Viscozitatea

Edward J. Shaughnessy Jr&all, Introduction to Fluid Mechanics, Oxford University Press, Fig.1.5, 1.6

Fig. 1.4, White F.M., Fluid Mechanics, Fourth Edition , McGraw Hill

Aderenta fluidelor la suprafete solide Experienta lui Newton

dy

dVAF

Fig. 10-8, Fig. 10-12, Yunus A. Cengel, Introduction to Fluid Mechanics

Viscozitatea dinamica

Variatia viscozitatii dinamice si cinematice a fluidelor cu temperatura

Curbe de curgere

Fluide newtoniene Comparatie fluide newtoniene / fluide nenewtoniene

Fig. 13-3, 13-4, Yunus A. Cengel, Introduction to Fluid Mechanics

Fig.14-3, 14-4, 14-7, Yunus A. Cengel, Introduction to Fluid Mechanics

h

Rezervor colorant

R1 AlimentarePreaplin

Rezervor nivel constant

Robinet reglareTub transparent

masurare

debit

a) curgere laminara

b) tranzitie

c) curgere turbulenta

ν

dv

η

dvρRe

Natura regimului de miscare. Criteriul (Cifra) Reynolds

Comparatie regim laminar/regim turbulent :aspect al miscarii, profil de viteze, calculul vitezei medii vm=v

Fig.14-23, Fig. 14-24, Yunus A. Cengel, Introduction to Fluid Mechanics

Calculul pierderilor de presiune (Δp) resp. a pierderilor de sarcina hL pe o rezistenta liniara

f=λ = coeficientul pierderilor de sarcina liniara

Fig. 14-13, Yunus A. Cengel, Introduction to Fluid Mechanics

Diagramele lui Moody-dependenta coeficientului pierderilor de sarcina liniare functie de cifra Reynolds pt diferite regimuri

de curgere

Fig.14-28, Yunus A. Cengel, Introduction to Fluid Mechanics

Munson &co, Fundamental of Fluid Mechanics

Fig.8.19, Munson &co, Fundamental of Fluid Mechanics

Fig.8.31, Fig.8.32, Tabel 8.2, Munson &co, Fundamental of Fluid Mechanics

Re=2000

Eforturi unitare (tensiuni)

dApFdns

tnsFdFdFd

dA

Fdp s

n

dA

dFσ n

dA

dFτ t

Curgeri exterioare si interioare

Munson &co, Fundamental of Fluid Mechanics

Curgeri interioare – stabilizarea profilului vitezelor

Fig. 8.5 Munson &co, Fundamental of Fluid Mechanics

Fig.14-35, Yunus A. Cengel, Introduction to Fluid Mechanics

Edward J. Shaughnessy Jr&all, Introduction to Fluid Mechanics, Oxford University Press, Fig.3.19, 3.23, 4.22,

Curgeri exterioare

Munson &co, Fundamental of Fluid Mechanics

Forte care actioneaza asupra corpurilor imersate intr-un fluid in miscare

2

2

1vρ

FC D

D

FL (Lift force) = forta ascensionala FD (Drag force)=forta de rezistenta la inaintare CD=coeficientul de rezistenta la inaintare

Fig.15-5, 15-7, Yunus A. Cengel, Introduction to Fluid Mechanics

G.M. Homsy &all, Multimedia Fluid Mechanics, DVD, Cambridge University Press

Strat limita

Fig.9.6, Fig.9.17, Munson &co, Fundamental of Fluid Mechanics

Efectul formei oglinzilor asupra consumului de combustibil

• Cd =1.1

• Cd =0.4

Fig. 15-23, Appl. 15-22, Yunus A. Cengel, Introduction to Fluid Mechanics