INTRODUCTION

1. INTRODUCTION

2. REFERENSI • C.J. GEANKOPLIS : “TRANSPORT PROCESSES AND UNIT OPERATIONS”, EDISI 3, PRENTICE HALL INTERNATIONAL, 1995 • N. de NEVERS : “FLUID MECHANICS FOR CHEMICAL ENGINEERS”, EDISI 2, McGRAW HILL INTERNATIONAL,1991 • R.S. BRODKEY & H.C. HERSHEY: “TRANSPORT PHENOMENA, A UNIFIED APPROACH”, INTERNATIONAL EDITION, McGRAW HILL, 1989 • J.M. WELTY, C.E. WICKS & R.E. WILSON: “FUNDAMENTAL OF MOMENTUM, HEAT, AND MASS TRANSFER”, EDISI 4, JOHN WILEY & SONS, 2001

3. MOMENTUM TRANSFER orFLUID MECHANICS

4. Sir Isaac Newton 1642-1727

5. MECHANICS AND GRAVITATIONAccording to the well-known story, it was on seeing an apple fall in his orchard at some time during 1665 or 1666 that Newton conceived that the same force governed the motion of the Moon and the apple. He calculated the force needed to hold the Moon in its orbit, as compared with the force pulling an object to the ground. He also calculated the centripetal force needed to hold a stone in a sling, and the relation between the length of a pendulum and the time of its swing. These early explorations were not soon exploited by Newton, though he studied astronomy and the problems of planetary motion. Correspondence with Hooke (1679-1680) redirected Newton to the problem of the path of a body subjected to a centrally directed force that varies as the inverse square of the distance; he determined it to be an ellipse, so informing Edmond Halley in August 1684. Halley's interest led Newton to demonstrate the relationship afresh, to compose a brief tract on mechanics, and finally to write the Principia. Book I of the Principia states the foundations of the science of mechanics, developing upon them the mathematics of orbital motion round centres of force. Newton identified gravitation as the fundamental force controlling the motions of the celestial bodies. He never found its cause. To contemporaries who found the idea of attractions across empty space unintelligible, he conceded that they might prove to be caused by the impacts of unseen particles. Book II inaugurates the theory of fluids: Newton solves problems of fluids in movement and of motion through fluids. From the density of air he calculated the speed of sound waves. Book III shows the law of gravitation at work in the universe: Newton demonstrates it from the revolutions of the six known planets, including the Earth, and their satellites. However, he could never quite perfect the difficult theory of the Moon's motion. Comets were shown to obey the same law; in later editions, Newton added conjectures on the possibility of their return. He calculated the relative masses of heavenly bodies from their gravitational forces, and the oblateness of Earth and Jupiter, already observed. He explained tidal ebb and flow and the precession of the equinoxes from the forces exerted by the Sun and Moon. All this was done by exact computation. Newton's work in mechanics was accepted at once in Britain, and universally after half a century. Since then it has been ranked among humanity's greatest achievements in abstract thought. It was extended and perfected by others, notably Pierre Simon de Laplace, without changing its basis and it survived into the late 19th century before it began to show signs of failing. See Quantum Theory; Relativity.

6. TRANSPORT PHENOMENA ? • TRANSPORT PHENOMENA = FENOMENA PERPINDAHAN = PERISTIWA PERPINDAHAN • TRANSPORT PHENOMENA MELIBATKAN 3 (TIGA) PROSES PERPINDAHAN : • PERPINDAHAN MASSA • PERPINDAHAN PANAS • PERPINDAHAN MOMENTUM • PROSES PERPINDAHANNYA SERING TERJADI SECARA SIMULTAN DENGAN ANALOGI SAMA

7. MEKANISME TRANSFER • MEKANISME TRANSFER MOLEKULER (MTM) • MEKANISME TRANSFER TURBULENSI (MTB)

8. BENTUK ANALOGI HEAT TRANSFER FIRE MEKANISME TRANSFER PANAS MOLEKULER HEAT FLOW HK FOURIER Fluks panas J/s.m2 Kons. panas J/m3 Difusivitas panas, m2/s

9. BENTUK ANALOGI MASS TRANSFER N2 O2 MEKANISME TRANSFER MASSA MOLEKULER HUKUM FICK Fluks massa A mol/s.m2 Kons. massa A mol/m3 Difusivitas molekul A dlm B, m2/s

10. Fluks mom arah z akibat komponen kecepatan x (kg.m/s)/s.m2 Difusivitas momentum,  m/r m2/s Arah perpindahan momentum MEKANISME TRANSFER MOMENTUM MOLEKULER BENTUK ANALOGI LAMINAR FLOW z HK NEWTON VISKOSITAS MOMENTUM TRANSFER x

11. MOMENTUM TRANSFER ? MOMENTUM TRANSFER = FLUID MECHANICS MOMENTUM TRANSFER : THE STUDY OF FORCE AND MOTION OF FLUIDS

12. PENTINGNYAMEKANIKA FLUIDA? (1) • PROCESS INDUSTRIES: BEBERAPA MATERIAL ADALAH DALAM BENTUK FLUIDA DAN HARUS DISIMPAN, DIHANDLING, DIPOMPA. • HYDRAULICS: PIPE FLOW, PUMPS, TURBINES • PARTICLE DYNAMICS : FLOW AROUND PARTICLE, INTERACTION OF PARTICLES AND FLUIDS (SETTLING, SLURRIES, PNEUMATIC TRANSPORT, FLUIDIZED BED, AIR POLLUTANT PARTICLE) • MULTIPHASE FLOW: COMBUSTION, SPRAYS, FLOW IN REACTOR, DISTILATION COULOMN

13. PENTINGNYA MEKANIKA FLUIDA?(2) • METEREOLOGY:FLOW OF THE ATMOSPHERE • HYDROLOGY:FLOW WATER IN THE GROUND • VISCOUS FLOWS :LUBRICATION, INJECTION MOLDING, EKSTRUKSI POLIMER, DLL

14. IDE DASAR dalam MEKANIKA FLUIDA (1) • 4 PRINCIPLES: • CONSERVATION OF MASS • CONSERVATION OF ENERGY= FIRST LAW OF THERMO • SECOND NEWTON’S LAW=SECOND LAW THERMO • NEWTON’S LAW OF MOTION • SIMPLE FLOWS : BILA 4 PRINSIP DASAR TERSEBUT DAN SIFAT FISIK TERUKUR DAPAT DISELESAIKAN LANGSUNG SECARA MATEMATIKA GAYA, KECEPATAN, DLL • COMPLEK FLOWS :BILA 4 PRINSIP TERSEBUT HANYA DAPAT DISELESAIKAN DENGAN EKSPERIMEN, ANALISIS DIMENSI & SIMULASI CFD

15. EXAMPLE OF COMPLEX FLOWS ARROUND A SUBMERGED OBJECT

17. EXAMPLE OF COMPLEX FLOWS IN STIRRED TANK ANALYZED BY CFD

18. Fluid velocity vector

19. Solid concentration contour Cav = 20% Cav = 5%

20. 00 10 450 Local gas hold up at several position from baffle

21. EXAMPLE OF COMPLEX FLOWS IN COMBUSTION ANALYZED BY CFD

22. Vektor Kecepatan dalam Ruang Bakar

23. Distribusi Suhu dalam Ruang Bakar

24. Distribusi Suhu dalam Ruang Bakar

25. (a) Distribusi CO2 dalam Ruang Bakar

26. Distribusi O2 dalam Ruang Bakar