Fundamentals of Heat and Mass Transfer
7th Edition
ISBN: 9780470917855
Author: Bergman, Theodore L./
Publisher: John Wiley & Sons Inc
expand_more
expand_more
format_list_bulleted
Question
Chapter 7, Problem 7.149P
To determine
The average drying rate of the paper per unit surface area.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Consider two cases involving parallel flow of dry air at V = 4.5 m/s, T, = 45°C, and atmospheric pressure over an isothermal plate at
T = 20°C. In the first case, Re= 5x 105, while in the second case the flow is tripped to a turbulent state atx = 0 m. At whatx
-location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m?, at this
location for the two cases?
x =
i
m
Jam
i
W/m?
i
W/m?
I turb
Consider two cases involving parallel flow of dry air at V = 5 m/s, T = 45°C, and atmospheric pressure over an isothermal plate
at T = 20°C. In the first case, Rex, = 5 x 105, while in the second case the flow is tripped to a turbulent state at x = 0 m. At what
x-location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this
location for the two cases?
x =
d'am
=
qturb =
Mc
i
m
W/m²
W/m²
Consider two cases involving parallel flow of dry air at V = 1.5 m/s, T=45°C, and atmospheric pressure over an isothermal plate at
T = 20°C. In the first case, Rex, = 5 x 105, while in the second case the flow is tripped to a turbulent state at x = 0 m. At what x
-location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this
location for the two cases?
x =
9jam
9 turb
II
=
i
i
m
W/m²
W/m²
Chapter 7 Solutions
Fundamentals of Heat and Mass Transfer
Ch. 7 - Consider the following fluids at a film...Ch. 7 - Engine oil at 100C and a velocity of 0.1 m/s flows...Ch. 7 - Consider steady, parallel flow of atmospheric air...Ch. 7 - Consider a liquid metal (Pr1), with free stream...Ch. 7 - Consider the velocity boundary layer profile for...Ch. 7 - Consider a steady, turbulent boundary layer on and...Ch. 7 - Consider flow over a flat plate for which it is...Ch. 7 - A flat plate of width 1 m is maintained at a...Ch. 7 - An electric air heater consists of a horizontal...Ch. 7 - Consider atmospheric air at 25C and a velocity of...
Ch. 7 - Repeat Problem 7.11 for the case when the boundary...Ch. 7 - Consider water at 27°C in parallel flow over an...Ch. 7 - Explain under what conditions the total rate of...Ch. 7 - In fuel cell stacks, it is desirable to operate...Ch. 7 - The roof of a refrigerated truck compartment is of...Ch. 7 - The top surface of a heated compartment consists...Ch. 7 - Calculate the value of the average heat transfer...Ch. 7 - The proposed design for an anemometer to determine...Ch. 7 - Steel (AISI 1010) plates of thickness =6mm and...Ch. 7 - Consider a rectangular fin that is used to cool a...Ch. 7 - The Weather Channel reports that it is a hot,...Ch. 7 - In the production of sheet metals or plastics, it...Ch. 7 - An array of electronic chips is mounted within a...Ch. 7 - A steel strip emerges from the hot roll section of...Ch. 7 - In Problem 7.23. an anemometer design was...Ch. 7 - One hundred electrical components, each...Ch. 7 - The boundary layer associated with parallel flow...Ch. 7 - Forced air at 250C and 10 m/s is used to cool...Ch. 7 - Air at atmospheric pressure and a temperature of...Ch. 7 - Consider a thin, 50mm50mm fuel cell similar to...Ch. 7 - The cover plate of a flat-plate solar collector is...Ch. 7 - An array of 10 silicon chips, each of length...Ch. 7 - A square (10mm10mm) silicon chip is insulated on...Ch. 7 - A circular pipe of 25-mm outside diameter is...Ch. 7 - An L=1-m- long vertical copper tube of inner...Ch. 7 - A long, cylindrical, electrical heating element of...Ch. 7 - Consider the conditions of Problem 7.49, but now...Ch. 7 - Pin fins are to be specified for use in an...Ch. 7 - Prob. 7.52PCh. 7 - Prob. 7.53PCh. 7 - Hot water at 500C is routed from one building in...Ch. 7 - In a manufacturing process, long aluminum rods of...Ch. 7 - Prob. 7.58PCh. 7 - To determine air velocity changes, it is proposed...Ch. 7 - Determine the convection