Online Monitoring and Control of Flow rate in Oil Pipelines Transportation System by using PLC based Fuzzy‐PID Controller

https://depositonce.tu-berlin.de/bitstream/11303/8039/2/1-s2.0-S0955598616300875-main.pdf

Simulation-based determination of systematic errors of flow meters due to uncertain inflow conditions

The article is focused on the comprehensive analysis of the aerodynamics of air distribution devices with the combined heat and mass exchange, with the aim to improve the following hydro- and thermodynamic parameters of ventilation systems: flow rate, air velocity, hydraulic losses, and temperature. The inadequacy of the previously obtained characteristics has confirmed the need for more rational designs of air distribution systems. Consequently, the use of perforated plates was proposed to increase hydraulic losses for reducing the average velocity and ensuring a uniform distribution of the velocity field on the outlet of the device. The effectiveness of one of the five possible designs usage is confirmed by the results of numerical simulation. The coefficient of hydraulic losses decreased by 2.5–3.0 times, as well as the uniformity of the outlet velocity field for the air flow being provided. Based on the three-factor factorial experiment, the linear mathematical model was obtained for determining the dependence of the average velocity on the flow rate, plate’s area, and diameter of holes. This model was significantly improved using the multiparameter quasi-linear regression analysis. As a result, the nonlinear mathematical models were obtained, allowing the analytical determination of the hydraulic losses and average velocity of the air flow. Additionally, the dependencies for determining the relative error of measuring the average velocity were obtained.

Solving the Coupled Aerodynamic and Thermal Problem for Modeling the Air Distribution Devices with Perforated Plates

Today’s main energy sources such as natural gas, petrol, and petroleum products are transported via pipelines that are safe at long distances. Most of these pipelines are buried and their integrity...

Remote monitoring and control of LQR-PI controller parameters for an oil pipeline transport system:

Calculation of geometric flow profile correction factor for ultrasonic flow meter using semi-3D simulation technique.

https://depositonce.tu-berlin.de/bitstream/11303/8033/2/1-s2.0-S0955598615300200-main.pdf

Uncertainty evaluation for velocity–area methods

Ultrasonic clamp-on meters have become an established technology for non-invasive flow measurements. Under disturbed flow conditions, their measurement values must be adjusted with corresponding fluid mechanical calibration factors. Due to the variety of flow disturbances and installation positions, the experimental determination of these factors often needs to be complemented by computational fluid dynamics (CFD) simulations. From a metrological perspective, substituting experiments with simulation results raises the question of how confidence in a so-called virtual measurement can be ensured. While there are well-established methods to estimate errors in CFD predictions in general, strategies to meet metrological requirements for CFD-based virtual meters have yet to be developed. In this paper, a framework for assessing the overall uncertainty of a virtual flow meter is proposed. In analogy to the evaluation of measurement uncertainty, the approach is based on the utilization of an expanded simulation uncertainty representing the entirety of the computational domain. The study was conducted using the example of an ultrasonic clamp-on meter downstream of a double bend out-of-plane. Nevertheless, the proposed method applies to other flow disturbances and different types of virtual meters. The comparison between laboratory experiments and simulation results with different turbulence modeling approaches demonstrates a clear superiority of hybrid RANS-LES models over the industry standard RANS. With an expanded simulation uncertainty of 1.44e-2, the virtual measurement obtained with a hybrid model allows for a continuous determination of calibration factors applicable to the relevant mounting positions of a real meter at a satisfactory level of confidence.

https://www.mdpi.com/2673-8244/2/3/21/pdf?version=1658309654

Simulation Uncertainty for a Virtual Ultrasonic Flow Meter

Abstract. In this contribution it is intended to combine laser-optical measurements with numerical simulated flow profiles. This approach allows on-site calibration of installed flow meters and improves the accuracy of flow rate measurements under disturbed flow conditions. Since multiple pipe assemblies consecutively disturb the flow profiles, uncertain inflow conditions are considered in a polynomial chaos approach. Reynolds averaged Navier-Stokes equations (RANS) are solved to predict velocity profiles with inflow conditions from elbows out-of-plane with random distance to each other. Further, an optimization problem is solved in order to fit the simulated velocity profiles to the measurement data. The procedure is applied to di erent measurements from a test rig, for which the reference flow rate is known. The uncertainty of all measurements can be estimated very well. A reduction of the uncertainty by the procedure can however not always be assured, which is due to a lack of accuracy of the CFD simulations.

A coupled numerical and laser optical method for on-site calibration of flow meters


 When flow meters are installed in disturbed flow conditions caused by pipe configurations such as junctions or elbows, significant measurement errors can occur. With existing knowledge of the flow conditions, those errors can be corrected using suitable calibration factors. This paper presents a surrogate model based on computational fluid dynamics simulation results that can predict velocity profiles downstream of single and double elbows in- and out-of-plane. The simulated flow profiles are decomposed into a fully-developed and a disturbed part, which allows changing the Reynolds number and roughness of the pipe wall without performing additional simulations. Furthermore, proper orthogonal decomposition and interpolation using piecewise linear splines enables the real-time evaluation of the model for a wide range of curvature radii and distances between the elbows. By incorporating a measurement principle, calibration factors for different flow meter designs can be predicted. The model is validated on the example of an ultrasonic flow meter by comparison with measurement data obtained from a clamp-on flow meter.

Andreas Weissenbrunner

Papers

Simulation-based determination of systematic errors of flow meters due to uncertain inflow conditions

Uncertainty evaluation for velocity–area methods

Simulation Uncertainty for a Virtual Ultrasonic Flow Meter

A coupled numerical and laser optical method for on-site calibration of flow meters

A virtual flow meter downstream of various elbow configurations