Otto-von-Guericke-University Magdeburg Department of Fluid Dynamics and Thermodynamics Professorship Fluid Dynamics
Transcription
Otto-von-Guericke-University Magdeburg Department of Fluid Dynamics and Thermodynamics Professorship Fluid Dynamics
Otto-von-Guericke-University Magdeburg Department of Fluid Dynamics and Thermodynamics Professorship Fluid Dynamics Bernd Wunderlich 2002 (2011) Notes for the Lecture Course in Advanced Fluid Dynamics for the Master Program Chemical and Process Engineering 1. Objectives: • • • • The course will introduce fluid mechanics and establish its relevance in chemical and process engineering. This will help the students from different countries and individual bachelors to reach the same scientific level. Develop the fundamental principles underlying the subject. Demonstrate how these are used for the design of several hydraulic components. Give necessary foundations for the numerical and experimental investigation of flows in apparatusses and devices. 2. Consists of: • Lectures: 14 x 90 min. Classes presenting the concepts, theory and application. Worked examples will also be given to demonstrate how the theory is applied. • Exercises: 7 x 90 min. Further examples are presented to deepen the knowledge. You will be asked to do some calculations - so bring a calculator. Multimedia sessions are included. The course time is not strongly splitted into lectures and exercises time-wise. Therefore, it is possible to put a question during the lecture time also. • Homework: Example problems will be given for each section of the course. Doing these will greatly improve your exam mark. They are course work but do not have credits toward the module. Assessment: 1 written examination of 120 min 3. Specific Elements: • • • • • • • • Introduction – fluid mechanics, fluid and flow properties • fluids vs. solids • Newton’s law of viscosity • thermodynamical and chemical properties • boundary layers • laminar and turbulent flow Forces in static fluids • hydrostatic pressure • Pasqual’s law • Archimedes principle • Manometry / pressure measurement • Fluids in rigid body motion Kinematics • Eulerian and Lagrangian consideration • fluid elements • definitions • dimensionality of a flow field • potential flows Dynamics • The continuity equation. • The Bernoulli equation. • Applications of the Bernoulli equation. • The momentum equation. • Applications of the momentum equation. Real Fluids • Navier-Stokes equations • Laminar flow in pipes and channels. • Reynolds Equation • Bernoulli equation with losses Flow of compressible fluids in conduits • The continuity equation and the energy equation for isotropic flows. • Equations of state • The critical state • Subsonic flows • Shock waves Introduction to dimensional analysis • Dimensional analysis • Similarity Pumps in chemical devices • Division of pump types • Interaction of pumps and chemistry plants • Head against capacity curves • Affinity laws • Operating in parallel and series • Calculation of centrifugal pumps • Positive displacement pumps 4. Books: Any of the book listed below are more than adequate for this module. [1] [2] [3] [4] [5] [6] [7] 5. Fundamentals of Fluid Mechanics, Munson B.R., Okiishi T.H. Introduction to Fluid Mechanics, Fay J.A. Fluid Flow for Chemical Engineers, Holland F.A., Bragg R. Mechanics of Fluids, Massey B S., Van Nostrand Reinhold. Fluid Mechanics, Douglas J F, Gasiorek J M, and Swaffield J A, Longman. Theoretical and Computational Fluid Dynamics, Pozrikidis, C.,Oxford Univ. Press. Handbook of Chemistry and Physics, 69 th Ed., CRC Press, 1988 Other Teaching Resources. [8] http://mathworld.wolfram.com A script of the lecture can be downloaded from the website: http://www.uni-magdeburg.de/isut/master/afd.html password: 4002dfa It contains all figures and equations presented in the lecture. 6. Why we are studying fluid mechanics on a Process and Systems Engineering course? Fluid mechanics is involved in nearly all areas of chemical plants either directly or indirectly. All heat and material transports are based on the flow behavior of liquids, gases and mixtures. Pumps and compressors are needed to realize the desirable processes. 7. System of units To avoid any confusion on this course we will always use the SI (metric) system - which you will already be familiar with. It is essential that all quantities be expressed in the same system or the wrong solution will results. 8. The SI System of units The SI system consists of six primary units, from which all quantities may be described. For convenience secondary units are used in general practise which are made from combinations of these primary units. Primary Units The six primary units of the SI system are shown in the table below: Quantity SI Unit Dimension length meter, m L mass kilogram, kg M time second, s T temperature Kelvin, K Θ current ampere, A I luminosity candela Cd Derived Units Quantity velocity acceleration SI Unit m/s m/s2 N force kg m/s2 Joule J energy (or work) N m, kg m2/s2 Watt W power N m/s kg m2/s3 Pascal P, pressure N/m2, ( or stress) kg/m/s2 density kg/m3 N/m3 specific weight kg/m2/s2 N s/m2 viscosity kg/m s N/m surface tension kg /s2 Dimension ms-1 ms-2 LT-1 LT-2 kg ms-2 M LT-2 kg m2s-2 ML2T-2 Nms-1 kg m2s-3 ML2T-3 Nm-2 kg m-1s-2 ML-1T-2 kg m-3 ML-3 kg m-2s-2 ML-2T-2 N sm-2 kg m-1s-1 Nm-1 kg s-2 M L-1T-1 MT-2