Thermodynamics Chapter 8

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AKISKANLAR MEKANIGI

• Kaynak Kitap

AKISKANLAR MEKANIGI Y.A. ÇENGEL, JM.
CIMBALA (Türkçesi PALME YAYINCILIK
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AKISKANLAR MEKANIGININ ILGI ALANLARI

• Bir akiskan içerisinde faaliyet gösteren ve
  içerisinde akiskan faaliyeti olan bütün sistemler
  akiskanlar mekaniginin ugras alanina girer.

• Uçaklar, hava araçlari, jet motorlari, pervaneler

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AKISKANLAR MEKANIGININ UGRAS ALANI
Pompalar
Deniz araçlari
Kan dolasim ve bosaltim sistemleri
(BIOAKISKANLAR MEKANIGI)
Türbinler
Otomobiller
Fanlar
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AKISKAN ÖZELLIKLERI
FIZIKSEL ÖZELLIKLER
KINEMATIK ÖZELLIKLER
TERMODINAMIK ÖZELLIKLERI

• Kütle
• Hacim

• Hiz
• Ivme
• Açisal hiz
• Yer degistirme vektörü
• Hacimsel debi
• Hacimsel büyüme hizi

• Basinç
• Yogunluk
• Sicaklik
• Iç enerji
• Entalpi
• Entropi
• Özgül isilar
• Dinamik vizkozite
• Isil iletkenlik

AKIS ÖZELLIKLERI

• Newton tipi (Dogrusal degisime uyan)
• Newton tipi olmayan (Dogrusal degisime uymayan )

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YÜZEY GERILME
Yüzey gerilimi,
Sivinin yüzeyindeki herhangi bir dogrunun birim
uzunluguna, dik dogrultuda etki eden kuvvettir.
Böceklerin su yüzeyinde yürümesi
Iç Çekim Akiskanini moleküller arasindaki içi
çekim kuvveti (KOHEZYON) Dis Çekim Akiskanla
digr akiskan veya kati cisim arasindaki çekim
kuvveti (KOHEZYON)
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Hafif metalin su yüzeyinde durmasi
Yaprak üzerinde damlalar
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Motivasyon

• Akiskanlar Mekanigi Uygulamalri
• Aerodinamik (Aerodynamics)
• Biyomühendislik ve biyolojik sistemler(Bioengineer
  ing and biological systems)
• Yanma (Combustion)
• Enerji üretimi (Energy generation)
• Geoloji(Geology)
• Hidrolik ve Hidroloji(Hydraulics and Hydrology)
• Hidrodinamik(Hydrodynamics)
• Meteoroloji(Meteorology)
• Okyanus ve Okyanuz Mühendisligi (Ocean and
  Coastal Engineering)
• Su kaynaklari(Water Resources)
• Çok sayida diger örnekler (numerous other
  examples)
• Akiskanlar mekanigi güzeldir (Fluid Mechanics is
  beautiful)

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Aerodynamics
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Bioengineering
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Energy generation
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Geology
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River Hydraulics
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Hydraulic Structures
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Hydrodynamics
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Meteorology
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Water Resources
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Fluid Mechanics is Beautiful
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Tsunamis

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Tsunamis

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Tsunamis

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Methods for Solving Fluid Dynamics Problems

• Analytical Fluid Dynamics (AFD) Mathematical
  analysis of governing equations, including exact
  and approximate solutions. This is the primary
  focus of ME33
• Computational Fluid Dynamics (CFD) Numerical
  solution of the governing equations
• Experimental Fluid Dynamics (EFD) Observation and
  data acquisition.

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Analytical Fluid Dynamics

• How fast do tsunamis travel in the deep ocean?
• Incompressible Navier-Stokes equations
• Linearized wave equation for inviscid,
  irrotational flow
• Shallow-water approximation, l/h gtgt 1
• For g 32.2 ft/s2 and h10000 ft, c567 ft/s
  387 miles/hr

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Computational Fluid Dynamics

• In comparison to analytical methods, which are
  good for providing solutions for simple
  geometries or behavior for limiting conditions
  (such as linearized shallow water waves), CFD
  provides a tool for solving problems with
  nonlinear physics and complex geometry.

Animation by Vasily V. Titov, Tsunami Inundation
Mapping Efforts, NOAA/PMEL
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Experimental Fluid Dynamics

• Oregon State University Wave Research Laboratory
• Model-scale experimental facilities
• Tsunami Wave Basin
• Large Wave Flume
• Dimensional analysis (Chapter 7 of CC) is very
  important in designing a model experiment which
  represents physics of actual problem

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Experimental Fluid Dynamics

• Experiments are sometimes conducted in the field
  or at full scale
• For tsunamis, data acquisition is used for
  warning
• DART Deep-ocean Assessment and Reporting of
  Tsunamis
• Primary sensor Bourdon tube for measuring
  hydrostatic pressure

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M1 tank part load performance

• Power plant AGT-1500 Turbine, 1500hp
• Performance   Maximum speed gt 70 km/h
• 1 efficiency at idle!!!!
• High power-to-weight ratio
• Use CODOG for extended range
• LV100-5 gas turbine engine for the M1A2. The new
  engine is lighter and smaller with rapid
  acceleration, quieter running and no visible
  exhaust.

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Turboprop the PT6Pratt Whitney Canada
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Turbofan engine
Fan diameter 2.95 meters
Power A380 maiden flight
Thrust 338kN (Trent 977)
Civil turbofan (high bpr)
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Turbofan engine
RM12 engine powering the Swedish GRIPEN fighter
Military turbofan (low bpr)