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Thermal flowmeters are used more and more widely in liquid flow measurement. In this paper, the mechanical shape of the thermal flowmeter is designed, and the optimal installation position of the thermal probe is determined. In the aspect of measurement mechanism research, three heating methods of the thermal probe are deduced: constant voltage heating method, constant current heating method, and constant power heating method. After reasoning, the constant current heating method is determined to be ideal, so the constant current heating method is selected to heat the speed-measuring probe in the experiment. By analyzing the power factor of convection heat transfer and residual heat source of the heating probe, it is concluded that the measurement range of the thermal flowmeter is 0.5–15 m3/d, the flow in this range is proportional to the electrical signal, and the relative error of measurement is within ±5.8%. According to the analysis of the experimental results, the thermal flowmeter has a simple mechanical structure and no redundant moving parts, which can prolong its service life when used on site. When considering industrial applications, the error may be greater than the laboratory error.

The inspection of wellbore casings has been extensively investigated owing to the increasing concern for safety in oil and gas production. However, efficient techniques for inspecting asymmetry defects have not been achieved. In this study, we developed a uniform circular array (UCA) to address the problem of borehole pulsed eddy current (PEC) techniques for asymmetry defect inspection in downhole casings. Based on the borehole PEC system model, the UCA developed with multiple independent probes was designed to achieve asymmetry defect inspection, and the three-dimensional magnetic field data of borehole depths, circumferential azimuths, and sampling times could be obtained. Furthermore, a multichannel data acquisition circuit, which guarantees downhole operation at 150 °C, was developed for the synthesized UCA. Using azimuth dimension information from the synthesized UCA at a certain borehole depth, we obtained an inspection approach for the width and penetration depth of asymmetry defects in the circumferential and radial directions, respectively. Simulations and field experiments were conducted, and the results demonstrate the effectiveness of the proposed method in inspecting asymmetry defects.

Transient electromagnetic (TEM) techniques have been proven to be efficient for nondestructive testing (NDT) operations due to their pulsed eddy-current properties. However, in the field of downhole measurements, harsh environments may significantly influence the NDT performance in downhole casings. In this paper, an empirical mode decomposition (EMD) method based on borehole TEM array signal denoising and baseline wander (BW) correction is proposed to compensate for the bad measurement conditions that affect downhole NDT. Based on the borehole TEM signal model, we investigated the principle of the EMD approach for the borehole TEM response, where the background magnetic noise and temperature drift effects were analyzed by considering the motion measurement and effective permeability. It was found out that although the BW can be effectively removed with the EMD approach, the performance of the signal denoising is closely related to the measurement speed of the downhole NDT sensors. To solve this problem, we proposed an array-based ensemble EMD method to improve the denoising performance of the borehole TEM signals by formulating a three-dimensional borehole TEM data structure, where the generation of the noise-aided data can be more efficient by employing the borehole TEM array. The performance of the proposed method was verified by applying it to a borehole TEM system for the NDTs of oil-well casings. In addition, field experiments were conducted, and the results demonstrated the effectiveness of the proposed method.

Borehole transient electromagnetic (TEM) array has proven to be efficient for the downhole nondestructive testing (NDT) of metal casings through the eddy-current property. However, restricted by bad downhole conditions, the simple increase of the receiving array is not sufficient enough for improving the downhole NDT performance. In this paper, we present a multiple-transmit focusing (MTF)-based borehole TEM system for the NDT of downhole casings. On the basis of the borehole TEM signal model, the response of the multiple-transmit array is derived by employing the matrix form of the borehole TEM response. It was shown that the excited magnetic field by the multiple-transmit array can be focused by weighting the current of each transmitter. Using this property, a modified linear constrained minimum variance-based multiple-transmitting array weighting method was proposed to realize the MTF. Moreover, a subarray partition approach was proposed to simplify the MTF realization, where the subarray weighting and mean square error were also analyzed. The MTF method performance was verified by applying it to a borehole TEM system for the NDTs of downhole casings. Finally, simulations and experiments were conducted, and the results demonstrated the effectiveness of the proposed method.

