Key takeaways
- Original Uncodemy revision notes on Heat and Mass Transfer in 9 units plus a practice question list.
- Worked examples on a composite furnace wall, black body emission and a counter-flow heat exchanger.
- Composite walls, critical radius, fins and LMTD are common numericals.
- Not official university notes. Check your own syllabus before revising.
- Free download after a short form.
About these Heat Transfer notes
These are original Uncodemy revision notes for Heat Transfer, written by the Uncodemy trainer team in a clean handwritten style. They follow the topics found in the common Indian B.Tech Mechanical syllabus. They are not official university notes, not a textbook and not a copy of any university's material. Unit names, order and depth differ between universities (AKTU, state technical universities and autonomous colleges all use their own scheme), so check your own syllabus and tick the units you need before you start.
Many universities call this subject Heat and Mass Transfer. The notes cover heat transfer in depth and give a short unit on mass transfer, which some syllabi include.
Each unit has short definitions, key formulas in highlighted boxes, comparison tables, "remember" points and worked examples with the steps shown. A list of commonly asked practice questions closes the notes. These are practice questions based on common syllabus topics, not verified past papers.
What's inside the Heat Transfer notes
The PDF has 9 units plus a practice question list. Here is what each unit covers, so you can match it with your syllabus.
Unit 1: Modes of Heat Transfer
- Conduction, convection, radiation: how each mode works and its basic law (Fourier, Newton, Stefan-Boltzmann).
- Thermal properties: thermal conductivity and thermal diffusivity in plain words.
Unit 2: Steady One-Dimensional Conduction
- General conduction equation: the Laplace, Poisson and Fourier forms and when each applies.
- Thermal resistance: electrical analogy for plane walls, cylinders and spheres, with a worked composite wall.
- Critical radius of insulation: why adding insulation can first increase heat loss.
- Heat generation: temperature distribution in walls and cylinders with internal heat generation.
Unit 3: Extended Surfaces (Fins)
- Fin types and cases: long fin, insulated tip and convective tip.
- Fin performance: fin efficiency and effectiveness.
Unit 4: Transient Conduction
- Lumped system analysis: when Biot number is small enough to treat the body as one temperature.
- Biot and Fourier numbers: what they mean and how they are used.
Unit 5: Convection
- Free and forced convection: the difference and the role of the boundary layer.
- Dimensionless numbers: Nusselt, Prandtl, Reynolds and Grashof numbers.
- Useful correlations: standard correlations for common flow cases.
Unit 6: Boiling and Condensation
- Pool boiling curve: natural convection, nucleate, transition and film boiling.
- Condensation: film and dropwise condensation.
Unit 7: Radiation
- Radiation laws: Stefan-Boltzmann, Kirchhoff, Wien and Planck laws.
- View factor: reciprocity and summation rules and radiation between surfaces.
Unit 8: Heat Exchangers
- Types and LMTD: parallel, counter and cross flow exchangers and the LMTD method.
- NTU-effectiveness method: when to use it and how to apply it.
Unit 9: Mass Transfer
- Basics: Fick's law of diffusion and the analogy with heat transfer.
How to revise Heat Transfer
Heat Transfer is formula-heavy. Revise the ideas behind the formulas so you can pick the right one.
- Think in resistances: most conduction and combined problems become a series resistance circuit.
- Learn the meaning of each dimensionless number: Nu, Pr, Re, Gr, Bi and Fo are asked as short questions too.
- Practise LMTD and NTU together: solve the same exchanger by both methods once.
- Use absolute temperature for radiation: always convert to kelvin before using the fourth power.
- Solve the practice list: the 10 questions at the end of the PDF cover most long-answer patterns.
Exam focus: high-weightage Heat Transfer topics
These topics are common across syllabi:
- Composite walls and cylinders by thermal resistance.
- Critical radius of insulation for a cylinder.
- Fin temperature distribution and heat flow.
- Lumped capacity analysis.
- Radiation exchange and view factors.
- LMTD and NTU-effectiveness for heat exchangers.
Typical numericals worked in the notes
- Furnace wall of brick and insulation: heat flow works out to 440 W and the interface temperature to 490 degrees C.
- Black body at 1000 K: emissive power and peak wavelength.
- Counter-flow exchanger with hot oil and water: find the area by LMTD.
Check conduction answers with the heat conduction calculator and flow regime for convection with the Reynolds number calculator.
A 7-day revision plan for Heat Transfer
Use this plan in the week before your exam, after you have studied the subject once in class. Spend about two to three hours a day.
- Day 1: Unit 1 (Modes of Heat Transfer), Unit 2 (Steady One-Dimensional Conduction). Read, close the PDF, then write the key formulas and definitions from memory.
- Day 2: Unit 3 (Extended Surfaces (Fins)), Unit 4 (Transient Conduction). Read, close the PDF, then write the key formulas and definitions from memory.
- Day 3: Unit 5 (Convection), Unit 6 (Boiling and Condensation). Read, close the PDF, then write the key formulas and definitions from memory.
- Day 4: Unit 7 (Radiation), Unit 8 (Heat Exchangers). Read, close the PDF, then write the key formulas and definitions from memory.
- Day 5: Unit 9 (Mass Transfer). Read, close the PDF, then write the key formulas and definitions from memory.
- Day 6: redo every worked example in the notes without looking at the solution, then check each step.
- Day 7: attempt the practice question list at the end of the PDF in exam time, then go back to the units where you got stuck.
Who these notes are for
- B.Tech semester exams: third-year Mechanical students preparing for Heat Transfer or Heat and Mass Transfer papers.
- GATE ME basics: heat transfer is a regular GATE ME topic; conduction, fins, lumped capacity, radiation and heat exchangers are common. The notes cover basics and standard formulas; for GATE you still need a full question bank and previous papers from the official GATE site.
- Interviews: thermal, HVAC and plant roles often ask about modes of heat transfer, insulation, fins and heat exchanger types.
- Diploma and lateral-entry students: the plain language and worked steps make the units easy to follow, but check which topics are in your own scheme.
How to use these notes with your textbook
These notes are short on purpose. They are meant for revision, not for learning Heat Transfer for the first time. Study each unit once from your class notes, a standard textbook or the matching NPTEL course, and then use the PDF to revise quickly. If a topic in your syllabus is missing from the notes, mark it in your syllabus copy and study it from your textbook. If your teacher uses a different method or notation, follow your teacher in the exam. You can also request notes for another subject through the Uncodemy handwritten notes request page.
Download Heat Transfer Handwritten Notes PDF
Heat Transfer Handwritten Notes PDF
The PDF carries the same content as this page in a clean, print-ready layout, so you can read it offline and keep it for revision.
7 pages · 274 KB · PDF · Updated 5 Nov 2026