System Dynamics
3rd Edition
ISBN: 9780073398068
Author: III William J. Palm
Publisher: MCG
expand_more
expand_more
format_list_bulleted
Textbook Question
Chapter 7, Problem 7.47P
A certain radiator wall is made of copper with a conductivity k — 47 lb/sec-°F at 212°F. The wall is 3/16 in. thick and has circulating water on one side with a convection coefficient /i j =85 lb/sec-ft-°F. A fan blows air over the other side, which has a convection coefficient /h = 15 lb/sec-ft-°F. Find the thermal resistance of the radiator on a square foot basis.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
One wall of a room measures 14 feet long and 8 feet high.
It's contains a window 5 feet wide and 3.5 feet high. The wall has an R-Value of 15.5. the unit R-value of the window is 3.5. Find the rate of heat flow through the wall when the inside air temperature is 68 degrees Fahrenheit and the outside temperature is 5 degrees Fahrenheit.
(Picture of problem attached)
A wood wall 2.5 m (» 8 ft) ´ 7 m (» 23 ft) ´ 2.5 cm (» 1 in) thick has thermal conductivity k = 0.1 W/Km.
A. Find the R-value of the wall (in SI units, of course).
B. If the inside and outside temperatures are 20°C and 5°C respectively, find the heat flow in watts passing through the wall.
C. Now include the R-values of the air layers inside (Rin = 0.12 m^2 K/W) and outside (Rout = 0.06 m^2 K/W) the wall. Find the new heat flow. (Note: Just add all the R’s.)
D. Add 10 cm of fiberglass (kf = 0.05 W/Km) to the wall. Find the R-value of the fiberglass layer.
E. Find the heat flow through the wall in Watts, including air, wood, and fiberglass.
HEAT TRANSFER:
A thick-walled nuclear coolant pipe (k = 12.5 Btu/hr-ft-°F) with 10 in. inside diameter and 12 in. outside diameter is covered with a 3 in. layer of asbestos insulation (k 0.14 = Btu/hr-ft-°F). If the inside wall temperature of the pipe is maintained at 550°F, (a) calculate the heat loss per foot of length. The outside temperature is 100°F. (b) Find the interface temperature between the pipe and the insulation.
Chapter 7 Solutions
System Dynamics
Ch. 7 - Prob. 7.1PCh. 7 - Refer to the water storage and supply system shown...Ch. 7 - Prob. 7.3PCh. 7 - In Figure P7.4 the piston of area A is connected...Ch. 7 - Refer to Figure 7.1.4a. and suppose that p\ — p2=...Ch. 7 - Pure water flows into a mixing tank of volume V =...Ch. 7 - Consider the mixing tank treated in Problem 7.6....Ch. 7 - Derive the expression for the fluid capacitance of...Ch. 7 - Prob. 7.9PCh. 7 - Prob. 7.10P
Ch. 7 - 7.11 Derive the expression for the capacitance of...Ch. 7 - Air flows in a certain cylindrical pipe 1 m long...Ch. 7 - Derive the expression for the linearized...Ch. 7 - Consider the cylindrical container treated in...Ch. 7 - A certain tank has a bottom area A = 20 m2. The...Ch. 7 - A certain tank has a circular bottom area A = 20...Ch. 7 - The water inflow rate to a certain tank was kept...Ch. 7 - Prob. 7.18PCh. 7 - Prob. 7.19PCh. 7 - In the liquid level system shown in Figure P7.20,...Ch. 7 - The water height in a certain tank was measured at...Ch. 7 - Derive the model for the system shown in Figure...Ch. 7 - (a) Develop a model of the two liquid heights in...Ch. 7 - Prob. 7.24PCh. 7 - Design a piston-type damper using an oil with a...Ch. 7 - Prob. 7.26PCh. 7 - 7.27 An electric motor is sometimes used to move...Ch. 7 - Prob. 7.28PCh. 7 - Prob. 7.29PCh. 7 - Figure P7.3O shows an example of a hydraulic...Ch. 7 - Prob. 7.31PCh. 7 - Prob. 7.32PCh. 7 - Prob. 7.33PCh. 7 - Prob. 7.34PCh. 7 - Prob. 7.35PCh. 7 - Prob. 7.36PCh. 7 - Prob. 7.37PCh. 7 - (a) Determine the capacitance of a spherical tank...Ch. 7 - Obtain the dynamic model of the liquid height It...Ch. 7 - Prob. 7.40PCh. 7 - Prob. 7.41PCh. 7 - Prob. 7.42PCh. 7 - Prob. 7.43PCh. 7 - Prob. 7.44PCh. 7 - Prob. 7.45PCh. 7 - The copper shaft shown in Figure P7.46 consists of...Ch. 7 - A certain radiator wall is made of copper with a...Ch. 7 - A particular house wall consists of three layers...Ch. 7 - A certain wall section is composed of a 12 in. by...Ch. 7 - Prob. 7.50PCh. 7 - Prob. 7.51PCh. 7 - A steel tank filled with water has a volume of...Ch. 7 - Prob. 7.53PCh. 7 - Prob. 7.54PCh. 7 - Prob. 7.55P
