detected by first pressure sensors at different heights on a probe and a second pressure sensor arranged at the top end of the probe, and judging the position of an oil liquid level according to the received pressure data; the liquid density between the first pressure sensors is calculated according to the received pressure data detected by the first pressure sensors, and the position of an oil-water interface is judged according to the calculated liquid density; the distances between the first pressure sensors and the oil liquid level are calculated according to the liquid density between the first pressure sensors and pressure data detected by the first pressure sensors; the height of the oil liquid level is determined according to the distance between the first pressure sensor and the oil liquid level and the height of the first sensor on the probe; the water layer height and the oil layer height are obtained by solving the liquid pressure calculation formula and the liquid level height calculation formula, and the oil volume is obtained by comparing the tank capacity table of the oil storage tank. According to the metering method, the metering accuracy can be improved.

The invention belongs to the technical field of floating and sinking, and discloses a floating and sinking multi-density-level heavy liquid density adjusting and preparing device which comprises a first liquid barrel. The first liquid barrel is used for preparing heavy liquid with target density; a first pipeline is connected to the outer side of the first liquid barrel, a liquid inlet and a liquid outlet of the first pipeline are communicated with the interior of the first liquid barrel, and a solution in the first liquid barrel enters the first pipeline from the liquid inlet; a first pump part and a density monitoring part are connected in series in the first pipeline; the first pump part is used for pumping the solution in the first pipeline to the liquid outlet and enabling the solution to flow back into the first liquid barrel; the density monitoring part is used for monitoring the density of the solution in the first pipeline; the first liquid barrel is connected with a first liquid conveying unit and a second liquid conveying unit; the density monitoring part continuously monitors the solution flowing in the circulation loop, online, real-time and global measurement of the heavy liquid in the first liquid barrel is achieved, the accuracy and reliability of density modulation or preparation are remarkably improved, and modulation or preparation of heavy liquid of various density levels can be achieved according to actual needs.

The invention discloses an MVR evaporator system which comprises an evaporator, a compressor, a liquid separation unit and a control unit. Wherein the bottom of a liquid separation cylinder of the liquid separation unit is provided with a liquid separation cylinder conveying port, the liquid separation cylinder conveying port is communicated with a bottom discharge port of the evaporator through a first branch, and the first branch is provided with a first bottom valve; the delivery port of the liquid separation cylinder is further connected with a second branch communicated with the outside of the system, and a second bottom valve is arranged on the second branch; the first density sensor is used for measuring the liquid density rho 2b at the bottom of the liquid separation cylinder in real time; the control unit is configured to control the opening and closing states of the first bottom valve and the second bottom valve at least based on rho 2b after liquid in the liquid separation cylinder is subjected to standing layering, so that heavy-component pollutants located on the lower layer and light-component pollutants located on the upper layer after standing layering are discharged to the outside of the system through the second branch, and the heavy-component pollutants located on the lower layer and the light-component pollutants located on the upper layer are discharged to the outside of the system through the third branch. And the liquid in the middle layer is conveyed back to the evaporator through the first branch. According to the evaporator system, the evaporator can still continuously evaporate under the condition of high concentration of wastewater, and the treatment efficiency of the system is greatly improved.

The present application relates to the technical field of ore pulp processing, and particularly relates to a kind of ore pulp and reagent mixing and settling device and working method thereof, device includes mixing reaction mechanism, screen mechanism, settling mechanism and mud outlet mechanism, mixing reaction mechanism includes reaction bucket and vortex guide plate in it, bucket cover and reaction bucket side wall are respectively provided with medicine inlet and feed inlet;Reaction bucket bottom is communicated with settling barrel by spiral discharge pipe;Settling mechanism includes settling barrel and water suction port, and water suction port inlet is arranged in settling barrel, and located above screen;Mud outlet mechanism includes spiral blade, mud outlet and mud pump.The present application is provided with spiral vortex guide plate and staggered side baffle, combined with spiral discharge pipe and discharge baffle, so that ore pulp and reagent complete sufficient mixing, stirring and reaction in conveying process;By setting multiple densitometers, the liquid density at each position in the settling barrel is monitored in real time, so as to automatically adjust according to the actual settling condition, thereby improving the settling efficiency and effect.

