Three-phase gas–liquid–liquid flows are very common in petroleum extraction, production, and transport. In this work a dual-modality measuring technique is introduced which may be well applied for three-phase flow visualization. The measuring principle is based on simultaneous excitation with two distinct frequencies to interrogate each crossing point of a mesh sensor, which in turn are linked to conductive and capacitive parts of fluid impedance. The developed system can operate eight transmitter and eight receiver electrodes at a frame repetition frequency up to 781 Hz. The system has been evaluated by measuring reference components. The overall measurement uncertainty was 8.4%, which considering the fast repetition frequency of measurements is suitable for flow investigation. Furthermore, a model-based method to fuse the data from the dual-modality wire-mesh sensor and to obtain individual phase fraction of gas–oil–water flow is introduced. Here a parametrized model is fitted to the measured conductivity and permittivity distributions enabling one to obtain phase fraction from measured data. The method has been applied and tested to the acquired data from a mesh sensor in static and dynamic three-phase mixtures of gas, oil, and water. Fused images and quantitative values show good agreement with reference values. The newly developed dual-modality wire-mesh sensor has the potential to investigate three-phase flows to a good degree of detail, being a valuable tool to investigate such flows.

In this paper, a novel high-speed multichannel impedance measuring system in presented. The measurements are based on simultaneous excitation with two distinct frequencies to interrogate the multiple sensing point of a given sensor. Received signals are analogue-to-digital converted (with a DAQ card) and the amplitudes of each frequency are determined using FFT implemented in LabVIEW. The capacitive and conductive parts of impedance are calculated based on amplitude measurements. The developed system can operate 8 transmitter and 8 receiver electrodes at a frame repetition frequency of up to 781 Hz, i.e. single channels are sampled at 6,248 Hz. The system has been evaluated by measuring reference components. Deviations from references values are below 10% which considering the fast repetition frequency of measurements is satisfactory. The developed system was applied to visualize the fluid distribution over the surface of planar multipoint sensor. Two different liquids (oil and water) and air were evaluated and their spatial distribution over the sensor’s surface was correctly visualized.

This paper describes the development and application of a sensing platform which consists of fast conductance sensors and proper data acquisition and management software which aims at the investigation of two-phase flow parameters in pipelines. A number of sensing nodes are connected through a network which allows monitoring the flow at different pipeline positions. In addition, a data management Web-based platform is presented in order to store and manage the massive volume of data generated by data acquisition. The sensor electronics has been evaluated in temporal response and the capability to measure the parameters such as void fraction time series and structure velocities. The preliminary study of horizontal two-phase flow experiment is presented showing the capability of the developed platform to monitor flow parameters along a pipe. INDEX TERMS Liquid height measurement, sensing platform, two-phase flow, two-wire sensor.

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Cardiovascular disease is the leading cause of mortality in Brazil and worldwide, and ischemic heart disease accounts for a large portion of this concerning scenario. 1 Among its forms of presentation, acute coronary syndrome (ACS) has a wide range of severity. 2 However, the use of validated mathematical models of clinical prediction is essential and recommended in national and international guidelines for the management of patients with ACS. 3,4 With this stratification, high-risk patients may receive more aggressive antiplatelet and antithrombotic therapy and early invasive intervention, whereas lower-risk patients may receive less aggressive treatments. 3,5 Based on the Global Registry of Acute Coronary Events (GRACE) report, the GRACE score was designed with 8 variables analyzed on patient's admission, 6 5 semiquantitative ones (age range, heart rate, systolic blood pressure, plasma creatinine, and Killip class) and 3

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