Real Time Automatic Calibration of Flow Meters for Real-Time Hydraulic Modelling

2014 ◽  
Author(s):  
Norense Okungbowa ◽  
Noorallah Rostamy
Keyword(s):  
Real Time ◽  
Calibration Method ◽  
Operating Conditions ◽  
Time Averaging ◽  
Flow Ratio ◽  
Flow Meter ◽  
Flow Meters ◽  
Detection Techniques ◽  
Time Calibration ◽  
Dependent Flow

Performance of flow meters is often a function of flow rate as well as properties (density and viscosity) of the fluid measured by the meters. Since comparison of flow meter readings is a key parameter in leak detection techniques, it is desirable that the readings from the flow meters are accurate and comparable. The idea behind real-time calibration of flow meters is to calibrate a flow meter (called the dependent flow meter) against another flow meter (called the independent flow meter) that is assumed to read correctly. The real-time calibration method is useful under two main conditions: i) when the reference flow meter has been calibrated to a high degree of accuracy and the flow readings from the meter are accurate; ii) when the pipeline operating conditions support the fact that the meter-in flow at one station equals the meter-out flow at the other station. By determining the deviation of the dependent flow meter reading from the independent flow meter reading, a time-averaged flow ratio is calculated. However, the flow ratio calculation and time averaging is only updated at prescribed conditions. The proper correction factor is ascertained and then applied to the dependent flow meter reading. The main advantage of using this technique is that the flow meter repeatability is reduced over time below the nominal accuracy of the dependent meter. Note that the term “calibration” in this context does not refer to the standard method of calibrating flow meter with a ‘prover’ but a technique to calculate correction multiplier for flow meter in other to improve the performance of hydraulic models.

A real-time calibration method for the systematic errors of a star sensor and gyroscope units based on the payload multiplexed

Optik ◽  
2021 ◽  
Vol 225 ◽  
pp. 165731
Author(s):  
Zhongguang Yang ◽  
Xiaocheng Zhu ◽  
Zhiming Cai ◽  
Wen Chen ◽  
Jinpei Yu
Keyword(s):  
Real Time ◽  
Calibration Method ◽  
Systematic Errors ◽  
Star Sensor ◽  
Time Calibration

A New Linearly Polarized Microwave Radiometer Calibration Source

2012 ◽  
Vol 500 ◽  
pp. 341-347
Author(s):  
Xin Biao Wang ◽  
Chang Zeng ◽  
Jing Li ◽  
Jing Shan Jiang
Keyword(s):  
Real Time ◽  
Microwave Radiometer ◽  
Noise Temperature ◽  
Calibration Method ◽  
Calibration Source ◽  
Radiometer Calibration ◽  
Time Calibration ◽  
Linearly Polarized ◽  
Calibration Device

This paper introduces a calibration device for microwave (millimeter and submillimeter) radiometer. The device can provide the microwave radiometer continuously variable linearly polarized noise temperature. The paper also introduces a real-time calibration method to achieve the microwave radiometer calibration, and the test of microwave radiometer sensitivity and linearity.

Dynamic Real-Time Calibration Method for Fiber Bragg Grating Wavelength Demodulation System Based on Tunable Fabry-Perot Filter

2015 ◽  
Vol 35 (8) ◽  
pp. 0806006 ◽  
Author(s):  
王鹏 Wang Peng ◽  
赵洪 Zhao Hong ◽  
刘杰 Liu Jie ◽  
陈俊岐 Chen Junqi ◽  
韩旭 Han Xu
Keyword(s):  
Fiber Bragg Grating ◽  
Real Time ◽  
Calibration Method ◽  
Bragg Grating ◽  
Time Calibration ◽  
Fabry Perot

Real-Time Estimation and Calibration of GLONASS Inter-Frequency Phase and Code Bias

2019 ◽  
Vol 73 (3) ◽  
pp. 746-762 ◽  
Author(s):  
Zhixin Yang ◽  
Hui Liu ◽  
Yidong Lou ◽  
Bao Shu ◽  
Longwei Xu ◽  
...  
Keyword(s):  
Real Time ◽  
Elevation Angle ◽  
Vertical Direction ◽  
Time Estimation ◽  
Calibration Method ◽  
Mean Value ◽  
Time Calibration ◽  
Calibration Methods ◽  
Code Bias ◽  
Frequency Phase

