![]() |
![]() |
![]() |
![]() |
![]() |
Department of Architecture & Civil Engineering, Unit Catalogue 2006/07 |
AR40279 Thermofluids |
Credits: 6 |
Level: Masters |
Semester: 2 |
Assessment: EX100 |
Requisites: |
Before taking this unit you must take AR40215 |
Aims: To provide an introduction to the First and Second Laws of Thermodynamics and their implications for the use of energy in buildings.
Learning Outcomes: At the end of the unit, the student should be able to demonstrate: * an understanding of the 1st law of thermodynamics and its application to open and closed systems * an understanding of entropy * an ability to apply a knowledge and understanding of property relationships for pure substances to simple power, refrigeration and heat pump cycles * an understanding of the 2nd law of thermodynamics and thermodynamic efficiency * an understanding of psychrometrics, and an ability to analyse air conditioning processes * a knowledge of vapour power processes * a knowledge of refrigeration and heat pump systems * a knowledge of types of compressors, their characteristics, and their use in air conditioning systems The movement of energy and fluids in systems and buildings. The student will also be able to demonstrate: * a systematic understanding of this knowledge, and a critical awareness of current problems and/or new insights, much of which is at, or informed by, the forefront of this area of professional practice; * conceptual understanding that enables the student to evaluate critically current practice and new developments, and propose new solutions; * an ability to deal with complex issues both systematically and creatively, make sound judgements in the absence of complete data, and communicate their conclusions clearly. Skills: Advanced analytical techniques related to use of energy in buildings. Content: Power generation and the environment. Energy resources and the effects of fossil fuel combustion. Renewable energy sources and their possibilities for future use. Definitions, 1st law of thermodynamics for closed systems, thermodynamic properties of the perfect gas, relationship between internal energy and specific heat at constant volume. Work transfer in closed systems for constant volume, constant pressure, hyperbolic and polytropic processes; adiabatic reversible process for perfect gas. 1st law of thermodynamics for open systems and the Steady Flow Energy Equation; enthalpy and entropy changes for a perfect gas; relationship between enthalpy and specific heat at constant pressure. Applications of the SFEE to power and refrigeration plant. Introduction to entropy, isentropic efficiency, entropy as a measure of irreversibility, entropy changes in a perfect gas. Property relationships for pure substances, two property rule, phase diagram. T-s, p-h and h-s diagrams. Applications to simple power, refrigeration and heat pump cycles. 2nd law of thermodynamics, Entropy and Clausius inequality, Carnot cycle; corollaries to the 2nd law, absolute temperature scale and thermodynamic efficiency. Mixtures of gases and vapours , introduction to psychrometrics and condensation. Psychrometrics: analysis of air conditioning processes. Vapour power cycles: steam turbine cycles , power cycles and CHP. Refrigeration and heat pump systems; multistage vapour compression cycles, refrigerant properties. Absorption refrigeration: analysis of LiBr systems; comparison with NH3 systems. Compressors: compressor types and applications, analysis and characteristics of compressors, compressors for air conditioning. Fuels and combustion: introduction to fuel types, classification and properties; combustion processes, combustion equations, stoichiometric analysis, combustion efficiency. Dimensionless analysis and similarity : Introduction to the principles of dimensionless analysis; determination of dimensionless groups; use of dimensionless groups in experimental investigation. Turbo-machinery Performance characteristics of rotodynamic machines; centrifugal, axial and mixed flow pumps and fans; use of specific speed for pump selection; simple applications of network machine systems. Euler one dimensional theory for axial and centrifugal turbomachines. Introduction to heat transfer :General conduction equation, 2-D steady state solutions; 1-D unsteady state, lumped parameter approach, Biot and Fourier numbers. Convection : Velocity and temperature boundary layers, calculation of convection coefficients, use of dimensionless parameters in heat transfer, analogies between momentum and heat transfer; dimensionless correlations in forced and natural convection. Radiation : Laws of radiant heat transfer, radiation properties of real materials, geometric factors. Radiation networks in buildings. Extended surfaces : Analysis of heat transfer from fins, overall U-value for extended surfaces. Heat exchangers : Analysis of parallel and counterflow exchangers, log mean temperature difference and Transfer Unit approaches, fouling factors. Heat recovery devices used in buildings. |
![]() |
![]() |
|