heat loss from both the...Ch. 7 - Prob. 7.63PCh. 7 - Prob. 7.64PCh. 7 - Prob. 7.67PCh. 7 - A thermocouple is inserted into a hot air duct to...Ch. 7 - Consider a sphere with a diameter of 20 mm and a...Ch. 7 - Prob. 7.76PCh. 7 - A spherical, underwater instrument pod used to...Ch. 7 - Worldwide. over a billion solder balls must be...Ch. 7 - Prob. 7.80PCh. 7 - Prob. 7.81PCh. 7 - Consider the plasma spray coating process of...Ch. 7 - Prob. 7.83PCh. 7 - Tissue engineering involves the development of...Ch. 7 - Consider temperature measurement in a gas stream...Ch. 7 - Prob. 7.89PCh. 7 - A preheater involves the use of condensing steam...Ch. 7 - Prob. 7.91PCh. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - A tube bank uses an aligned arrangement of...Ch. 7 - Repeat Problem 7.94, but with NL=7,NT=10, and...Ch. 7 - Heating and cooling with miniature impinging jets...Ch. 7 - A circular transistor of 10-mm diameter is cooled...Ch. 7 - A long rectangular plate of AISI 304 stainless...Ch. 7 - A cryogenic probe is used to treat cancerous skin...Ch. 7 - Prob. 7.103PCh. 7 - Prob. 7.104PCh. 7 - Prob. 7.105PCh. 7 - Consider the packed bed of aluminum spheres...Ch. 7 - Prob. 7.108PCh. 7 - Prob. 7.109PCh. 7 - Prob. 7.111PCh. 7 - Packed beds of spherical panicles can be sintered...Ch. 7 - Prob. 7.114PCh. 7 - Prob. 7.116PCh. 7 - Prob. 7.117PCh. 7 - Prob. 7.118PCh. 7 - Prob. 7.119PCh. 7 - Prob. 7.120PCh. 7 - Dry air at 35°C and a velocity of 20 m/s flows...Ch. 7 - Prob. 7.123PCh. 7 - Benzene, a known carcinogen, has been spilled on...Ch. 7 - Prob. 7.125PCh. 7 - Prob. 7.126PCh. 7 - Condenser cooling water for a power plant is...Ch. 7 - Prob. 7.128PCh. 7 - In a paper-drying process, the paper moves on a...Ch. 7 - Prob. 7.131PCh. 7 - Prob. 7.132PCh. 7 - Prob. 7.133PCh. 7 - Prob. 7.134PCh. 7 - Prob. 7.136PCh. 7 - It has been suggested that heat transfer from a...Ch. 7 - Prob. 7.138PCh. 7 - Cylindrical dry-bulb and wet-bulb thermometers are...Ch. 7 - The thermal pollution problem is associated with...Ch. 7 - Cranberries are harvested by flooding the bogs in...Ch. 7 - A spherical drop of water, 0.5 mm in diameter, is...Ch. 7 - Prob. 7.143PCh. 7 - Prob. 7.144PCh. 7 - Prob. 7.145PCh. 7 - Prob. 7.146PCh. 7 - Prob. 7.147PCh. 7 - Consider an air-conditioning system composed of a...Ch. 7 - Prob. 7.149P
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
- Air at 22˚C and at atmospheric pressure flows over a flat plate at a velocity of 1.65 m/s. If the length of the plate is 2.179 m and its temperature is 98 ˚C, Calculate Heat rate by using exact and approximate methods both. What is the %age difference of the heat transfer rate values by these methods? Take width of the plate as unity. Properties given at 60˚C are as follows: Density: 1.058 kg/m3 , cp = 1.005 kJ/kg˚C, k= 0.02897 w/m˚C, Kinematic viscosity is 18.97 × 10-6 m2 /sarrow_forwardA vehicle carrying refrigeration box is moving with a speed of 24 m/s on a road withambient temperature of 323 K. The dimensions of box are 3 m(H) × 4 m (W) × 10 m (L).Assume a wall temperature of 283 K and air flow is parallel to the longest side of the box.Neglecting the heat loss from the front side and backside of the box, calculate heat lossfrom four surfaces. For flow over flat surfaces useNu = 0.036(Re)0.8(Pr)1/3The properties of air at bulk mean temperature are : = 1.165 kg/m3, Pr = 0.701, cp = 1005 J/kg – K, = 16 × 10–6m2/sarrow_forwardRequired information Water at 20°C is flowing with velocity of 0.89 m/s between two parallel flat plates placed 1 cm apart. Given: The properties of water at 20°C are p= 998.0 kg/m3, µ = 1.002 x 103 kg/m-s and Pr = 7.01 Determine/the distance from the entrance at which the velocity boundary layers meet. (Round the final answer to one decimal place.) The distance from the entrance at which the velocity boundary layers meet is m.arrow_forward
