Experimental Methods in Thermal Engineering

Code:

EM0053

Acronym:

MEET

Keywords
Classification	Keyword
OFICIAL	Heat Transfer and Fluid

Instance: 2012/2013 - 1S

Active?	Yes
Responsible unit:	Fluids and Energy Division
Course/CS Responsible:	Master in Mechanical Engineering

Cycles of Study/Courses

Acronym	No. of Students	Study Plan	Curricular Years	Credits UCN	Credits ECTS	Contact hours	Total Time
MIEM	30	Syllabus since 2006/2007	5	-	6	56	160

Teaching language

Portuguese

Objectives

BACKGROUND
In a world of growing demand in terms of job performance, it is necessary for the future engineers to have a well grounded knowledge in a wide range of scientific areas. To this objective, the laboratory classes are important because in them the theoretical concepts are reconciled with practice, contributing thus to consolidate the knowledge acquired in other courses.

SPECIFIC AIMS
This course aims to enable students to conduct experimental studies in thermal engineering. It is intended that they know measuring instruments and experimental methodologies typical of that area and understand the physical principles underlying them, with a view to their proper selection and use. It also seeks to awareness students to the uncertainty of the measurements and their implications for the planning of experiments and analysis of experimental results and representation. The laboratory work is intended to provide practice of the experimental study and consolidation of theoretical knowledge acquired during their training. The teamwork and the realization of written reports are skills that are intend that students develop.

PREVIOUS KNOWLEDGE
EM0016 Numerical Analysis
EM0019 Thermodynamics I
EM0024 Thermodynamics II
EM0029 Fluid Mechanics I
EM0034 Fluid Mechanics II
EM0037 Heat Transfer

PERCENTUAL DISTRIBUTION
Scientific component (establishes and develops scientific bases) – 80%
Technological component (apply to design and process operation) – 20%

LEARNING OUTCOMES
At the end of this subject students shall be able to:
-Perform uncertainty analysis calculations.
-Use the ESS program to perform general uncertainty analyzes and simulate some of the phenomena present in the experimental studies.
-Select temperature, velocity and flow rate measuring systems for a given application.
-Write technical reports.
-Determine experimentally some rheological characteristics of a viscoelastic fluid. Fit generalized Newtonian models, such as the five parameters Carreau-Yasuda model, to the experimental shear viscosity curve.
-Use flow meters such as the venturi, the orifice plate and rotameter and calculate their experimental pressure drop coefficients.
-Measure local flow velocities using a standard Pitot tube.
-Setting a given flow rate using a frequency inverter, recognizing the energy savings associated with this method.
-Determine experimentally curves of head, efficiency and power of centrifugal pumps.
-Measure temperatures by means of thermocouples using only a voltmeter and the thermocouple curve.
-Experimentally determine convection coefficients.

Program

Experimentation and Uncertainty Analysis:
Why is the experimentation necessary?; Basic concepts and definitions, statistical considerations in measurement uncertainty; uncertainty of a measured variable; overview of uncertainty, planning experiments, detailed analysis of uncertainties.

Temperature Measurements:
Thermometry based on thermal expansion, resistance temperature detectors (RTD), thermistors, thermocouples, effects of heat transfer and fluid velocity in the temperature measurement.

Velocity measurements:
Smoke or suspended solids; vane anemometers; thermal anemometry; Pitot tube; cups anemometer; ultrasonic anemometer; Laser Doppler anemometer; particle image velocimetry (PIV).

Flow measurements by pressure differences:
Measuring velocities in several cross section points; orifice plates, venturis and nozzles, V-cone meter, segmental wedge flowmeters; elbow Taps; Pitot tubes and area averaging units; laminar flowmeters, flow detectors by deflecting jet; weirs and flumes.

Other flow meters:
Target flowmeter, electromagnetic flowmeter, turbine flowmeter, vortex and fluidic flowmeter, variable-area, gap, and Vane Flowmeters, positive-displacement gas flowmeters, ultrasonic flowmeters, mass flowmeters Coriolis, mass flowmeters thermal, cross-correlation flowmeters, metering pumps ; Viewers flow indicators; guidance to select flowmeters.

Experimental works:
-Rheology of an aqueous polymer solution
-Critical radius of insulation
-Applying uncertainty analysis concepts
-Air-flow through an orifice plate
-Flow rates measurement
-Study of the characteristic curves of a centrifugal pump (pumps in series / parallel)
-Loss of heat by convection in 3D bodies
- LDA measurements - Flow through a sudden expansion (demo)

Mandatory literature

Coelho P. M.; Métodos Experimentais (notas de apoio e fichas de trabalhos e resultados experimentais), 2011
Béla Lipták; Instrument Engineers’ Handbook, CRC Press, 2003
Richard S. Figliola, Donald E. Beasley; Teoria e projeto para medições mecânicas. ISBN: 978-85-216-1572-9
Coleman, Hugh W.; Experimentation and uncertainty analysis for engineers. ISBN: 0-471-63517-0

Complementary Bibliography

Miller, Richard W; Flow Measurement Engineering Handbook. ISBN: 0-07-042366-0
Guide to the Expression of Uncertainty in Measurement, ISO, Genéve, 1995
Holman, J. P.; Experimental methods for engineers. ISBN: 0-07-118165-2
Ashrae; Fundamentals. ISBN: 1-883413-81-8
Robert P. Benedict; Fundamentals of temperature, pressure, and flow measurements
Kerlin, T.W.; Practical thermocouple thermometry, ISA, 199
ed. Robert A. Granger; Experiments in heat transfer and thermodynamics. ISBN: 0-521-44925-1

Teaching methods and learning activities

The course is divided into theoretical and practical lessons. In the lectures is exposed matters relating to experimental work, discussing their most relevant aspects. Practical classes are intended primarily to carry out laboratory work where students are faced with instrumentation and measurement techniques of the main physical quantities of Fluid Mechanics and Heat Transfer. Some application exercises are also discussed in these classes.

Software

EES - Engineering Equation Solver

Evaluation Type

Distributed evaluation with final exam

Assessment Components

Description	Type	Time (hours)	Weight (%)	End date
Attendance (estimated)	Participação presencial	56,00
	Total:	-	0,00

Eligibility for exams

Regular enrolled students, not exceeding the number of absences, according to the existing rules, and have obtained a rank not lower than 10 points in all components of evaluation (A), (B) and (C ).

Calculation formula of final grade

The final grade (FG) results from a combination of the following components:
(A) laboratory work and reports
(B) Performance on laboratory sessions (includes mini-tests (B1) and results sheet (B2))
(C) Final exam (minimum of 8 out of 20).

FG = 0.40 A + 0.15 B1 + 0.1 B2 + 0.35 C

The performance of the various elements of each group, in the teamwork, at the end of the semester will be evaluated by the other peers. This assessment will be reflected in the A component of the final grade.

Examinations or Special Assignments

not applicable

Special assessment (TE, DA, ...)

not applicable

Classification improvement

For the purposes of improve their grades, students can conduct a written test covering the generality of the matter, with a weight of 35%.