HEAT+MASS TRANSFER-PHYSICAL ACCESS CODE
6th Edition
ISBN: 9781265896676
Author: CENGEL
Publisher: MCG CUSTOM
expand_more
expand_more
format_list_bulleted
Concept explainers
Question
Chapter 3, Problem 231P
To determine
To find:Rate of heat loss through the ceiling.
Expert Solution & Answer

Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
please solve it with Pa and mm, thank you!
Can you help me by providing the solutions in MATLAB code?
Can you use MATLAB to help me solve part (d)
Chapter 3 Solutions
HEAT+MASS TRANSFER-PHYSICAL ACCESS CODE
Ch. 3 - Consider heat conduction through a wall of...Ch. 3 - Consider heat conduction through a plane wall....Ch. 3 - What does the thermal resistance of a medium...Ch. 3 - Can we defme the convection resistance for a unit...Ch. 3 - Consider steady heat transfer through the wall of...Ch. 3 - How is the combined heat transfer coefficient...Ch. 3 - Why are the convection and the radiation...Ch. 3 - Consider steady one-dimensional heat transfer...Ch. 3 - Someone comments that a microwave oven can be...Ch. 3 - Consider two cold canned drinks, one wrapped in a...
Ch. 3 - The bottom of a pan is made of a 4-mm-thick...Ch. 3 - Consider a surface of area A at which the...Ch. 3 - How does the thermal resistance network associated...Ch. 3 - Consider steady one-dimensional heat transfer...Ch. 3 - Consider a window glass consisting of two...Ch. 3 - Prob. 16PCh. 3 - Consider a person standing in a room at 20C with...Ch. 3 - Consider an electrically heated brick house...Ch. 3 - A12-cm18-cm circuit board houses on its surface...Ch. 3 - Water is boiling in a 25-cm-diameter aluminum pan...Ch. 3 - A cylindrical resistor element on a circuit board...Ch. 3 - Prob. 22PCh. 3 - A1.0m1.5m double-pane window consists of two...Ch. 3 - Prob. 24PCh. 3 - Prob. 25PCh. 3 - Prob. 26PCh. 3 - Prob. 27PCh. 3 - Prob. 28EPCh. 3 - To defog the rear window of an automobile, a very...Ch. 3 - A transparent film is to be bonded onto the top...Ch. 3 - To defrost ice accumulated on the outer surface of...Ch. 3 - Prob. 32PCh. 3 - Prob. 33PCh. 3 - Prob. 34PCh. 3 - Prob. 35PCh. 3 - Heat is to be conducted along a circuit board that...Ch. 3 - Prob. 37EPCh. 3 - Consider a house that has a 10m20-m base and a...Ch. 3 - Prob. 39EPCh. 3 - Prob. 40PCh. 3 - Prob. 41PCh. 3 - Prob. 42PCh. 3 - Prob. 43PCh. 3 - What is thermal contact resistance? How is it...Ch. 3 - Will the thermal contact resistance be greater for...Ch. 3 - Explain how the thermal contact resistance can be...Ch. 3 - A waII consists of two layers of insulation...Ch. 3 - Prob. 48CPCh. 3 - Consider two surfaces pressed against each other....Ch. 3 - Prob. 50PCh. 3 - Two 5-cm-diameter, 15-cm-long aluminum bars...Ch. 3 - Prob. 52PCh. 3 - Two identical aluminum plates with thickness of 30...Ch. 3 - A tvolayer wall is made of two metal plates, with...Ch. 3 - Prob. 55PCh. 3 - An aluminum plate and a stainless steel plate are...Ch. 3 - Prob. 57PCh. 3 - Prob. 58PCh. 3 - Prob. 59PCh. 3 - Prob. 60PCh. 3 - Prob. 61PCh. 3 - What are the two approaches used in the...Ch. 3 - The thermal resistance networks can also be used...Ch. 3 - When plotting the thermal resistance network...Ch. 3 - A 10-cm-thick vall is to be constructed with...Ch. 3 - Prob. 66EPCh. 3 - Prob. 67PCh. 3 - Prob. 68PCh. 3 - Prob. 69PCh. 3 - Prob. 70PCh. 3 - Prob. 71PCh. 3 - Prob. 72PCh. 3 - A 12-m-long and 5-m-high wall is constructed of...Ch. 3 - Prob. 74EPCh. 3 - Prob. 75PCh. 3 - Prob. 76PCh. 3 - Prob. 77PCh. 3 - What is an infinitely long cylinder? When is it...Ch. 3 - Can the thermal resistance concept be used for a...Ch. 3 - Consider a short cylinder whose top and bottom...Ch. 3 - Prob. 81PCh. 3 - Prob. 82PCh. 3 - Prob. 83PCh. 3 - Superheated steam at an average temperature 20C is...Ch. 3 - Prob. 85PCh. 3 - Prob. 86PCh. 3 - Prob. 87EPCh. 3 - Prob. 88EPCh. 3 - Prob. 89EPCh. 3 - Prob. 90PCh. 3 - Prob. 91PCh. 3 - Prob. 92PCh. 3 - Prob. 93EPCh. 3 - Prob. 94PCh. 3 - Prob. 95PCh. 3 - Prob. 96PCh. 3 - Liquid hydrogen is flowing through an insulated...Ch. 3 - Exposure to high concentrations of gaseous ammonia...Ch. 3 - A mixture of chemicals is flowing in a pipe...Ch. 3 - Ice slurry is being