A Brief Introduction to Transport Phenomena: Momentum Transport, Mass Transport, and Energy Transport Kingsley Wong (S’20)

Home , Mass transfer, Transport phenomena

Preface: The purpose of these documents is to provide an approachable introduction to three critical concepts in chemical engineering: momentum transport, mass transport, and energy transport. More generally, these three topics comprise what is referred to as “transport phenomena” – or how “things” move. More specifically, engineers are usually most concerned with the following subtopics: fluid dynamics (momentum), mass transfer (mass), and heat transfer (energy). It’s an incredibly useful branch of physics and a solid understanding can help offer insight in predicting system behaviour over both time and space. Most systems can be described using a combination of the three (but not always all three). For example, studying how water flows through a pipe would only require the consideration of momentum transfer. On the other hand, if you were to flow a temperature-sensitive enzyme through the same pipe, it may be of interest to have an understanding of all three.

This document draws from coursework I did in NE 318: Continuum Mechanics, NE 336: Micro and Nano Systems Computer-Aided Design, CHE 361: Bioprocessing Engineering, their respective textbooks (listed below), and other online material that will be referred to as we go.

Textbooks:

1. Transport Phenomena (2nd edition.) – Bird, Stewart, and Lightfoot 2002

2. Bioprocessing Engineering: Basic Concepts (2nd edition) – Shuler and Kargi (2002)

Chemical Engineering at Waterloo offers courses that greatly expand on these topics: CHE 211: Fluid Mechanics, CHE 312: Mathematics of Heat and Mass Transfer, and CHE 313: Applications of Heat and Mass Transfer.

Hopefully this series of documents provide a foundation to think about, understand, and derive models for different systems you may come across in your future endeavours. As a general roadmap, these documents will cover the basic mechanism of and how to model each of the three variants of transport phenomena. At the time of writing this, there isn’t an absolute clear path yet, but it will surely straighten out as the document progresses.

As a final comment, engineering often doesn’t bother with the hard nitty-gritties of science and explaining everything. Approximations and assumptions are used, while a great deal of “hand-waviness” is also employed. Let’s have some fun!