Heat Transfer Issues

Concepts and quantities of description of heat transfer issues. Fourier, Newton and Stefan-Boltzmann Laws. Calculation of steadystate heat transfer through multilayered flat and cylindrical walls using thermal resistance. Calculation of heat transfer through rods and ribs under various boundary conditions. Deter-mination of heat transfer coefficients for fluid flows inside and outside chan-nels. Determination of heat transfer coefficients for flowing flat walls. Cooling

of gas turbine blades. Heat transfer boundary conditions for gas turbine blades. Determination of temperature distribution in a model turbine blade us-ing Excel.

Lecture / verbal-visual method using modern multimedia techniques (presenta-tions with animation elements, illustrations and diagrams of sample solutions). Providing content for independent study in order to consolidate the knowledge defined by outcomes W1, W2, W3, W4

1. Laws describing heat transfer / 2

Basic concepts and definitions. Fourier's law, Newton's law, Stefan-Boltzmann law. Planck's distribution of black body radiation, Wien's, Kirchhoff's and Lambert's laws. Fourier-Kirchoff equation and unique-ness conditions for its solution. Real contact of two bodies.

2. Steady state heat transfer in multi-layer flat and cylindrical walls / 2

Using the knowledge of thermal resistances to calculate steady state temperature fields. Using the aspect ratio to solve steady state two-dimensional problems. Steady state heat exchange with the source.

3. Steady state heat transfer through bars and ribs. /2

Calculations of thermal quantities in the presence of various types of boundary conditions

4. Heat transfer in aircraft structures / 1+1

General characteristics of heat transfer. Determination of local and av-eraged heat transfer coefficients and temperatures (average, reference, adiabatic wall). Similarity numbers. Flow around aircraft profiles (distri-bution of the local Nusselt number around the circumference of the turbine blade).

5. Thermal loads of selected aircraft structures / 2

Historical view. Results of heat transfer tests in the wheel of the MiG-29 aircraft, icing of aircraft - results of the expert opinion (Mi-8, TS 11-Iskra).

6. Determination of heat transfer coefficients. /2

Determination of heat transfer coefficients during fluid flows inside channels and their external flows using criteria formulas for the Nusselt number.

7. Boundary conditions for heat transfer for blades / 2

Boundary conditions of heat transfer in the case of gas turbine blades and selected technical methods of blade cooling.

Class exercises consisting in group solving tasks and problem issues in order to consolidate knowledge determined by the outcomes W1, W2, W3, W4 and master U1 skills

1. Steady state heat conduction / 2

Steady state heat transfer in multi-layer flat, cylindrical and spherical walls.

2. Steady state heat transfer / 1+1

Heat transfer in bodies with simple shapes - rods and ribs.

3. Convective heat transfer / 2

Convective heat transfer including correlation formulas for the Nusselt number.

Laboratory exercises / practical method: implementation of issues in the form of work of research teams implementing the issue of measuring and interpret-ing phenomena in order to consolidate knowledge determined by the outcomes W1, W2, W3, W4 and master U2 skills.

1. Determination of thermophysical parameters of the material in dy-namic conditions / 2

Identification of thermal diffusivity and specific heat of solids using the instantaneous heat source method.

2. Calculations of the temperature field distribution in unsteady condi-tions /2

Determining the temperature field distribution in a turbine blade approx-imated by a flat fin using an Excel spreadsheet.

3. Determination of thermal diffusivity of solids / 2

Measurement of thermal diffusivity of solids under conditions of or-dered heat transfer.

4. Determination of the thermal conductivity of solids under condi-tions of steady heat transfer. / 2

Measurement of thermal conductivity of solid at a laboratory stand.

5. Modeling of heat transfer issues / 2

Investigation of the thermal loads of a selected aircraft structural ele-ment (in an uncooled rocket engine nozzle) by numerical simulations.

Basic:

1. Wiśniewski S., Wiśniewski T.S.: Wymiana ciepła. WNT, Warszawa 2010,

2. Wiśniewski S.: Obciążenia cieplne silników turbinowych. WKiŁ, Warszawa 1974,

3. Madejski J.: Wymiana ciepła w turbinach cieplnych. Ossolineum, 1988,

4. Terpiłowski J., Wiśniewski S.: Termodynamika. Zbiór zadań cz. II. Skrypt WAT, Warszawa 1974,

5. Zmywaczyk J.: wykłady z wymiany ciepła w postaci elektronicznej *.pdf, WAT, Warszawa 2012,

6. Instrukcje do ćwiczeń laboratoryjnych:

Materiały dydaktyczne – Wydział Mechatroniki, Uzbrojenia i Lotnictwa WAT

Complementary:

1. Kowaleczko G. i inni: Oblodzenie statków powietrznych. Wyd. ITWL, War-szawa 2005,

2. Koniorczyk P., Panas, Preiskorn M., Terpiłowski J., Zmywaczyk J.: Dia-gnostyka stanów awaryjnych koła samolotu MiG-29. Laboratoryjne badania rozkładu temperatury w kole przy modelowych warunkach wymuszenia cieplnego. Biul. WAT, Rok XLIV, Nr 1-2, 1995, str. 133-146,