transported in a pipe...Ch. 3 - Prob. 101PCh. 3 - Prob. 102PCh. 3 - Prob. 103PCh. 3 - What is the critical radius of insulation? How is...Ch. 3 - Prob. 105CPCh. 3 - Prob. 106CPCh. 3 - Prob. 107CPCh. 3 - A pipe is insulated such that the outer radius of...Ch. 3 - A 0.083-in-diameter electrical wire at 90F is...Ch. 3 - Repeat Prob. 3-109E, assuming a thermal contact...Ch. 3 - Prob. 111PCh. 3 - Prob. 112PCh. 3 - Hot air is to be cooled as it is forced to flow...Ch. 3 - Prob. 114CPCh. 3 - Prob. 115CPCh. 3 - The fins attached to a surface are determined to...Ch. 3 - Explain how the fins enhance heat transfer from a...Ch. 3 - How does the overall effectiveness of a finned...Ch. 3 - Hot water is to be cooled as it flows through the...Ch. 3 - Consider two finned surfaces that are identical...Ch. 3 - The heat transfer surface area of a fin is equal...Ch. 3 - Does the (a) efficiency and (b) effectiveness of a...Ch. 3 - Two pin fins are identical, except that the...Ch. 3 - Two plate fins of constant rectangular cross...Ch. 3 - Two finned surfaces are identical, except that the...Ch. 3 - Obtain a relation for the fin efficiency for a fin...Ch. 3 - Prob. 127PCh. 3 - Consider a very long rectangular fin attached to a...Ch. 3 - Prob. 129PCh. 3 - Prob. 130PCh. 3 - Prob. 131PCh. 3 - Prob. 132PCh. 3 - Prob. 133EPCh. 3 - Prob. 134EPCh. 3 - Prob. 135PCh. 3 - Prob. 136PCh. 3 - Prob. 137PCh. 3 - Prob. 138PCh. 3 - Prob. 139PCh. 3 - Prob. 140PCh. 3 - Prob. 141PCh. 3 - Prob. 142PCh. 3 - Prob. 143PCh. 3 - Prob. 144PCh. 3 - Prob. 145PCh. 3 - Prob. 146PCh. 3 - The human body is adaptable to extreme climatic...Ch. 3 - Consider the conditions of Example 3-14 in the...Ch. 3 - Consider the conditions of Example 3-14 in the...Ch. 3 - Prob. 150PCh. 3 - What is a conduction shape factor? How is it...Ch. 3 - What is the value of conduction shape factors in...Ch. 3 - Prob. 153PCh. 3 - A thin-walled cylindrical container is placed...Ch. 3 - Prob. 155PCh. 3 - Prob. 156PCh. 3 - Prob. 157PCh. 3 - Prob. 158EPCh. 3 - Prob. 159PCh. 3 - Prob. 160PCh. 3 - Prob. 161PCh. 3 - Prob. 162PCh. 3 - Prob. 163PCh. 3 - Prob. 164PCh. 3 - Consider a house with a flat roof whose outer...Ch. 3 - Prob. 166PCh. 3 - Radioactive material, stored in a spherical vessel...Ch. 3 - What is the R-value of a wall? How does it differ...Ch. 3 - What is effective emissivity for a plane-parallel...Ch. 3 - Prob. 170CPCh. 3 - What is a radiant barrier? What kinds of materials...Ch. 3 - Consider a house whose attic space is ventilated...Ch. 3 - Prob. 173PCh. 3 - Prob. 174PCh. 3 - Prob. 175PCh. 3 - Prob. 176PCh. 3 - Prob. 177PCh. 3 - Prob. 178PCh. 3 - Determine the winter R-value and the U-factor of a...Ch. 3 - The overall heat transfer coefficient (the...Ch. 3 - Prob. 181EPCh. 3 - Determine the summer and winter R-values. in m2 ....Ch. 3 - The overall heat transfer coefficient of a wall is...Ch. 3 - Two homes are identical, except that the walls of...Ch. 3 - Prob. 185PCh. 3 - Consider two identical people each generating 60 V...Ch. 3 - Cold conditioned air at 12C is flowing inside a...Ch. 3 - Hot water is flowing at an average velocity of 1.5...Ch. 3 - Prob. 189PCh. 3 - Prob. 190PCh. 3 - Prob. 191PCh. 3 - Prob. 192PCh. 3 - Prob. 193PCh. 3 - Prob. 194PCh. 3 - Prob. 195PCh. 3 - Prob. 196PCh. 3 - Prob. 197PCh. 3 - A total of 10 rectangular aluminum fins...Ch. 3 - Prob. 199PCh. 3 - A plane wall surface at 200C is to be cooled with...Ch. 3 - Prob. 201PCh. 3 - Prob. 202PCh. 3 - Prob. 203PCh. 3 - Prob. 204PCh. 3 - A 0.6-rn-diameter, 1.9-rn-long cylindrical tank...Ch. 3 - Prob. 206PCh. 3 - Prob. 207PCh. 3 - A thin-walled spherical tank is buried in the...Ch. 3 - Heat is lost at a rate of 275 W per m2 area of a 1...Ch. 3 - Prob. 210PCh. 3 - Heat is generated steadily in a 3-cm-diameter...Ch. 3 - Prob. 212PCh. 3 - Prob. 213PCh. 3 - Prob. 214PCh. 3 - Prob. 215PCh. 3 - Prob. 216PCh. 3 - Consider two walls. A and B, with the same surface...Ch. 3 - Prob. 218PCh. 3 - A room at 20C air temperature is losing heat to...Ch. 3 - Prob. 220PCh. 3 - A 1-cm-diameter, 30cm-long fin made of aluminum...Ch. 3 - A hot surface at 80C in air at 20C is to be cooled...Ch. 3 - A cylindrical pin fin