In order to improve the power quality of the power transmission system, engineers must measure the phase angle of the transmission line to evaluate the power quality. Therefore, this article measures the phase angle by measuring the real-time voltage signal and current signal of the single-phase transmission line. This design is considered from the two aspects of hardware and software as well as the upper computer and the lower computer cooperate to test. The whole system uses ARM as the core to measure and process the parameters of the transmission line, which combined with the characteristics of ARM for signal acquisition, analog-to-digital conversion, data processing. The lower computer uploads it to the upper computer MATLAB for programming calculation through serial communication, and it uses the cross-correlation function method to measure the phase angle between voltage and current to meet the design requirements. The above design has been proved through experiments that it can be applied to engineering practice. The cross-correlation function algorithm in MATLAB closely fits the measurement of the phase angle of the transmission line. It proposes a new method for the measurement of the phase angle and lays a solid foundation for the future phase angle optimization.

In all links of natural gas supply, storage and marketing, accurate measurement of flow is one of the most critical links. Due to the high requirements of gas flow measurement for the flow meter measurement system, not only high accuracy of the flow meter measurement is required, but also higher requirements for the measuring sensor. Therefore, this paper mainly studies the influence of sensor structure design and sensor drive waveform on the signal sent and received by the gas flowmeter in the process of natural gas supply. Through the analysis and research of the ultrasonic attenuation theory, the conclusion that the performance of the oblique probe sensor is better is obtained. And by analyzing the experimental data, it is verified that the sensor effect of the oblique probe driven by the pulse waveform in the driving circuit is the best.

Multiphase flow monitoring of the oil and gas production process is of great significance to the safety of oil and gas exploitation and production. Electrical capacitance tomography (ECT) is one of the most attractive technologies in the field of multiphase flow measurement due to the advantages of its non-radioactive and non-contact properties, good visualization, and low cost. We propose a reconstruction algorithm based on wavelet and richer convolution feature (W-RCF) for solving the problem of artifacts and edge blurring in ECT imaging. In the algorithm, the two-channel source images of Tikhonov regularization and Landweber are simultaneously decomposed by a three-level wavelet. On this basis, an image fusion rule combining Bayesian decision and maximum entropy threshold is established to optimize the wavelet coefficients at each scale. The rule can reduce image artifacts and compensate for the defects in the source images. Afterward, the fused images are input to the RCF network for training and testing, and ECT reconstructed images with higher quality are obtained. Based on the simulation and experimental results, it can be seen that the image reconstruction quality of W-RCF is significantly better than that of the linear back projection, Tikhonov regularization, Landweber, and convolutional neural network algorithms. Therefore, the W-RCF algorithm has higher accuracy and stronger adaptability for multiphase flow under different flow patterns, which provides an effective method of ECT image reconstruction and is more suitable for visual monitoring of multiphase flow in the oil and gas production process.

In the field of three phase flow testing, real-time and online wellhead production detection has become an indispensable trend for evaluating well production and well condition. At present, the production of most conventional oil fields in China is low, and there are many Wells with less than 10 m3 d−1. It is difficult to detect the flow of low-flow Wells with conventional metering methods. Therefore, this paper proposes to use thermal flowmeter temperature difference method to measure the flow value. First, COMSOL Multiphysics software was used to build the model of the thermal flow meter and set the size of the temperature probe, heating probe and velocity probe. Secondly, relevant parameters are set to simulate two steady state forms with different water content and different flow rate. Finally, the temperature changes of the velocity probe are simulated under the two conditions. The simulation results show that when the water content is the same and the flow velocity is between 0.0059 m s−1 and 0.059 m s−1, the temperature of the probe decreases with the flow velocity increasing, and the temperature of the probe increases with the flow velocity decreasing. At the same flow rate and water content between 0% and 100%, the higher the water content, the lower the temperature of the speed-measuring probe, and the smaller the water content, the higher the temperature of the speed-measuring probe. The simulation results show that thermal flowmeter can be competent for flow detection of low production fluid and low flow well, which provides the basis for the detection method of low production fluid in the future and lays the foundation for the design of thermal flowmeter.

Borehole transient electromagnetic (TEM) techniques are widely used for nondestructive evaluation (NDE) of oil & gas well casings with eddy-current diffusion properties. In this paper, we present a multiple-eccentric-sensor-based borehole TEM system for NDE of downhole casings. Using the borehole TEM signal model, the TEM responses of sensors with eccentric transmitting coils are analyzed. The response of the eccentric sensor contains sensitive information in the direction of eccentricity while offering an improved detection performance. Hence, multiple eccentric sensors at different azimuthal angles are used to image casing damage, allowing directional NDE of downhole casings to be realized while improving the inspection resolution of the casing circumference. The effectiveness of the proposed method is verified by applying it to NDE of oil & gas well casings in the Shengli Oilfield. The experimental results demonstrate that the proposed method can effectively realize directional NDEs of downhole casings and improve the detection performance of the borehole TEM system.

