Chapter 8: Internal Forced Convection

More documents

Recommendations

Info

• Or∂T1 ∂Qu =−( )∂ x ρcπrdx∂ r2p(8-51)• Since Fourier’s Law ()∂Q ∂ ⎛k(2 πrdx) ∂T ⎞2πkdx ∂ ⎛r∂T⎞= ⎜− ⎟=−⎜ ⎟∂r ∂r⎝ ∂r ⎠ ∂r⎝ ∂r⎠(8-52)Eq 8-51 becomes ( 量 – Energy Equation)u∂T α ∂ ⎛ ∂T ⎞k= ⎜r⎟ ; α =∂x r dr⎝∂r ⎠ ρ cp(8-53)
Constant Surface Heat Flux– Laminar Fully Developed flow• Substituting Eqs. 8-24 and 8-41 into Eq. 8.53u r(8-41)( )⎛= 2Vavg⎜1−⎝rR22⎞⎟⎠∂ T 2q=s = constant∂x ρV c Ravgp(8-24)u∂Tα ∂ ⎛ ∂T⎞= ⎜r⎟∂x r dr⎝∂r⎠(8-53)(8-55)q ⎛ r d dT⎜ ⎞ ⎟ ⎛ ⎜r⎞⎟kR ⎝ R ⎠ r dr ⎝ dr ⎠24s11− =2
Page 1: Chapter 8:Internal Forced Convectio
Page 4 and 5: Average Velocity• The value of th
Page 6 and 7: • For incompressible flow in a ci
Page 8 and 9: The Entrance Region• A fluid ente
Page 10 and 11: Thermal Entrance Region• Consider
Page 12 and 13: • Surface heat flux can be expres
Page 14 and 15: Entry Lengths ()- HydrodynamicLamin
Page 16 and 17: General Thermal Analysis• In the
Page 18 and 19: • In the fully developed region,
Page 20 and 21: Constant Surface Temperature• The
Page 22 and 23: • The temperature difference betw
Page 24 and 25: Laminar Flow in TubesAssumptions:
Page 26 and 27: • Taking the limit as dr, dx 0 g
Page 28 and 29: • Combining the last two equation
Page 30 and 31: • A pressure drop due to viscous
Page 34 and 35: • Separating the variables and in
Page 36 and 37: Constant Surface temperature (circu
Page 38 and 39: - HydrodynamicLaminar flowLh,lamina
Page 40 and 41: Turbulent flow in Tubes• Most cor
Page 42: Moody Diagram

Chapter 8: Internal Forced Convection

Create successful ePaper yourself

Delete template?

Save as template?