of diameter 0.6 cm and...Ch. 3 - A 3-cm-long. 2-nuti x 2-mm rectangular...Ch. 3 - Two finned surfaces with long fins are identical,...Ch. 3 - A 20-cm-diameter hot sphere at 120C is buried in...Ch. 3 - A 25-cm-diameter, 2.4-rn-long vertical cylinder...Ch. 3 - Prob. 228PCh. 3 - The walls of a food storage facility are made of a...Ch. 3 - The equivalent thermal resistance for the thermal...Ch. 3 - Prob. 231PCh. 3 - Prob. 232PCh. 3 - Prob. 233PCh. 3 - The fin efficiency is defined as the ratio of the...Ch. 3 - Prob. 235PCh. 3 - In the United States, building insulation is...Ch. 3 - Prob. 237PCh. 3 - A plane brick wall (k=0.7W/m.K) and is 10 cm...Ch. 3 - The temperature in deep space is close to absolute...Ch. 3 - In the design of electronic components, it is...Ch. 3 - Using cylindrical samples of the same material,...Ch. 3 - Find out about the wall construction of the cabins...Ch. 3 - Prob. 243PCh. 3 - A house with 200-m2 floor space is to be heated...
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
- Using a AutoCAD drawing the section view for the following multiview drawingarrow_forwardCan you help me by providing the MATLAB code?arrow_forwardThe figure illustrates the nonpermanent connection of a steel cylinder head to a grade 30 cast-iron pressure vessel using 73 bolts. A confined gasket seal has an effective sealing diameter D of 0.9 m. The cylinder pressure is cycled between a minimum pressure of zero and a maximum pressure p, of 535 kPa. For the specifications given in the table for the specific problem assigned, select a suitable bolt length from the preferred sizes. Use Table A-17 for calculation purposes. Parameter Head thickness, A Cylinder thickness, B Value 16 mm 25 mm Internal diameter of the cylinder, C 0.8 m Gasket sealing diameter, D Bolt circle diameter, E Outer diameter of the cylinder head, F 0.9 m 1.0 m 1.1 m Bolt grade ISO 10.9 Bolt diameter, d 10 mm F E D 111 Find a suitable bolt length. Then, determine the bolt stiffness, material stiffness and stiffness constant of the joint. The bolt length is The bolt stiffness is mm. MN/m. The material stiffness is | The stiffness constant is MN/m.arrow_forward
- Problem 3 A rotating shaft of 20 mm diameter is simply supported. The shaft is loaded with a transverse load of 10 kN as shown in the figure. The shaft is made from AISI 1095 hot-rolled steel. The surface has been machined. The shaft operate at temperature T = 450 °C. Consider a reliability factor of 95%. Determine (a) Calculate the reaction forces R₁ and R2* (b) Draw the shear force and bending moment diagrams and determine the maximum bending moment and shear force. 200 mm 20 mm 10,000 N -50 mm- C A B R₁ Not to scale. (c) Determine the critical location of the shaft and the maximum effective stresses, (d) Calculate the static safety factor against yielding. (e) Determined the endurance limit, adjusted as necessary with Marin factors. (f) Calculate the fatigue factor of safety based on achieving infinite life (g) If the fatigue factor of safety is less than 1, then estimate the life of the part in number of rotations, based on the ultimate strength of the material at T = 450 °C.arrow_forwardAn air duct heater consists of an aligned array of electrical heating elements in which the longitudinal and transverse pitches are SL = ST = 24 mm. There are 3 rows of elements in the flow direction (NL = 3) and 4 elements per row (NT = 4). Atmospheric air with an upstream velocity of 12 m/s and a temperature of 25°C moves in cross flow over the elements, which have a diameter of 12 mm, a length of 250 mm, and are maintained at a surface temperature of 350°C. (a) Determine the total rate of heat transfer to the air and the temperature of the air leaving the duct heater. (b) Determine the pressure drop across the element bank and the fan power requirement. (c) Compare the average convection coefficient obtained in your analysis with the value for an isolated (single) element. Explain the difference between the results. (d) What effect would increasing the longitudinal and transverse pitches to 30 mm have on the exit temperature of the air, the total heat rate, and the…arrow_forwardWhat is the elongation of the rod in inches? And what is the change in diameter? I dont want either answer rounded please! Thank you.arrow_forward
