Thermodynamics Refresher 2016

Introduction –  for UNENE course UN807 Power Plant Thermodynamics 

It is expected you know the material covered in this UNENE Thermodynamics Refresher for the UN807 course

Details

Instructor:  Robin Chaplin

UNENE students come from a wide variety of backgrounds and may or may not have taken the undergraduate courses that are expected in all the areas covered by the UNENE graduate courses. To ensure you are prepared for UN807, it is strongly recommended that you review and learn this material at the beginning of the course. Your professor will assume you have done so.

Power PlantThermodynamics covers the practical aspects of thermodynamics as it applies to the generation and utilization of steam in a steam cycle of a typical nuclear plant. The basic principles of thermodynamics are applied to such components as steam generators, steam turbines, condensers, feedwater heaters and reheaters. These principles are combined with the fundamentals of heat transfer and fluid mechanics in order to properly assess the performance of plant components. Material for the course has been derived from senior level courses at UNB in the field of power plant engineering which in turn use material from the CANDU operator and shift supervisor training courses. The formal course notes have been published in the UNESCO sponsored Encyclopedia of Life Support Systems.

About the Thermodynamics Refresher

• The refresher is intended to cover the following and to develop the necessary skills in using tables and charts.
  • Concept of Thermodynamic Cycles (T-s diagram)
  • Basic Thermodynamic Processes (T-s and h-s diagrams)
  • Use of Mollier Chart (h-s diagram)
  • Use of Steam Tables
• The basic schedule would be as follows:
  • Saturday: Morning Lectures on subject matter, Afternoon Assignment on use of tables and charts
  • Sunday: Morning Tutorial to answer questions and provide assistance where necessary, Afternoon Test on use of tables and charts
• It will be expected that the students will have read the notes in advance so the lectures will be a quick overview only. The focus then will be on the question bank problems and the ability of the students to be able to solve them. Assignment problems and test questions will be from the question bank. The test is intended to provide feedback only.

The courses taught at UNB from which UN807 was derived all require a first university level course in thermodynamics as well as in fluid mechanics (but not heat transfer). Fluid mechanics and heat transfer follow relatively basic concepts and much of what is required in UN807 is empirical so there is no need for these to be prerequisites. Thermodynamics however is much more complex in requiring a sound understanding of the fundamental theory and good skill in the use of steam tables and charts. Hence the need for a “Thermo Primer” for those students who do not have a background in thermodynamics that is those students who have not been through the traditional curriculum in mechanical or chemical engineering.

Thermodynamics is a very broad subject including thermodynamic cycles, chemical thermodynamics, statistical thermodynamics, etc. In the context of power plants it is just the area of thermodynamic cycles (using heat to produce work) that is of interest and with regard to conventional nuclear plants it is only the steam cycle that is of concern. This narrows the prerequisite requirements substantially. The first course in thermodynamics in Chemical Engineering at UNB is ChE 2012 Engineering Thermodynamics. This course is basically divided into steam cycles (including preliminary fundamentals) and gas cycles (including combustion constraints). By selecting those parts related to steam cycles (about half the course) we have the “Thermo Primer” for UN807.

COURSE MATERIAL AND STRUCTURE OF THERMO PRIMER

The Thermo Primer consists of the following:

• Thermo Notes
• Question Bank
• Solution Guide

The Thermo Notes are a straight copy of the relevant sections as given below of UNB Course ChE 2012 Engineering Thermodynamics

The first three sections are basic theory and the latter three sections are specifically related to steam cycles. (The full course has 12 sections).

The Question Bank has the same section numbers. Only those questions related to steam and water have been included. There is a Section 8 which includes the more advanced material arising from Section 7. It is the Question Bank that sets the standard for the course and hence the prerequisite knowledge and skill required. Hence the goal of the Thermo Primer is to achieve this standard.

The Solution Guide is to aid students in coming to grips with the material without the help of an instructor. It consists of five parts:

– Problem Solving Guide
– Sample Solutions
– Question Bank Attachments
– Answers to Problems
– Steam Tables

The problem solving guide gives directions on how to go about solving a problem such as where to start or what formulae or strategy to use. The worked examples show how to lay out a problem and what steps to follow. The answers are to give some assurance that the problems have been solved correctly. The Solution Guide has not been edited to match the Question Bank so does contain some irrelevant material It also contains attachments to some problems from the Question Bank and basic steam tables for reference.

STEAM TABLES AND CHARTS

It is required that students have good skills in interpreting and using steam tables and charts and to use appropriate judgement (for example subcooled water tables must be used at high pressures due to the compressibility of water). Due to the need for high resolution enthalpy-entropy diagrams (Mollier Charts) students must obtain these independently and make sufficient large scale (international size A2 is recommended) copies for their own use.

LEARNING STRATEGY

Some problems are easier and some more difficult than others so students should look at all problems in a particular subsection (for example 4.4 Heat Exchangers) and start with those that seem easy or are easily understood. If there is one marked “Example” there should be a fully worked solution to show how to do this type of problem. Those marked as “Test” or “Exam” questions are proven questions with refined wording and more consistent level of difficulty.

Problems in the earlier sections are foundations for those in the latter sections so these should be reviewed and only selected ones done so as to move on to the more comprehensive ones as quickly as possible. Most time should be spent on those problems in Section 5, Section 7 and Section 8. In essence the ability to do the problems in Section 8 is the prerequisite for UN807