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MODULE DESCRIPTOR MECH2004 – Mechanics of Fluids and Thermodynamics Code: Title: Level: UCL Credits/ECTs: Start: End: Taught by: MECH2004 Mechanics of Fluids and Thermodynamics 2 0.5/7.5 September June Dr Suen (50%) Module Coordinator Dr Aleiferis (50%) Prerequisites Completion of first year Thermodynamics and Mechanics of Fluids. Mathematics to first year undergraduate level including integrals and differential equations. Course Aims The aim of the fluids part of the course is to study the basics of fluid flow through pipes and around bodies. To achieve this it is necessary to study the boundary layer in some detail, what it is, how it can be modelled, how it behaves, how it can be controlled and the consequences this has on fluid flow and engineering design features. Analysis includes definition and use of coefficients of friction, pressure, drag and lift. The fundamentals of fluids mechanics and aerodynamics/hydrodynamics are studied both via empirical formulas and by introduction and derivation of differential equations from first principles. Analysis is carried out holistically in the context of experimental observations as well as theoretical modelling for various applications. The thermodynamics part of the course covers 4 main topics: mixtures of ideal gases, elementary combustion, steam turbine and gas turbine cycles. The coverage starts with a brief summary/revision of ideal gas law. The concept of ideal gas mixture and the calculation of its properties will be introduced. In particular, the mixture of air and water vapour will be studied. Various terminologies for moist air and their applications in air-conditioning will be addressed. Finally a direct-contact device, i.e. cooling tower will be studied including its operation, advantages and disadvantage. For combustion, students will learn how to balance a combustion equation for a given fuel and determine the corresponding stoichiometric coefficients and air/fuel ratio, and how to perform molar and gravimetric (wet and dry) analysis of the composition of the combustion product. For steam and gas turbine cycles, basic system components/configurations and operation (Rankine cycle and air-standard Joule cycle), and how the component/system performance is defined, will be introduced. The course provides students with a good basic understanding of factors affecting system performance and the techniques for improving the performance. Students will also have opportunities to practice on cycle calculations involving correct implementation of the energy and mass balances around the system, and the use of Steam Tables (SI Units). Method of Instruction Lecture presentations, tutorial classes and (two) laboratory classes. Assessment The course has the following assessment components: Written Examination (3 hours, 75%) Two Laboratories (25%) one for Mechanics of Fluids (TF1) and one for Applied Thermodynamics (TF2) To pass this course, students must: Obtain an overall pass mark of 40% for all sections combined The examination rubric is: Answer FIVE questions (from eight offered) and answer no more than THREE questions from EITHER section (A or B). All questions carry equal weight. Resources: Page | 1 Massey, B.S. (revised by J. Ward-Smith), Mechanics of Fluids, 8th Edition, Taylor and Francis, 2007. White, F.M., Fluid Mechanics, 6th Edition, McGraw-Hill, 2006. Turns S R, Thermal-Fluid Science, An Integrated Approach, Cambridge University Press, 2006. Cengel Y A and Boles M A, Thermodynamics, An Engineering Approach, McGraw Hill, 2006. Additional Information None Content Fluid Mechanics Approximately 15 hours of lectures and 8 tutorial sessions. 1 laboratory class on pipe flows. 1. Introduction Overview and introduction to the course Introduction to Boundary Layers 2. Flow in Pipes Entrance length and velocity profile for laminar and turbulent conditions Flow in rough pipes and application of the Moody diagram 3. Flow Past a Body Drag and friction Inviscid flow theory and experimental data Bluff bodies and aero/hydro-foils Effects of pressure gradient on boundary layers and methods for control 4. The Momentum Integral Equation Definition of displacement thickness, momentum thickness and shape parameter Derivation of MIE for 2-D flow over a solid plate Application for laminar and turbulent boundary layer on a plate 5. The Navier-Stokes Equations Derivation of the Navier-Stokes Equations Simplifications Prandtl’s Hypothesis The Boundary Layer Equations Thermodynamics Approximately 16 lectures and 12 tutorial/revision sessions. 1 laboratory session on IC Engine. 1. Mixtures of ideal gases Overview and introduction to the course Revision on the Ideal Gas Law and compressibility factor Gibbs-Dalton Law and properties of ideal gas mixtures Mixtures of ideal gases and vapour Basic psychrometric processes and air-conditioning Cooling tower Numerical Examples 2. Elementary combustion Combustion equations and conservation of mass Stoichiometric coefficients and mixtures Stoichiometric A/F ratio; weak and rich mixtures Wet and dry analysis of combustion product Numerical examples 3. Steam turbine cycles Introduction to basic steam turbine cycle and associated components Comparison between Carnot and Rankine cycles; effects of work ratio on cycle efficiency Introduction to mean temperature of heat reception and rejection Methods for improving cycle efficiency: Reheat cycle and feed heating Closed-type and open-type feed water heaters Numerical examples Page | 2 4. Gas turbine cycles Introduction to basic gas turbine cycle and associated components Closed and open circuit gas cycles Basic cycle calculations; isentropic efficiency for gas compressor and turbine; work ratio Parameters affecting the specific work and efficiency of the air-standard Joule cycle Specific fuel consumption Numerical examples General Learning Outcomes Knowledge and understanding A broad range of the basic principles of fluid mechanics associated with the analysis of flow in pipes and around bodies; an introduction to the Momentum Integral and Navier-Stokes equations. Energy balance in gas and steam cycles; psychometric analysis of basic air conditioning systems; elementary combustion theory Skills (i) Intellectual Fluid mechanics principles applied to flow past bodies, also compressible and incompressible flows; the application of this analysis to a range of engineering systems. Performance improvement of thermal power plant; design/sizing of components in air conditioning systems; determination of stoichiometric, weak and rich air fuel ratio. (ii) Practical Common laboratory test and measurement equipment for boundary layer study; power measurement and combustion analysis of IC engine; collection and analysis of data in the context of the theory. (iii) Transferable Generate and systematically analyse a wide range of simple fluid flow and thermodynamic problems and devices of practical engineering significance. Page | 3