5
1.3 Problem Statement
These days, various pipes and vessels are used in process, and it is difficult to know what type of flow is inside them especially without interrupting the process. Thus,
the systems have to be developed whereby the system will be able to view objects within these pipes without interrupting the flow.
The process tomography system requires the knowledge of various disciplines such as instrumentation process, and optics to assist in the design and development of
the system. Thus, more information gathering is required to gain the enough information about this system requirements and the design. The way around this problem would be
to place sensing electronics around the actual pipe or vessel, where the system will using laser based detection system.
By using these sensing electronics, we are able to take measurements and recreate an image of what is contained within the vessel or pipe. Electronics of this nature needs to
be created such that it is affordable and easy to operate. A laser source is used to emit the laser beam through the pipe, while optical receiver in the other end will pick up this
beam and convert the laser beam intensity into a current that furthermore will be converted to voltage by a current to voltage converter. Various types of current to
voltage converter needed to be built, implemented and tested for suitability and sensitivity.
This project is mean to investigate the process tomography, and how can be used to construct an image of a particle in a transparent square pipe. In selecting the
appropriate optical sensor, the characteristics of the light source and sensor must be investigated. Based on this, the transmitter, receiver and signal conditioning circuit of
the system will be designed and realized physically. The signal conditioning circuit will be combined with the data acquisition system. Image reconstruction will be done using
software created using LabVIEW and it can display the data in real-time.
6 The process involves projecting a laser beam through some medium from one
boundary point and detecting the level of light received at another boundary point. The Silicon Phototransistor transducer was used to measure the laser beam intensity. The
software that acquire the data from the data acquisition system will 1.4
Objective of The Project
Mainly, the objective of this project is to:
i Data gathering and information collection regarding the project
ii To select the circuit and design the circuit for the receiver and transmitter
circuit. iii
To design and implement signal conditioning circuits that are effective for receiving and processing the signals
iv To obtain the components and hardware for the project.
v To understand the image reconstruction algorithm.
vi To develop program using LabVIEW that can display the concentration
profiles for object flow in real time manner.
1.5
Scope of Work
To make sure the objective of the project can be achieved, the following scope of work is identified. The main criteria that needed are to obtain the data from the sensor
and processed the data to computer. Below is the scope of work that has been identified: i.
Familiarization with the operation and performance of optical tomography systems.
ii. To design an optical system model that can be used to measure the particle object
flow.
7 iii.
To design, construct, and test signal conditioning circuits to process the signals obtained from sensors.
iv. To develop a program using LabVIEW to reconstruct a cross sectional images in
order to determine the concentration profiles of the flowing particle inside the pipe.
1.6 Methodology