Charge‐coupled device based on optical tomography system for monitoring two‐phase flow

Abstract

An application of charge-coupled device (CCD) linear sensor and laser diode in an optical tomography (OPT) system is presented. The measurements are based on the final light intensity received by the sensor. The aim is to analyse and demonstrate the capability of laser with a CCD in an OPT system for detecting transparent objects in crystal clear water. The image reconstruction algorithms used were filtered images of linear back projection algorithms. These algorithms were programmed using LabVIEW programming software. Experiments in detecting transparent hollow straw were conducted. Based on the results, statistical analysis was performed to verify that the captured data were valid compared with the actual object data. The object's characteristics such as diameter also are observed. In conclusion, a non-intrusive and non-invasive OPT system that can detect transparent objects in crystal clear water is successfully developed. Introduction: The gas percentage in the liquid medium, gas flow rate, appearance and disappearance of gases, shape of gases and their diameters are imperative information for monitoring and process control. Petroleum refining systems, textile and fabric industries, oil and gas pipeline systems, geothermal wells, steam generation in boilers and burners and steam condensation all deal with two-phase flow which is in the form of gas bubbles and liquid [1]. Engineers need to monitor the condensation process or the distribution of steam bubbling to avoid any damage occurring in the high cost and high maintenance of their system. The optical tomography (OPT) system is considered as a hard-field sensor because the sensing field is based on the measurement of the attenuation or absorption of radiation [2]. For soft-field sensor, it depends on the changes of conductivity or permittivity of the objects that are being studied. OPT system provides many advantages compared with other soft-field sensors. OPT system gives a good spatial resolution of image reconstruction [3] and this sensor is appropriate for real-time monitoring system because it provides a high-speed data capture.

Ruby Stone Light Grade Inspection System Using CCD Linear Sensor – A Review

“…Transparent objects, like a glass window, admit almost all of the light in [29]. The application of CCD in tomography system was investigated by J. Jamaludin et al [25] [30] [31] [32]. Their research shows that Sony ILX551A CCD linear sensor was function efficiently with a 650nm wavelength laser diode.…”

“…Based on the basic principles used by the abovementioned research, this research will investigate the light intensity received by CCD after penetrating the ruby stone. The absorption of object density along the optical path diminishes light intensity exponentially, according to the Beer Lambert Law [32] [33]. The mathematical expression for light absorption processes [17] is shown in Eq.…”

A Study of Object Transparency Via Charge-Coupled Device Mathematical Modelling Assessment

“…In this quantifying object transparency experiment, the study was further observed with the selection of air bubbles as the subject. The which represents the air bubble's refractive index, was assumed to be [9]. Figure 8 is the modelled light striking the air bubble, which acts as the static object in the centre of the flow pipe.…”