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
- A room has a pine ceiling [ k = 0.12 W/(m•C°) ] that measures 3.0 m x 4.0 m x 2.0 cm. On a cold day, the temperature inside the room is 20°C, and the temperature in the attic above is 8°C. If 6.0 cm of glass wool insulation [ k = 0.042 W/(m•C°) ] were put in above the ceiling, how much energy would be saved in one hour? Please use gresa methodarrow_forwardA steel pipe (outside diameter 100 mm) is covered with two layers of insulation. The inside layer, 40 mm thick, has a thermal conductivity of 0.07 W/(m K). The outside layer, 20 mm thick, has a thermal conductivity of 0.15 W/(m K). The pipe is used to convey steam at a pressure of 600 kPa. The outside temperature of insulation is 24°C. If the pipe is 10 m long, determine the following, assuming the resistance to conductive heat transfer in steel pipe and convective resistance on the steam side are negligible: a. The heat loss per hour. b. The interface temperature of insulation.arrow_forward4. A spherical steel reaction vessel has an outer radius of 2.0 m and is covered in lagging 250mm thick. The thermal conductivity of the lagging is 0.4 W/m K. The temperature at the surface of the steel is 340⸰C and the surface temperature of the lagging is 45 ⸰ Calculate the heat loss.Thermal Conductivity;k=385 W/mKarrow_forward
- Two cylinders, 0.75 m in diameter (upper cylinder is 1.5 m long, k = 0.5 W/m-K; lower cylinder is 1.1 m long, k = 1.3 W/m-K) are inside a frustum of a square pyramid (k = 0.053 W/m-K) as shown in the diagram. The upper face is at 250 oC and the lower base is at 100 oC. Calculate the resistance in A (in K/W).arrow_forwardA gas vessel 1.5m x 1.5m x 2m containing Carbon Dioxide (CO2) with a temperature of -3°C. The right vessel wall is fixed to the wall, as shown in Figure Q1 (a). A minimum force of 10kN is required to split/open the gas vessel. Calculate: i. Vacuum pressure of CO2.ii. Mass of the CO2. Take molecular weight for Oxygen= 16, Carbon = 12, atmosphericpressure 100kPa, and universal gas constant = 8314 J⋅kmol−1⋅K−1arrow_forwardTwo cylinders, 0.75 m in diameter (upper cylinder is 1.5 m long, k = 0.5 W/m-K; lower cylinder is 1.1 m long, k = 1.3 W/m-K) are inside a frustum of a square pyramid (k = 0.053 W/m-K) as shown in the diagram. The upper face is at 250 oC and the lower base is at 100 oC. Calculate the resistance in C (in K/W).arrow_forward
- Two vessels of different shape and sizes are connected by means of a pipe with a valve. Vessel A has a diameter of 4 ft and the length is 1.8 m at the given pressure gauge of 1476.4 in Hg and temperature of 82°F. Another vessel spherical in shape contains the same gas at 15,000 torr gauge and 18°C. The valve is opened and when the properties have been determined, it is found out that the gauge pressure is 35.7 kgf/cm2 and the temperature is 21°C. If the barometric pressure is 755 mm Hg, find the following: Volume of Vessel A in in3 Pressure at Vessel A in psia Temperature at Vessel A in °R Pressure at Vessel B in psiaarrow_forwardTwo vessels of different shape and sizes are connected by means of a pipe with a valve. Vessel A has a diameter of 4 ft and the length is 1.8 m at the given pressure gauge of 1476.4 in Hg and temperature of 82°F. Another vessel spherical in shape contains the same gas at 15,000 torr gauge and 18°C. The valve is opened and when the properties have been determined, it is found out that the gauge pressure is 35.7 kgf/cm2 and the temperature is 21°C. If the barometric pressure is 755 mm Hg. Question: What is the diameter of the spherical tank in inches if the gas is carbon dioxide?arrow_forwardTwo vessels of