The frequency division multiple access (FDMA) strategy used in GLONASS causes inter-frequency phase bias (IFPB) and inter-frequency code bias (IFCB) between receivers from different manufacturers. The existence of IFPB and IFCB significantly increases the difficulties of fixing GLONASS ambiguity and limits the accuracy and reliability of GLONASS positioning. Moreover, the initial value of IFPB and IFCB may be unavailable or unreliable with the increasing number of receivers from different manufacturers in recent years. In this study, a real-time and reliable calibration algorithm of IFPB and IFCB based on multi-GNSS assistance is proposed by providing a fixed solution. Real-time IFPB rate and IFCB can be obtained using this algorithm without the initial IFPB and IFCB. The IFPB rate for all GLONASS satellites and IFCB for each GLONASS satellite are estimated due to different characteristics of IFPB and IFCB. IFPB calibration can be divided into constant and real-time IFPB calibrations to meet the different positioning requirements. Results show that constant IFPB rate has only 2 mm difference from the mean value of real-time IFPB rate. The IFPB rate and IFCB estimated by this algorithm have excellent stability, and the change in reference satellite cannot affect the results of IFPB rate and the stability of IFCB. The centimetre-level positioning results can be obtained using two calibration methods, and the positioning results with real-time calibration method are 10%–20% better than those with the constant calibration method. Under satellite-deprived environments, the improvements of multi-GNSS positioning accuracy with constant inter-frequency bias calibration gradually increase as the satellite cut-off elevation angle increases compared with GPS/BDS, which can reach up to 0·9 cm in the vertical direction.

scholarly journals A New Calibration Method for the Real-Time Calculation of Dynamic Safety Following Distance under Railway Moving Block System

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Deng Pan ◽  
Qing Luo ◽  
Liting Zhao ◽  
Chuansheng Zhang ◽  
Zejun Chen
Keyword(s):  
Real Time ◽  
High Speed ◽  
Calibration Method ◽  
Hyperbolic Function ◽  
High Speed Train ◽  
The Real ◽  
Relative Safety ◽  
Time Calibration ◽  
Study Results ◽  
Time Calculation

Only the actual following distance that is a little greater than the optimum safety following distance at any time can make the following train move in safety and efficiency. For this purpose, a new calibration method is studied for the real-time calculation of the dynamically optimum safety following distance. To cope with the complex situations of train following operation, the mathematic model of train deceleration operation based on the hyperbolic function with a variable acceleration control strategy is established to simulate the speed-changing behavior of high-speed train steered by the well-experienced driver. Using the evaluation of train behavior adjustment quality and the numerical analysis theory, we build the fitting function of the optimum absolute safety following distance changing with the following train’s velocity for the real-time calibration of safe following distance under absolute braking mode. And then, we discussed the real-time calculation of the optimum safety following distance under relative braking mode (i.e., the relative safety following distance). The study results will help a high-speed train to evaluate and optimize its own following behavior according to the current operation states of train following system, the actual following distance, and the absolute or relative safety following distance. The actual following distance is rationally controlled by the scientific adjustment of the following train’s behavior so that train following movement can be always safe, efficient, and smooth (comfortable).

Attenuation of an ultrasonic beam by suspended particles and range of acoustic flow meters in sewer networks

2012 ◽  
Vol 65 (3) ◽  
pp. 478-483 ◽  
Author(s):  
Frédérique Larrarte ◽  
Pierre François
Keyword(s):  
Suspended Particles ◽  
Operating Conditions ◽  
Wastewater Management ◽  
Flow Meter ◽  
Flow Meters ◽  
Wide Range ◽  
Theoretical Predictions ◽  
Ultrasonic Flow Meter ◽  
Intensity Decay ◽  
Sewer Networks

Ultrasonic flow meters are commonly used in wastewater management. Under certain circumstances, a reduction in the flow meter range may occur and cause significant error in the flow rate measurement. Attenuation due to suspended particles is one of the phenomena capable of reducing the flow meter range. The present paper examines attenuation resulting from re-suspended pond sediment over a wide range of concentration values. It appears that a formula established for sand suspensions provides a good estimate of ultrasound attenuation for these types of particles as well. Experiments conducted for wastewater under particle concentrations commonly encountered in sewer networks demonstrate that the attenuation by particles only contributes to a negligible extent towards intensity decay, in accordance with theoretical predictions. We also theoretically determine herein the operating conditions under which the range of an ultrasonic flow meter would be significantly reduced due to particle attenuation.

scholarly journals A Real-Time Calibration Method of Kinect Recognition Range Extension for Media Art

2018 ◽  
Author(s):  
Sunghyun Kim ◽  
Won-hyung Lee
Keyword(s):  
Coordinate System ◽  
Real Time ◽  
Digital Media ◽  
Recognition Rate ◽  
Measurement Data ◽  
Calibration Method ◽  
Depth Image ◽  
Media Art ◽  
Fast Recognition ◽  
Time Calibration