The invention discloses a crystal elutriation leg system and a crystal elutriation process. The crystal elutriation leg system comprises an elutriation water distribution section, a crystal mush elutriation discharging section and an elutriation settling separation section which are connected in sequence. And the elutriation water distribution section is provided with a distribution disc with special pore diameter distribution, so that elutriation water is uniformly distributed. The ascending velocity of elutriation water is designed to be larger than the maximum free settling velocity of crystals, so that the distribution disc is prevented from being blocked. In the elutriation settling separation section, the upward flow velocity of clear liquid is controlled to be smaller than the minimum free settling velocity of crystals, so that fine crystals and impurity mother liquor are elutriated, replaced and floated, and target large-particle crystals are settled and enriched in the discharging section. Through cooperative control of the three-section type structure and the key flow velocity, mother liquor impurity entrainment in a crystal product is greatly reduced, the crystal purity and granularity uniformity are improved, and the device is suitable for various crystal separation and purification systems with the solid density larger than the liquid density and has the advantages of being scientific in design, low in cost and high in automation degree.

A fluid product dispensing device comprising a metering valve mounted on a reservoir (1) containing at least one active ingredient suspended in a pressurized propellant gas having a liquid density at 21°C less than or equal to 1.20 g / cm3, said metering valve comprising a valve body (10) containing a metering chamber (20), and a valve (30) sliding axially in said valve body (10) between a rest position and a dispensing position, to dispense the contents of said metering chamber (20), said metering chamber (20) being, in the rest position of the valve (30), substantially isolated from said reservoir (1), said valve body (10) comprising at least one fluid passage opening (11), said metering valve defining a sedimentation volume V disposed below said at least one passage opening (11) in the inverted operating position, with said metering chamber (20) disposed below said reservoir (1),said sedimentation volume V being greater than or equal to 500 mm3 and less than or equal to 1000 mm3. "Figure for the abbreviation: Figure 2",

The invention relates to the technical field of liquid density measurement, in particular to a closed density sensor which comprises a pipe body, a first connecting pipe and a second connecting pipe, the first connecting pipe and the second connecting pipe are fixedly installed on the two sides of the pipe body, and a backpressure adjusting assembly and a second detection assembly are fixedly arranged on the side face of the second connecting pipe. A rectification one-way assembly and a first detection assembly are fixedly arranged on the side face of the first connecting pipe, the second detection assembly and the first detection assembly are the same in structure, the backpressure adjusting assembly comprises a valve body, and a mounting cavity, a matching cavity and a guiding cavity are formed in the valve body. By arranging the back pressure adjusting assembly, the fluid pressure in the whole measuring pipe section is actively maintained to be a set value higher than the liquid saturated vapor pressure and the gas precipitation critical pressure, precipitation of dissolved gas is prevented from the physical source, it is ensured that pure single-phase liquid exists in the measuring cavity all the time, and the measuring accuracy is improved. Therefore, signal fluctuation caused by bubbles is eliminated, and a stable differential pressure signal of real liquid density is reflected.

An apparatus and method are provided for optimizing the use of gas hydrate inhibitors by combining real-time "dew point" measurement with quantum-chemical phase-change analysis. A gas hydrate inhibitor reduces gas moisture; by measuring gas humidity and identifying the "dew type" using two chilled-mirror sensors each equipped with an imaging camera, a "dew coefficient" (0–1) is calculated via quantum chemistry analysis of inhibitor solvation. This mesoscale coefficient is used to monitor fluid phase changes. A general relationship for the water / hydrocarbon "dew coefficient" is derived as a function of changes in Gibbs free energy of dew evaporation (inhibitor solvation), gas temperature and pressure, and gas / liquid density. By combining measured "dew point" and "dew type" with quantum chemistry data of phase transformations "dew coefficient", the optimal inhibitor injection rate is determined, minimizing inhibitor consumption while preventing hydrate formation.

The invention relates to the technical field of desulfurization process control, in particular to a cross-tower coupling stability control system and method for viscose fiber spinning bath desulfurization. Wherein the feed flow, the tower top pressure and the absorption liquid density and temperature are obtained in real time to calculate the absorption liquid saturation degree, the feed flow change rate and the tower top pressure change rate, so that the gas change trend is judged, and the source sink sensing module is awakened in response to the judgment result of the gas sudden increase trend; gas propagation time and concentration load increment are calculated according to the gas concentration at the outlet of the reaction tower and the inlet of the absorption tower so as to determine the gas mass impact state, and a cross-tower cooperative control strategy is formulated based on the gas mass impact state. According to the invention, control islands of the reaction tower and the absorption tower are broken, accurate identification and grading regulation of impact air mass are realized, energy consumption and maintenance cost of instruments are greatly reduced while the absorption tower is not broken down and environmental protection emission continuously reaches the standard, and system safety, economy and operation stability are considered.

