INTRO.TO HEAT TRANSFER-W/ETEXT
6th Edition
ISBN: 9781118738764
Author: Bergman
Publisher: WILEY
expand_more
expand_more
format_list_bulleted
Question
Chapter 1, Problem 1.26P
To determine
The maximum allowable chip power with air and with dielectric liquid as coolant.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A 50-cm-diameter pipeline in the Arctic carries hot oil at 30◦C and is exposed to a surrounding temperature of −20◦C. A special powder insulation 5 cm thick surrounds the pipe and has a thermal conductivity of 7 mW/m · ◦C. The convection heat-transfer coefficient on the outside of the pipe is 9 W/m2 · ◦C. Estimate the energy loss from the pipe per meter of length.
(Please give step-by-step solution)
The inner diameter of a pipe made of %1 C steel used in the drying machine of a textile factory is D1 = 160 mm and the thread diameter is D₂= 170 mm. The pipe is insulated with 25 mm thick glass wool. The heat transfer coefficient between the air and the pipe surface at 90 °C temperature inside the pipe is 80 W/m²K. The temperature of the ambient air outside the insulation is 20 °C and the air comes perpendicular to the cat wool surface at a speed of 10 m/s. Find the total heat transfer coefficient according to the inside diameter of the pipe. Calculate the heat transfer per unit length of pipe per unit time ?
A thick-walled cylindrical tubing of hard rubber (k=0.151 W/m*K) having an inside radius of 5 mm and an outside radius of 20 mm is being used as a temporary cooling coil in a bath. Ice water is flowing rapidly inside, and the inside wall temperature is 275 K. The outside surface temperature is 300 K. A total of 20 W must be removed from the bath by the cooling coil. How many meter of tubing are needed?
Chapter 1 Solutions
INTRO.TO HEAT TRANSFER-W/ETEXT
Ch. 1 - The thermal conductivity of a sheet of rigid,...Ch. 1 - The heat flux that is applied to the left face of...Ch. 1 - A concrete wall, which has a surface area of 20m2...Ch. 1 - The concrete slab of a basement is 11 m long, 8 m...Ch. 1 - Consider Figure 1.3. The heat flux in the...Ch. 1 - Prob. 1.6PCh. 1 - The inner and outer surface temperatures of a...Ch. 1 - A thermodynamic analysis of a proposed Brayton...Ch. 1 - A glass window of width W=1m and height H=2m is 5...Ch. 1 - Prob. 1.10P
Ch. 1 - The heat flux that is applied to one face of a...Ch. 1 - Prob. 1.12PCh. 1 - Prob. 1.13PCh. 1 - Prob. 1.14PCh. 1 - The 5-mm-thick bottom of a 200-mm-diameter pan may...Ch. 1 - Prob. 1.16PCh. 1 - For a boiling process such as shown in Figure...Ch. 1 - You've experienced convection cooling if you've...Ch. 1 - Prob. 1.19PCh. 1 - A wall has inner and outer surface temperatures of...Ch. 1 - An electric resistance heater is embedded in a...Ch. 1 - Prob. 1.22PCh. 1 - A transmission case measures W=0.30m on a side and...Ch. 1 - Prob. 1.24PCh. 1 - A common procedure for measuring the velocity of...Ch. 1 - Prob. 1.26PCh. 1 - Prob. 1.27PCh. 1 - Prob. 1.28PCh. 1 - Prob. 1.29PCh. 1 - Prob. 1.30PCh. 1 - Prob. 1.31PCh. 1 - Prob. 1.32PCh. 1 - Prob. 1.33PCh. 1 - Prob. 1.34PCh. 1 - An electrical resistor is connected to a battery,...Ch. 1 - Pressurized water pin=10bar,Tin=110C enters the...Ch. 1 - Consider the tube and inlet conditions of Problem...Ch. 1 - An internally reversible refrigerator has a...Ch. 1 - A household refrigerator operates with cold- and...Ch. 1 - Chips of width L=15mm on a side are mounted to a...Ch. 1 - Consider the transmission case of Problem 1.23,...Ch. 1 - One method for growing thin silicon sheets for...Ch. 1 - Heat is transferred by radiation and convection...Ch. 1 - Radioactive wastes are packed in a long,...Ch. 1 - An aluminum plate 4 mm thick is mounted in a...Ch. 1 - A blood warmer is to be used during the...Ch. 1 - Consider a carton of milk that is refrigerated at...Ch. 1 - The energy consumption associated with a home...Ch. 1 - Liquid oxygen, which hems a boiling point of 90 K...Ch. 1 - The emissivity of galvanized steel sheet, a common...Ch. 1 - Three electric resistance heaters