An introduction to heat transfer

Flow Measurement Handbook is an information-packed reference for engineers on flow measuring techniques and instruments. Striking a balance between laboratory ideal and the realities of field experience, this handy tool provides a wealth of practical advice on the design, operation, and performance of a broad range of flowmeters. The book begins with a brief review of fluid mechanics principles, how to select a flowmeter, and a variety of calibration methods. Each of the following chapters is devoted to a class of flowmeters and includes detailed information on design, applications, installation, calibration, operation, and advantages and disadvantages. Among the flowmeters discussed are orifice plate meters, venturi meters and standard nozzles, critical flow venturi nozzles, positive displacement flowmeters, turbine and related flowmeters, vortex shedding and fluidic flowmeters, electromagnetic flowmeters, ultrasonic flowmeters, and coriolis flowmeters. Also covered are mass flow measurements using multiple sensors, thermal flowmeters, angular momentum devices, probes, and modern control systems. Many chapters conclude with an appendix on the theory behind the techniques discussed.

Flow Measurement Handbook: Industrial Designs, Operating Principles, Performance, and Applications

Guidelines for the use of ultrasonic non-invasive metering techniques

Single-camera stereo-digital image correlation (stereo-DIC) techniques have gained increasing attentions and demonstrated excellent prospects in the experimental mechanics community owing to their prominent advantages of cost-effectiveness, compactness, and the avoidance of the complicated camera synchronization. Using additional optical devices, e.g. a diffraction grating, a bi-prism or a set of planar mirrors, pseudo stereo images of a test sample surface can be recorded with a single camera. By correlating these stereo images using DIC, full-field three-dimensional (3D) shape and deformation can be retrieved. This review comprehensively summarizes the historical development, methodologies, strengths and weaknesses of the diffraction grating-based, prism-based, four-mirror-adaptor-based single-camera stereo-DIC techniques, and the recently proposed novel full-frame single color camera-based stereo-DIC technique for full-field 3D shape and deformation measurement. The optical arrangements, principles and calibration procedures of these single-camera stereo-DIC techniques are described in detail. Since high-speed deformation measurement is efficiently achieved by combining the single-camera stereo-DIC with one high-speed camera, single-camera stereo-DIC techniques show great potential in impact engineering, vibration and other dynamic tests.

Review of single-camera stereo-digital image correlation techniques for full-field 3D shape and deformation measurement

Binocular vision calibration is of great importance in 3D machine vision measurement. With respect to binocular vision calibration, the nonlinear optimization technique is a crucial step to improve the accuracy. The existing optimization methods mostly aim at minimizing the sum of reprojection errors for two cameras based on respective 2D image pixels coordinate. However, the subsequent measurement process is conducted in 3D coordinate system which is not consistent with the optimization coordinate system. Moreover, the error criterion with respect to optimization and measurement is different. The equal pixel distance error in 2D image plane leads to diverse 3D metric distance error at different position before the camera. To address these issues, we propose a precise calibration method for binocular vision system which is devoted to minimizing the metric distance error between the reconstructed point through optimal triangulation and the ground truth in 3D measurement coordinate system. In addition, the inherent epipolar constraint and constant distance constraint are combined to enhance the optimization process. To evaluate the performance of the proposed method, both simulative and real experiments have been carried out and the results show that the proposed method is reliable and efficient to improve measurement accuracy compared with conventional method.

Tao Zhang

Papers

Three-dimensional feature parameters measurement of bubbles in gas–liquid two-phase flow based on virtual stereo vision

On fluctuation of the dynamic differential pressure signal of Venturi meter for wet gas metering

Research the wet gas flow measurement based on dual-throttle device

Analysis of viscosity effect on turbine flowmeter performance based on experiments and CFD simulations

Wavelet denoising applied to vortex flowmeters