- Draw the shear and bending-moment diagrams for the beam and loading shown, and determine the maximum absolute value of (a) the shear, (b) the bending moment. 300 lb 240 lb 360 lb C D E A 4 in. 3 in. 4 in. 5 in. Fig. P12.5arrow_forwardA commercial office building is located in the city of Lansing, Michigan, and is heatedusing a gaseous fuel with a heating value of 725 Btu/std ft3. The indoor designtemperature is 71ºF. The heat load for the building is known to be 250,000 Btu/hr. Thisheat load accounts for the fact that there are internal heat gains in the building, due tothe presence of people and electronic equipment (e.g., lights and radios). People in thebuilding are usually seated and involved in light activity.a) The furnace had an initial efficiency factor of 73% when installed, but since thenefficiency-improvement retrofits were implemented that raised the efficiency factorto its present value of 82%. The building was designed using the 99% designheating temperature value for the city to determine the outdoor design temperature.Evaluate the annual fuel quantity (in std ft3) required to heat the building, using thedegree-day or bin method.b) Seventy people use the building, but the occupancy pattern for the…arrow_forwardThe volumetric flow rate of air through a duct transition of the type shown in Table 12-9b (rectangular with two parallel sides) is 2 m3/s. The duct before the transition issquare, with a height of 50 cm. The expansion ratio across the transition is 4 (i.e., theduct area after the transition is 4 times greater than the duct area before the transition).a) Determine the pressure loss (in Pa) across the transition if the exit from the duct isabrupt (i.e., the diverging angle of the transition is 180º).b) Determine the percentage reduction in pressure loss for a transition diverging angleof 20º compared to the one in part (a).c) The head HVAC engineer requires the pressure loss across the transition to bereduced to less than 50% of the pressure loss for an abrupt exit (i.e., the case in part(a)), and suggests a transition diverging angle of 45º. Will this new diverging angleachieve the required reduction in pressure loss? Justify your answer.d) For a transition diverging angle of 90º, the…arrow_forward
- The volumetric flow rate of air through a duct transition of the type shown in Table 12-9b (rectangular with two parallel sides) is 2 m3/s. The duct before the transition issquare, with a height of 50 cm. The expansion ratio across the transition is 4 (i.e., theduct area after the transition is 4 times greater than the duct area before the transition).a) Determine the pressure loss (in Pa) across the transition if the exit from the duct isabrupt (i.e., the diverging angle of the transition is 180º).b) Determine the percentage reduction in pressure loss for a transition diverging angleof 20º compared to the one in part (a).c) The head HVAC engineer requires the pressure loss across the transition to bereduced to less than 50% of the pressure loss for an abrupt exit (i.e., the case in part(a)), and suggests a transition diverging angle of 45º. Will this new diverging angleachieve the required reduction in pressure loss? Justify your answer.d) For a transition diverging angle of 90º, the…arrow_forwardAuto Controls The figure is a schematic diagram of an aircraft elevator control system. The input to the systemin the deflection angle of the control lever , and the output is the elevator angle phi.show that for each angle theta of the control lever ,there is a corresponding elevator angle phi. Then find Y(s)/theta(s) and simplify the resulting transfer function . Also note from the diagram that y and phi is related Show full solution, no copied solutionsarrow_forwardhand-written solutions only. correct answers upvotedarrow_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
Understanding Conduction and the Heat Equation; Author: The Efficient Engineer;https://www.youtube.com/watch?v=6jQsLAqrZGQ;License: Standard youtube license