The application discloses a control method for foundation construction under no treatment condition of soft stratum, and comprises the following steps: S1, cleaning the site and lofting and positioning the foundation plane position; S2, arranging the inclinometer tube on at least one side of the foundation plane position; S3, excavating the foundation groove, continuously filling the stable liquid into the foundation groove during the excavation process, dynamically adjusting the stable liquid density rho according to the size of delta S until the foundation groove is completed; S4, in-situ casting or precasting the foundation hoisting to form the foundation in the foundation groove, and collecting the discharged stable liquid for subsequent repeated use; and S5, grouting, and stably connecting the foundation and the soft stratum after the grout consolidation. The application can monitor the deformation of the soft stratum in the foundation groove process in real time, dynamically adjust the stable liquid proportioning to realize the density adjustment, and realize the rapid, safe and environment-friendly construction.

The application belongs to the technical field of gas flow measurement, and discloses a hydrogenation machine hydrogenation quantity calibration system, a calibration method and a hydrogenation quantity determination method. According to the scheme, the liquid surfaces in the cavities of the communicating vessel are kept in the same horizontal plane, and the buoyancy principle is used. A floating body is fixed with a gas storage container and placed in the containing cavity of the communicating vessel. The floating body floats in the containing cavity and can freely rise and fall in the containing cavity. The gas storage container is below the liquid surface in the containing cavity, and a liquid level detection unit is arranged in the test cavity communicating with the containing cavity to detect the liquid level height of the test cavity. According to the difference between the liquid level height of the liquid in the test cavity detected by the liquid level detection unit before and after the hydrogenation machine fills hydrogen into the gas storage container, the liquid surface cross-sectional area of the communicating vessel and the liquid density in the communicating vessel, the first hydrogen quantity filled into the gas storage container by the hydrogenation machine is determined, and the hydrogenation machine is calibrated according to the first hydrogen quantity and the hydrogen quantity measured by the hydrogenation machine, so that the accurate calibration of the correction coefficient of the hydrogen quantity measured by the hydrogenation machine is realized.

The invention discloses a method for measuring the evaporation rate of an exposed deck fuel cabin under complex full working conditions, which comprises the following steps: when the fuel cabin is in a full working condition state, respectively collecting the state data of the fuel cabin at the beginning of measurement and at the end of measurement through a sensor; according to the state data of the fuel cabin, an LNG liquid phase density value, a gasification latent heat value and an LNG steam specific heat value are calculated through an empirical formula; according to the fuel cabin state data and the LNG liquid phase density value, the evaporation gas flow is calculated; the evaporation rate is calculated and measured according to the fuel cabin state data, the evaporation gas flow and the LNG liquid phase density value; according to the boil-off gas flow, the gasification latent heat value and the LNG steam specific heat value, calculating through an energy conservation rule to obtain standard boil-off gas flow; and the measured evaporation rate is subjected to standardized correction through the standard evaporation gas flow and the LNG standard state data, and the standard evaporation rate of the full-working-condition fuel cabin is obtained. According to the method, the evaporation rate of the exposed deck fuel cabin can be accurately measured under complex full working conditions.

The utility model discloses a testboard, and relates to the field of flowmeter testboards. The test board comprises a water storage tank, a measuring cylinder unit, a transfer water tank, an electric appliance control cabinet, a control unit, a water pump and an electric fitting drain valve unit. According to the test board, the measuring cylinder water inlet pipeline adopts a shared pipeline for water inlet and adopts a same outlet for discharging air, so that the same pressure and liquid density in each measuring cylinder are ensured, and the increase of large and small flow reference errors caused by pressure and volume changes is avoided; the closing time of the double-valve electromagnetic valve is quantitatively controlled through the electric appliance control cabinet, after the volume reaches 95% of the designated volume, the large valve is automatically closed through the double-valve electromagnetic valve, small-flow water supply reaches 100% of the designated volume, and the situation that when large-flow water supply is carried out, due to the fact that the flow speed is high and the speed is high, the flow rate is large is avoided; instant cut-off easily causes damage to a pipeline valve.