3. Taler J., Duda P.: Rozwiązywanie prostych i odwrotnych zagadnień przewod-zenia ciepła, WNT, Warszawa 2003,

4. Cengel Y.A.: Heat and Mass Transfer- A Practical Approach, 3rd edition, McGraw-Hill 2007.

W1 / knows the basic laws and quantitative relationships in the field of heat transfer / K_W01,

W2 / has the knowledge necessary to understand the basic physical phenome-na in the field of heat transfer occurring in aircraft elements, devices, installa-tions and systems as well as in their operating systems and surroundings / K_W02

W3 / has structured and theoretically based knowledge in the field of heat transfer also during the flow of the medium in relation to selected aircraft structures / K_W08

W4 / has systematic knowledge of the construction of aircraft and space en-gines and issues of technical thermodynamics, including thermodynamic cy-cles and heat transfer. / K_W11

U1 / is able to obtain information from literature, databases and other sources to build simple models of heat transfer in aviation structural elements of air-craft and spacecraft / K_U01

U2 / is able to perform typical calculations in the field of heat transfer by con-duction, convection and radiation - processes occurring in aircraft structural elements, and is able to use properly selected computer tools to model thermal processes as well as to develop measurement results from experi-mental tests / K_U07

The course is passed based on the mark.

Laboratory exercises are passed based on the mark

A remote form of examination and assessment is allowed

It is permissible to conduct classes using distance learning techniques.

Completion of lectures is conducted in writing with test and problem questions with the possibility of including an additional oral test. W1, W2. W3, W4 ef-fects and additionally U1 and U2 effects are checked during the test.

The condition of admission to pass the lectures is obtaining positive marks for passing laboratory classes. When determining the final mark, mark for la-boratories with a weight not exceeding 50% may be taken into account.

The pass of laboratory classes for the mark is carried out on the basis of the average assessment of tests to check the preparation for the performance of individual exercises and the evaluation of written reports of the exercises.

A prerequisite for obtaining pass for laboratory classes is obtaining positive marks for answers to control questions and positive marks for written re-ports on the exercise.

The W1, W2, W3 and W4 effect is checked above all during lectures.

A satisfactory mark (dst) is awarded to a student who:

1. Knows and is able to independently present the basic concepts of heat transfer

2. Is able to independently state the basic laws of heat transfer

3. Is able to independently obtain information from literature, databases and other sources to build simple heat transfer models

A satisfactory plus mark (dst+) is awarded to a student who in addition to the dst assessment:

1. Knows and is able to independently provide at least 70% of the concepts and relationships related to the topics covered during classes, including the ability to independently provide and physically interpret the mechanisms of heat transfer in relation to solids and fluids, define temperatures (average, reference, walls adiabatic), provide the basic theorems of the similarity theo-ry, explain the impact of icing on the flight of aircraft

2. Is able to independently state the method of using the basic heat transfer relationships to assess the magnitude of thermal loads on aircraft structural elements in conditions of steady heat transfer

A good mark (db) is awarded to a student who in addition to the dst+ rating:

1. Knows and is able to independently state at least 90% of the concepts and relationships related to the topics covered during classes

2. Is able to present derivations of most relations composed of basic de-pendencies

A good plus (db+) mark is awarded to a student who in addition to the db rating:

1. Is able to independently present and explain how to derive most of the rela-tions composed of basic dependencies

2. Is able to formulate a theoretical description of a complex thermodynamic problem and is able to provide a method of solving it

A very good mark (bdb) is awarded to a student who additionally in relation to the db+ rating:

1. Is able to independently and correctly formulate a theoretical description of the problem of complex heat transfer and is able to provide a method of solving it

A student who does not meet the requirements presented above receives an unsatisfactory mark.

The effects of U1 and U2 are checked during the class exercises, during the performance of tasks and the preparation of laboratory exercises reports.

A satisfactory mark (dst) is awarded to a student who:

1. Knows and follows the rules of occupational health and safety in the labor-atory

2. Is able to independently define and interpret the values determined during the planned experiments

3. Is able to independently present the structure and describe the operation of the test stand

4. Is able to carry out a planned measurement (planned examination) in group cooperation and in consultation with the teacher

5. Is able, in group cooperation, to develop research results and present a report

6. Is able to use appropriately selected computer tools, in group cooperation, to model thermal processes and to develop the results of experimental re-search

A satisfactory plus (dst +) is awarded to a student who:

1. Is able, in group cooperation, to correctly interpret the result of the experi-ment

2. Is able to develop a heat transfer model in group cooperation

Good (db) is awarded to a student who:

1. Is able to carry out a planned measurement (planned study) in group co-

operation

2. Is able to analyze measurement error

3. Is able, in group cooperation, to correctly prepare research results and pre-sent a report

4. Is able, in group cooperation, to correctly interpret the results of computer modeling and present a report

A good plus (db+) is awarded to a student who:

1. Is able to set up a measurement stand (build a model / develop a virtual object)

2. Is able to independently develop and interpret research results

3. Is able to independently analyze the measurement error and justify its result

Very good mark (bdb) is awarded to a student who additionally in relation to the db+ rating:

1. Can perform all tasks independently and flawlessly

2. Is able to link the obtained result with a physical phenomenon characteristic of a given aircraft structural element

An unsatisfactory mark is awarded to a student who does not meet the re-quirements outlined above