Hands-on laboratory skills play a vital role in providing students with a sound understanding of the scientific fundamentals and their application in solving real-life engineering problems. One of the essential laboratory based courses taught at our Institute is Introduction to Measurements and Instrumentation. The design and implementation of such a course has been well documented in Western engineering education, but presents specific challenges in the Gulf region due to economical, social and cultural factors. This paper discusses the adaptation of corresponding Western courses to undergraduate mechanical engineering studies in the Gulf region. Laboratory exercises for temperature measurement and control are described, which consist of four modules, each building upon the other. In each module, students learn how to design an accurate measuring system, and process and interpret collected data. In the first module, the students are required to build a thermocouple reader using an AD620 instrumentation amplifier and to compare measurements with NIST reference tables. The second module is an introduction to LabVIEW, a graphical data acquisition programming language. The students are required to write a LabVIEW program to record multiple thermocouple signals from a heated plate under varying convective cooling conditions, using a high resolution temperature logger with on-board signal conditioning. The third and fourth modules focus on temperature control techniques. In the third laboratory exercise, the students are required to construct an electrical circuit using a low-power PCB relay and NPN bipolar transistor to develop a bang-bang linear temperature controller. The program created in module two is modified to have the heater operation automatically controlled for a fixed temperature set point. In module four, the students replace the bang-bang controller built in the previous lab with a commercially available PID controller and explore the differences between PID and linear temperature control systems. For each module, students are required to submit a formal report covering the theoretical background, the experimental procedure employed, uncertainty analysis, and conclusions and recommendations. An effective teaching strategy is outlined that covers the fundamental concepts of temperature measurement and control through carefully designed experiments, with sample results presented. Emphasis is placed on the tailoring of the course topics to engineering education in the Gulf region.
Measurement and control techniques in geothermal power plants