Background:Sand production is an important factor affecting reservoir exploitation. Excessive sand production affects the oil well life, causes the damage to the oil recovery device and brings serious hidden danger in the process of safety production.Objective:This paper presents a sand content computation model for the crude oil, which uses the power of sand production and Parseval theorem, develops a system to monitor the sand content.Method:The main problem of designing the mechanical structure and matching layer for sand sensor is introduced. Furthermore a contactless Doppler ultrasonic method is used to develop sand amount detection system‚ finally the system measurement accuracy is calibrated by the developed calibration system.Conclusion:The sand production computation model can describe the relationship between sand monitor output and sand amount; compute the oil sand carrying ratio. The sand sensor is installed on the outside of pipe, not directly contacted with the sand particles. Measurement accuracy of the sand production is higher than the same type instrument.

Electrical Tomography technology is widely used in the research and engineering practice of two-phase flow due to its advantages of non-radiation, non-intrusive and simple equipment structure. However, because of the electrical tomography sensitive field distribution of medium nonlinear (soft), the reconstructed images are often distorted, especially when faced with high conductivity and high dielectric constant two-phase flow (such as oil-field water of high salinity). Displacement current phase tomography (DCPT) is a new electrical tomography technology and it is proposed in 2017. An attractive feature of DCPT is that the relationship between the measured phase and the loss factor has a more extended linear range than the relationship between the measured capacitances in ECT and the permittivity distribution. In this paper, a 12-electrod DCPT with Landweber reconstruction algorithm is applied for gas-water two-phase flow imaging, and the reconstruction results are compared with electrical capacitance tomography (ECT) by numerical examples.

Borehole transient electromagnetic (TEM) techniques have been proven to be efficient for nondestructive evaluations (NDEs) of metal casings using eddy-current properties. However, physical limitations and bad borehole conditions restrict the use of eddy-current sensors, which makes downhole casing inspections very different from those of conventional NDE systems. In this paper, we present a uniform linear multi-coil array-based borehole TEM system for NDEs of downhole casings. On the basis of the borehole TEM signal model, a numerical multi-coil array approach using the Gauss&ndash, Legendre quadrature is derived. The TEM response can be divided into two independent parts related to the transmitting-receiving distance (TRD) and the observation time and casing thickness. Using this property, the signal received by the multi-coil array is weighted to cancel the influence of the TRDs of the different array elements to obtain the optimal response according to the linearly constrained minimum variance criterion, which can be shown to be identical to that of achieving the maximum signal-to-noise ratio. The effectiveness of the proposed method was verified by applying the uniform linear multi-coil array to a borehole TEM system for NDEs of oil-well casings. Field experiments were conducted, and the results demonstrate the effectiveness of the proposed method.

Sand production is a critical issue during oil and gas production from sandstone reservoirs. Uncontrolled sand production not only poses the risk of well failure, but also can cause extensive damage to surface and subsurface facilities such as tubing, pumps, valves and pipelines. In recent decades, research on sand production has been conducted in several fronts including sanding prediction, sand monitoring, sand control and well-bore integrity analysis to prevent or alleviate sand production and its consequences. This paper mainly focuses on sand monitoring based on non-intrusive ultrasonic sensor which produces real-time information that can be used for maximizing the safe production of hydrocarbon. We used non-intrusive ultrasonic sensor to monitor the acoustic signals generated by sand particles impacting the pipe wall, and developed a methodology for processing acoustic signals based on the kinetic energy of sand particles in the pipeline. Further, we developed a procedure for identifying and filtering acoustic noise from unrelated events. We validated the proposed methodology for signal processing against experimental data. The results indicated that the de-noising algorithm could filter out the noise from the acoustic data and the model was effective for assessing the sand rate.

