99542 - Applied Thermal Engineering Laboratory M

Academic Year 2024/2025

  • Moduli: Gian Luca Morini (Modulo 1) Matteo Dongellini (Modulo 2)
  • Teaching Mode: Traditional lectures (Modulo 1) Traditional lectures (Modulo 2)
  • Campus: Bologna
  • Corso: Second cycle degree programme (LM) in Energy Engineering (cod. 5978)

Learning outcomes

At the end of the course, the student has the basic knowledge for carrying out thermal measurements and for the use of dynamic simulation software of the "building-plant" system. In particular, the student is able to: - Obtain temperature measurements, heat flow, velocity, heat power, overall heat transfer coefficients; - Calculate the uncertainty coupled to the thermal measurements; - Use commercial dynamic software for modeling "building-plant" systems.

Course contents

Introduction to the course. Temperature definition. Empirical scale: the Centigrade scale. Thermodynamic temperature. ITS-90. Subranges and fixed points. Calibration procedure of a platinum resistance thermometer.

Primary temperature labs. Secondary labs. Calibration of reference thermometers. The ITS-90 chain. RTD sensors. Characteristics of the RTD sensors. Wire-Wound RTD. Thin-Film RTD. Coiled element RTD. Materials. Linearity. Nomenclature. Response time. Callender-Van Dusen equation. Pt100 R/T simplified equation. Calibration of a primary RTD sensor. Two-wires RTD. Three-wires RTD. Four-wires RTD. Source of errors. Thermistors. NTC curves. Calibration of a NTC device. The Steinhart-Hart equation for accurate calibration. Thermocouples. Thermo-electric effects. Polynomial equations.

Cold Junction compensation. Exposed, Grounded, Sealed and Isolated junctions. Accuracy and response time. Compensation cables. Thermopile. Switch for multiple thermocouples. Introduction: what is Arduino. Embedded systems, microcontrollers, sensors, home automation. Ohm's law, resistors, LEDs, Arduino: hardware, firmware, software (the "sketch"). Arduino and the outside world: analog and digital ports, the serial interface.

Examples with DHT11 and DHT22 sensors.

Arduino's programming language: logic operators. Average temperature calculation. The ds18b20 NTC temperature sensor. How to associate an address to a ds18b20 sensor. The “one-wire” bus architecture. Manufacturing and calibration of thermocouples. IR thermocamera and black body.

Mechanical and thermal measurements: introduction to error theory. Uncertainty analysis. Concepts of accuracy, precision, measurement uncertainty.

Flow measurements in ducts. Methods for measuring volumetric flow and mass flow.

Pressure measurements.

Thermal energy measurements: heat meters.

Readings/Bibliography

Notes provided by the teacher and available on virtuale.unibo.it

Figliola R S and Beasley D E 2011 Theory and Design for Mechanical Measurements (New York: John Wiley & Sons)

Teaching methods

The topics will be covered both theoretically and practically through laboratory experiences.

Each student will be provided with an "Arduino" board and a set of electrical cables, temperature sensors, breadboards for solderless connections.

The Arduino board must be used by each student during laboratory exercises.

The Arduino board and all accessories delivered to the student must be returned at the time of the final exam.

Assessment methods

Each student will receive two topics to solve:

1) write an Arduino sketch to perform temperature measurements and associate an evaluation of accuracy, precision, uncertainty, etc. (a topic common to all students)

2) write an Arduino sketch to solve a specific problem using, among other things, temperature sensors. Each student will have to solve a different problem.

The two sketches must be sent to the teachers at least 7 days before the exam.

During the exam, the student is required to comment on the sketches produced, show how the sketches work using Arduino, and answer questions on the theoretical part of the course.

Teaching tools

Each student will receive materials to use for the laboratory test including an Arduino UNO board (or equivalent), various sensors and elements for making electrical connections between the board and sensors.

The lessons will be held with the aid of slides (powerpoint).

The use of the Aplied Thermal Engineering teaching laboratory at the Lazzaretto is foreseen.

Office hours

See the website of Gian Luca Morini

See the website of Matteo Dongellini