HEAT+MASS TRANSFER:FUND.+APPL.
6th Edition
ISBN: 9780073398198
Author: CENGEL
Publisher: RENT MCG
expand_more
expand_more
format_list_bulleted
Videos
Textbook Question
Chapter 6, Problem 33CP
What fluid property is responsible for the development of the velocity boundary layer? For what kinds of fluids will there be no velocity boundary layer on a flat plate?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
A 20degC water flows to 50cmx60cm flat plate with velocity of 6m/s . The flat plate surface temperature is maintained at 40deg C. The water flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, What is the local heat flux (Q/A) at the end of the plate (k=0.86 W/m deg C, Re=3840000, and Pr=0.7)?
Round your answer to 2 decimal places.
Oxygen gas at a temperature of 27°C at atmospheric pressure flows in parallel at 20 m/s over a square thin plate with a side of 10 cm. Since the plate is held at 127°C, what is the heat transfer from the plate to the fluid? Heat transfer (W) takes place from only one surface of the plate
Air is forced to flow over 15 m long flat plate as shown in the following figure with velocity of 9.9
m/s. What is the local forced convection heat transfer coefficient (in W/m2.K) at X= 3.9 m? (For air
use, k= 0.03 W/m.K, Pr= 0.7, v= 1.8 x 10-5 m²/s).
Air
V
X
L= 15 m
Isothermal surface
Chapter 6 Solutions
HEAT+MASS TRANSFER:FUND.+APPL.
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, mechanical-engineering and related others by exploring similar questions and additional content below.Similar questions
- What fluid property is responsible for the development of the velocity boundary layer? What is the effect of the velocity on the thickness of the boundary layer?arrow_forwardA 7 cm diameter bed on a 25 cm long bed, as shown in the figure below. The shaft rotates at 3200 revolutions per minute with uniform intervals of 0.2 mm. Continuous operation The temperatures of the shaft and bearing adjacent to the oil gap are 55 0C. your oil viscosity 0.05 N.s/m2 and its thermal conductivity is 0.17 W/m.K. Continuity, momentum and by simplifying the energy equations and solving for each separately, a) The maximum temperature of the oil, b) Calculate the heat transfer rates to the bearing and shaft.arrow_forward(b) In turbulent flows contrast the approaches that are used to represent the velocity profile within the boundary layer and comment on any limitations that each may offer.arrow_forward
- Air at 10°C and 1 atm is flowing parallel at a velocity of 15.5 m/s over the top flat surface of copper plate. The top surface of the copper plate is 0.03m by 0.03m square. The temperature of copper plate is uniform at 65.6°C. For laminar flow, calculate the dimensionless Reymolds number (Nre) and Nussel number (NNu). Table A.3-3a. Physical Properties of Air at 101.325 kPa (1 Atm Abs), SI Units Bx (Bp²/1?) T (kJ/kg · u x T (Pa ·s, k (W/m 103 (1/K • (°C) T (K) (kg/m³) K) -17.8255.41.379 1.0048 1.62 × 6s or kg/m · s) · K) Npr (1/K) m³) 0.022500.7203.92 2.79 x 108 O 273.21.293 1.0048 1.72 × (0-5 0.024230.7153.65 2.04 × 108 10.0 283.21.246 1.0048 1.78 ×/0 0.024920.7133.53 1.72 x 108 37.8 311.01.137 1.0048 1.90%/0-S 0.027000.7053.22 1.12 x 108 Select one: O A. NRe = 27826.58; NNu =98.58 O B. NRe = 23215.74; NNu =152.68 O C. NRe = 27826.58; NNu = 152.68 O D. NRe = 23215.74; NNu =98.58arrow_forwardTopic: Heat transfer Completely solve and box the final answer. 1. A 20degC water flows to 50cmx60cm flat plate with velocity of 5.2m/s . The flat plate surface temperature is maintained at 40deg C. The air flows parallel to the 50cm side of the plate. If the kinematic viscosity of water is 78x10-8 m2/s, at what length the flow become turbulent?arrow_forwardricant An oil is acting as a lubricant for a pair of cylindrical surfaces such as those shown in 1. The angular velocity of the outer cylinder is 7908 rpmt. The outer cylinder has a radius of 5.06 cm, and the clearance between the cylinders is 0.027 cm. What is the maxi- mum temperature in the oil if both wall temperatures are known to be 158° F? The physical properties of the oil are viscosity density thermal conductivity 92.3 cp 1.22 g cm-3 0.0055 cal sec-1 cm-1 ° C-1arrow_forward
- For fluids with small Prandt number the thermal boundary layer development is much ....................than that of the velocity boundary layer (δt ≫ δ), and it is reasonable to assume ....................... velocity (u = u∞) throughout the thermal boundary layer. Please fill the blankarrow_forwardWrite the importance of dimensional analysis in convection heat transfer.arrow_forwardAir is flowing at a speed of 30 m/sec over a flat plate. The air temperature is 20o C and its pressure is 1 atm. The plate is kept at a constant temperature of 65o C. What is the heat transfer rate per unit length between 7.5 cm to 30 cm, from the edge of the plate?arrow_forward
- 4. During a cold winter day, wind blows parallel to a 4 m high and 10 m long wall of a house. If the air outside is at 5°C and the surface temperature of the wall is 15°C, The general non-dimensional correlation for flow over a flat plate is: Nu =(0.037 Re, 0.8-871) Pr¹/3 where the fluid properties are evaluated at the bulk temperature. If the wind blows at 55 km/h, determine: i. the Reynolds number ii. the convection heat transfer coefficient, and iii. the rate of heat transfer from the wall.arrow_forwardIntroduction to heat convection Solved problems HW-10- 1- Determine the velocity distribution in the velocity boundary layer assuming second degree polynomial: u =C, +C,y+C3y? Answer: The boundary conditions are: du .. u = 0 at y = 0 ; u = u, ; at y = 6 ; = 0 at y = 8 dy и y y This gives: 2.arrow_forwardAn incompressible fluid flows over a flat plate with zero pressure gradient. The boundary layer thickness is 1mm at a location where the Reynolds number is 1000. If the velocity of the fluid alone is increased by a factor of 4, then the boundary layer thickness at the same location, in mm will be 415arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Principles of Heat Transfer (Activate Learning wi...Mechanical EngineeringISBN:9781305387102Author:Kreith, Frank; Manglik, Raj M.Publisher:Cengage Learning
Principles of Heat Transfer (Activate Learning wi...
Mechanical Engineering
ISBN:9781305387102
Author:Kreith, Frank; Manglik, Raj M.
Publisher:Cengage Learning
Ficks First and Second Law for diffusion (mass transport); Author: Taylor Sparks;https://www.youtube.com/watch?v=c3KMpkmZWyo;License: Standard Youtube License