Kinect is a device that has been widely used in many areas since it was released in 2010. Kinect SDK was announced in 2011 and used in many other areas than its original purpose, which was a controller for gaming. In particular, it has been used by a number of artists in digital media art since it is inexpensive and has a fast recognition rate. However, there is a problem. Kinect create 3D coordinates with a single 2D RGB image for x, y value - single depth image for z value. And this creates a significant limitation on the installation for interactivity of media art. Because the Cartesian XY coordinate and the spherical Z coordinate system are used in combination, depth error depending on the distance is generated, which makes real-time rotation recognition and coordinate correction difficult above coordinate system. This paper proposes a real-time calibration method of Kinect recognition range expansion for useful application in the digital media art area. The proposed method can recognize the viewer accurately by calibrating a coordinate in any direction in front of the viewer. 3,400 datasets witch acquire from experiment were measured as five stances: the 1m attention stance, 1m hands-up stance, 2m attention stance, 2m hands-up stance, and 2m hands-half-up stance, which were taken and recorded every 0.5 sec. The experimental results showed that the accuracy rate was improved about 11.5% compared with front measurement data according to Kinect reference installation method.

scholarly journals Real-Time Calibration of Magnetometers Using the RLS/ML Algorithm

Sensors ◽  
2020 ◽  
Vol 20 (2) ◽  
pp. 535
Author(s):  
Guocan Cao ◽  
Xiang Xu ◽  
Dacheng Xu
Keyword(s):  
Parameter Estimation ◽  
Real Time ◽  
Calibration Method ◽  
Least Square ◽  
Estimation Methods ◽  
Recursive Least Square ◽  
Ml Estimation ◽  
Time Calibration ◽  
Complete Measurement ◽  
Calibration Algorithm

This study presents a new real-time calibration algorithm for three-axis magnetometers by combining the recursive least square (RLS) estimation and maximum likelihood (ML) estimation methods. Magnetometers are widely employed to determine the heading information by sensing the magnetic field of earth; however, they are vulnerable to ambient magnetic disturbances. This makes the calibration of a magnetometer inevitable before it is employed. In this paper, first, a complete measurement error model of the magnetometer is studied, and a simplified model is developed. Then, the real-time RLS algorithm is introduced and discussed in detail, and the unbiased optimal ML is utilized to improve the accuracy of the parameter estimation. The proposed algorithm is advantageous in correcting the parameters in real time and simultaneously obtaining unbiased parameter estimation. Finally, the simulation and experimental results demonstrate that both the accuracy and computational speed of the proposed algorithm is better than those of the widely used bath-processing method. Moreover, the proposed calibration method can be adopted for calibrating other three-axis sensors.

Investigation of the Use of Ultrasonic Flow Meters at Oil Refining Process Unit

2020 ◽  
pp. 7-11
Author(s):  
E.V. Glebova ◽  
◽  
A.T. Volokhina ◽  
E.A. Polikakhina ◽  
◽  
...  
Keyword(s):  
Flow Rate ◽  
Petroleum Products ◽  
Operating Conditions ◽  
Oil Refining ◽  
Process Unit ◽  
Flow Meter ◽  
Flow Meters ◽  
Pressure Losses ◽  
Oil Refineries ◽  
Ultrasonic Flow Meter

It is known that changes in the flow rate of the medium can directly affect the safety of the process of refining oil and petroleum products. Therefore, the use of high-precision flow meters is one of the safety barriers to prevent possible accidents and incidents. Unfortunately, the task of parametric measurement of the consumption of oil and petroleum products before and after their processing in most cases causes certain difficulties. For this reason, each specific measurement task should be approached from a different perspective, offering different means and methods of measurement, allowing to achieve the most reliable and accurate data on the measured flow rate. Operating conditions at the oil refineries place high demands on flow meters. Conventional orifice flow meters, which are often used to measure flow in the oil refineries, have certain disadvantages: they require frequent maintenance, process interruptions during installation, cause pressure losses in the pipe. Based on the experience of foreign companies in replacing insertion flow meters with clamp-on flow meters, it was decided to use non-invasive (non-contact) flow meters for medium measurement. The advantages of these flow meters are that there is no need to cut pipes, which practically eliminates the risk of leaks occurrence during installation. Also, the ultrasonic flow meter does not have direct contact with the measured medium, which allows avoiding contamination of both the flow meter itself and the medium, as a result, increasing the accuracy and durability of flow measurement at the site. Research objectives: substantiation of the possibility of operation of an ultrasonic flow meter at the oil refining site, recommendations for the use of various sensors, as well as selection of the optimal installation site for the device. The flow rate readings matched the previously established readings taken from the orifice meters. As a result, it is concluded that the ultrasonic flow meters can be used to measure the flow rate of stripped oil.

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