- Consider two cases involving parallel flow of dry air at V = 3.5 m/s, T = 45°C, and atmospheric pressure over an isothermal plate at T = 20°C. In the first case, Rex.c = 5 × 105, while in the second case the flow is tripped to a turbulent state at x = 0m. At what x -location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m², at this location for the two cases? x = 9'1'am 9 turb = = i i i m W/m² W/m²arrow_forwardConsider two cases involving the parallel flow of dry air at V= 1.5 m/s, T∞=45°C, and atmospheric pressure over an isothermal plate at Ts=20°C. In the first case, Rex,c=R5 × 105, while in the second case the flow is tripped to a turbulent state at x=0 m. At what x‐location, in m, are the thermal boundary layer thicknesses of the two cases equal? What are the local heat fluxes, in W/m2, at this location for the two cases?arrow_forward8. A lead pipe has 2 cm inside diameter, 3 cm outer diameter, length of 130 cm. Liquid water at 4°C flows through the pipe with a bulk velocity of 0.03 km/hr. Air is blown around the outside of the pipe at 20 deg C. The inside wall of the said pipe has a temperature of 8 deg Celsius. Density of liquid water= 1000 kg/m³ Cp water=4.210 J/kgK Viscosity of liquid water= 1.5674 x10° Pa.s thermal conductivity of lead = 35 W/mK thermal conductivity of water = 0.575 W/mK Find: Overall heat coefficient (U) based on outside surface area b. System's heat transfer rate Prandtl (Pr), Reynolds (Re) numbers and type of flow а. с.arrow_forward
- Atmospheric air at 5°C enters a thin walled 12cm diameter 20m long isothermal pipe (Ts=constant) at a velocity of 2.5m/s and leaves at 19°C. Estimate the surface temperature Ts.arrow_forwardWater at 45.0oC flows over a large plate at a velocity of 30.0 cm/s. The plate is 1.0 m long (in the flow direction), and its surface is maintained at a uniform temperature of 5.0oC. Calculate the steady rate of heat transfer per unit width of the plate. Properties The properties of air at 1 atm and the film temperature of (Ts+T∞)/2 = (5+45)/2 = 25°C are: ρ = 996.6 kg/m3, k = 0.610 W/m.oC, μ = 0.854x10-3 kg/m.s, Pr = 5.85arrow_forwardA plane-inclined pad thrust bearing is 160mm wide and 40mm long in the direction of sliding. The sliding velocity is 6 m/s and the bearing is supported so that the inlet film thickness is always three times the outlet film thickness. A load 18 kN is carried by the bearing and Tellus 37 oil is supplied at an inlet temperature of 40̊ C. Assuming that 80% of the heat generated in the bearing is carried away by the oil, describe the operating characteristics of the bearing (Pm, Q, F, tm,). Density is 875 kg/m3 and specific heat is Cp=1.880 J/g-K.arrow_forward
- Merrill et al. (1965) in a series of classic experiments studied the flow of blood in capillary tubes of various diameters. The blood had a hematocrit of 39.3 and the temperature was 20°C. They measured the pressure drop as a function of the flow rate for five tube diameters ranging from 288 to 850 μm. When they expressed the measured pressure drops in terms of the wall shear stress, and the volumetric flow rates in terms of the reduced average velocity, all of the data for the various tube sizes formed, within the experimental accuracy, a single line as predicted by the Rabinowitsch equation expressed in terms of reduced average velocity. From their results they provide the following values of the Casson parameters at 20°C: τy = 0.0289 dynes cm−2 and s = 0.229 (dynes s cm−2)1/2. Using these values for τy and s, show that the equation below for reduced average velocity provides an excellent fit to their data summarized in the following table. (Wall shear stress) τw , dynes cm-2…arrow_forwardHeat transfers Water (T= 10 C, , k=0.644 W/m.C, υ = 5.54× 10^-7 m2/s, Pr=3.55), flow over plate 1m x 1m , with velocity 2 m/s. the plate surface temperature is 90 C. Give the answer for the following: Nu number equal to Total heat transfer The flow type The average heat transfer coefficientarrow_forwardProvide schematic diagram and solutions.arrow_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
Intro to Compressible Flows — Lesson 1; Author: Ansys Learning;https://www.youtube.com/watch?v=OgR6j8TzA5Y;License: Standard Youtube License