different shape and sizes are connected by means of a pipe with a valve. Vessel A has a diameter of 4 ft and the length is 1.8 m at the given pressure gauge of 1476.4 in Hg and temperature of 82°F. Another vessel spherical in shape contains the same gas at 15,000 torr gauge and 18°C. The valve is opened and when the properties have been determined, it is found out that the gauge pressure is 35.7 kgf/cm2 and the temperature is 21°C. If the barometric pressure is 755 mm Hg, find the following: Volume of Vessel A in in3 Pressure at Vessel A in psia Temperature at Vessel A in °R Pressure at Vessel B in psia Temperature at Vessel B in °R Pressure of the gas when mixed in psia Temperature of the gas when mixed in °R Atmospheric pressure in psi Main Question: What is the diameter of the spherical tank in inches if the gas is carbon dioxide?arrow_forward
- A furnace wall is constructed of a firebrick that is 6 inches thick. The temperature of the inside of the wall is 1300°F, and the temperature of the outside of the wall is 175°F. If the mean thermal conductivity under these conditions is 0.17 BTU/hr-ft-°F. What is the rate of heat loss through 10 square feet of wall surface?arrow_forwardA vertical cylinder 6 ft tall and 1 ft in diameter might be used to approximate a man for heat-transfer purposes. Suppose the surface temperature of the cylinder is 78°F, h=2 Btu/h · ft2 . °F, the surface emissivity is 0.9, and the cylinder is placed in a large room where the air temperature is 68°F and the wall temperature is 45°F. Calculate the heat lost from the cylinder. Repeat for a wall temperature of 80°F. What do you conclude from these calculations? Known, Find, Schematic Diagram, Assumption, Properties, Analysis and Commentsarrow_forwardA vertical cylinder 6 ft tall and 1 ft in diameter might be used to approximate a man for heat-transfer purposes. Suppose the surface temperature of the cylinder is 78°F, h=2 Btu/h · ft2 . °F, the surface emissivity is 0.9, and the cylinder is placed in a large room where the air temperature is 68°F and the wall temperature is 45°F. Calculate the heat lost from the cylinder. Repeat for a wall temperature of 80°F. What do you conclude from these calculations?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Elements Of ElectromagneticsMechanical EngineeringISBN:9780190698614Author:Sadiku, Matthew N. O.Publisher:Oxford University PressMechanics of Materials (10th Edition)Mechanical EngineeringISBN:9780134319650Author:Russell C. HibbelerPublisher:PEARSONThermodynamics: An Engineering ApproachMechanical EngineeringISBN:9781259822674Author:Yunus A. Cengel Dr., Michael A. BolesPublisher:McGraw-Hill Education
- Control Systems EngineeringMechanical EngineeringISBN:9781118170519Author:Norman S. NisePublisher:WILEYMechanics of Materials (MindTap Course List)Mechanical EngineeringISBN:9781337093347Author:Barry J. Goodno, James M. GerePublisher:Cengage LearningEngineering Mechanics: StaticsMechanical EngineeringISBN:9781118807330Author:James L. Meriam, L. G. Kraige, J. N. BoltonPublisher:WILEY
Elements Of Electromagnetics
Mechanical Engineering
ISBN:9780190698614
Author:Sadiku, Matthew N. O.
Publisher:Oxford University Press
Mechanics of Materials (10th Edition)
Mechanical Engineering
ISBN:9780134319650
Author:Russell C. Hibbeler
Publisher:PEARSON
Thermodynamics: An Engineering Approach
Mechanical Engineering
ISBN:9781259822674
Author:Yunus A. Cengel Dr., Michael A. Boles
Publisher:McGraw-Hill Education
Control Systems Engineering
Mechanical Engineering
ISBN:9781118170519
Author:Norman S. Nise
Publisher:WILEY
Mechanics of Materials (MindTap Course List)
Mechanical Engineering
ISBN:9781337093347
Author:Barry J. Goodno, James M. Gere
Publisher:Cengage Learning
Engineering Mechanics: Statics
Mechanical Engineering
ISBN:9781118807330
Author:James L. Meriam, L. G. Kraige, J. N. Bolton
Publisher:WILEY
Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license