Transient electromagnetic (TEM) techniques are widely used in the field of geophysical prospecting. In borehole detection, the nondestructive inspection (NDI) of a metal pipe can be performed efficiently using the properties of eddy currents. However, with increasing concern for safety in oil and gas production, more than one string of pipe is used to protect wellbores, which complicates data interpretation. In this paper, an auxiliary sensor-based borehole TEM system for the NDI of multipipe strings is presented. On the basis of the characteristics of the borehole TEM model, we investigate the principle behind the NDI of multipipe strings using multiple time slices of induced electromotive force (EMF) in a single sensor. The results show that the detection performance of NDI is strongly influenced by eddy-current diffusion in the longitudinal direction. To solve this problem, we used time slices of the induced EMF in both the main and auxiliary sensors. The performance of the proposed system was verified by applying it to an oil well with a production casing and liner. Moreover, field experiments were conducted, and the results demonstrate the effectiveness of the proposed method.

This paper introduces in detail the TMCS simulator in the Measurement while drilling system of rotary steering drilling tool in ground simulation Experiment system. Focusing on of TMCS measurement and control simulator, and the realization of steering drilling measurement simulation test system principle of work process KEYWORD: Steering drilling; TMCS measurement and control simulator; Measurement system of steering drilling; Ground simulation Experiment International Conference on Social Science, Education Management and Sports Education (SSEMSE 2015) © 2015. The authors Published by Atlantis Press 1049 target motion characteristics simulation. Selected TMCS measurement and control simulator consists of pre-positioning data steerable drilling threedimensional trajectory, WOB and torque drilling parameters such as generators and computer subsystems. The drilling parameter produce a variety of mixed uses a dedicated data signal modulation scheme, which can effectively reduce the direct digital synthesis technology brought drift, dislocation and loss. Control process shown in Figure 1. Figure 1. TMCS control process On the workstation simulator programming movement characteristics of rotary steering drilling assembly can also be preset orbit stored in document form workstation simulator, the simulator will be run in accordance with the information stored threedimensional simulation of down-hole drilling trajectory. 3 SIMULATED TEST STEERING DRILLING SYSTEM COMPONENTS AND WORKING PRINCIPLE The ground simulation experiment for in steering drilling measurement system, that components shown in Figure 2. The simulation system works as follows. Receive commands and Decoding module 地面 井下 Ground simulation computer Ground command transmission module Workstation simulator Negative mud pressure pulse signal Mud pressure positive pulse signa Analog generator for Inclination, azimuth, tool face angle, WOB drilling parameters Host PC (Down-hole control system) the measurement system of steering drilling Steering Drilling Servos Figure 2. Schematic diagram of steering drilling measurement system simulation experiment system Steering drilling system collects the real-time inclination, azimuth and tool face angle based on the output of the sensor data with from measurement data model of the workstation simulator , and analog outputs sent to the host PC (the down-hole control center),Which of the control software to collect data based on the real-time input wellbore trajectory calculation, measurement and steering drilling system solver of inclination, azimuth and tool face angle information were to do the filtering. Then inclination, azimuth and tool face angle deviation with the output of the state variable filter, will feedback to steering drilling measurement system solver error correction, ground simulation computer real-time acquisition host computer (the underground control center) of the D / A output, in a way to get uploading these amendments of the host computer (down-hole control center) by the downhole mud pressure pulse signal, and according to the mathematical model of the D / A output and a steering servo mechanism, solving actual servo movement at this time, feeding rotary steering drilling of BHA model for controlling motion to calculate the angular velocity of the solution, attitude, position, velocity and acceleration information, converted into real-time drilling parameters which ground engineers need ,and to be ground control instructions that were encoded for transferring by mud pressure module negative pulse signals. To be received with decoder module into digital signals, eventually propagat to the host computer for analysis and processing, control commands can be manipulated to manipulate steering drilling servo mechanism, in order to achieve automatic control rotary steering drilling. 4 CASE HISTORY: APPLICATION VERIFICATION AND GROUND SIMULATION RESULTS 4.1 Ground simulation computer HMI Shows the overall status of the system, can be set to synchronize the time to ensure on synchronization ground simulation computer and down-hole in realtime clock. Easy to storage and cleanup the historical data, remove historical data; Isoperimetric element of display operating temperature from down-hole BHA, rotating state, inclination, while the builtnegative mud pressure pulse control instructions. Figure 3. Ground simulation computer HMI Inclination, azimuth, tool face angle, drill press and other drilling parameters generator Encoder / decoder Workstation simulator CAN bus Negative mud pressure pulse signal