of length...Ch. 1 - A hair dryer may be idealized as a circular duct...Ch. 1 - In one stage of an annealing process, 304...Ch. 1 - Convection ovens operate on the principle of...Ch. 1 - Annealing, an important step in semiconductor...Ch. 1 - In the thermal processing of semiconductor...Ch. 1 - A furnace for processing semiconductor materials...Ch. 1 - Single fuel cells such as the one of Example 1.5...Ch. 1 - Prob. 1.59PCh. 1 - Prob. 1.60PCh. 1 - Prob. 1.61PCh. 1 - A small sphere of reference-grade iron with a...Ch. 1 - A 50mm45mm20mm cell phone charger has a surface...Ch. 1 - A spherical, stainless steel (AISI 302) canister...Ch. 1 - Prob. 1.65PCh. 1 - Prob. 1.66PCh. 1 - A photovoltaic panel of dimension 2m4m is...Ch. 1 - Following the hot vacuum forming of a paper-pulp...Ch. 1 - Prob. 1.69PCh. 1 - Prob. 1.70PCh. 1 - Prob. 1.71PCh. 1 - The roof of a car in a parking lot absorbs a solar...Ch. 1 - Prob. 1.73PCh. 1 - Prob. 1.74PCh. 1 - Consider Problem 1.1. If the exposed cold surface...Ch. 1 - Prob. 1.76PCh. 1 - Prob. 1.77PCh. 1 - A thin electrical heating element provides a...Ch. 1 - Prob. 1.79PCh. 1 - Prob. 1.80PCh. 1 - Prob. 1.81PCh. 1 - The curing process of Example 1.9 involves...Ch. 1 - The diameter and surface emissivity of an...Ch. 1 - Bus bars proposed for use in a power transmission...Ch. 1 - A solar flux of 700W/m2 is incident on a...Ch. 1 - In considering the following problems involving...
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
- An electrical transmission line of 1.2-cm diameter carries a current of 200 amps and has a resistance of 310-4 ohm per meter of length. If the air around this line is at v, determine the surface temperature on a windy day, assuming a wind blows across the line at 33 km/h.arrow_forwardCalculate the heat losses per unit length in a horizontal tube with an outside diameter of 15 cm, if its surface is kept at 400 K AND the surrounding air has a temperature of 300 K and a pressure of 1 bar.The properties of air at a pressure of 1 bar and a film temperature of 350 K are: In this case, v = 20.76 x 10-6 m2/s , α = 0.2983 x 10-4 m2/s, k = 0.03003 W/mK, Pr = 0.697, β = 2.86 x 10-3 K-1arrow_forwardEstimate the natural convection heat transfer coefficient of the horizontal pipe. The outer surface temperature of the pipe is 100 ° C. The ambient air temperature is 35 ° C. The outer diameter of the pipe is 15 cm. Convection coefficient = W / m² ° C.arrow_forward
- Find the minimum amount of diameter for the insulation of a spherical water tank? Radius of the tank is 10 m, thermal conductivity is 25 W/(m^2*K) and convective coefficient is 5 W/(m*K) 8 m not sufficient information 10 m 20 m 15 marrow_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_forwardA 5.0-cm-diameter cylinder is heated to a temperature of 200°C, and air at 30 °C forced across it at a velocity of 50 m/s (h = 180 W/m2 K). If the surface emissivity is 0.7, calculate the total heat loss per unit length if the walls of the enclosing room are at 10 °C. Comment on your calculation.arrow_forward
- Engine Oil at 58.95 degrees celsius Flows over a 5m long flat plate whose temperature is 20.11 degrees celsius with a velocity of 2.2m/s. Determine the rate of heat transfer (W), considering forced convection, per unit width of the entire plate. Density = 876kg/m^3 Thermal conductivity = 0.144W/m-K Pr = 2870 dynamic viscosity = 0.21kg/m-s Q = ?arrow_forwardA long 8-cm diameter vertical steam pipe whose external surface temperature is 90 degrees C passes through some open area that is not protected against the wind blows. Determine the rate of heat loss from the pipe per unit length when the air is at 1 atm, 7 degrees Celsius and the wind is blowing across the pipe at a velocity of 50 km/h. From Table A-1:Thermal conductivity, k = 0.0275 W/m degrees Celsius ,viscosity, v = 1.77 x 10^-5 m^2/sPrandtl no. Pr = 0.71arrow_forwardHot water, k=48 W/m. It flows at a speed of 1.4 m/s along the cast iron pipe at oC. The inner and outer diameters of the pipe are 3.0 and 3.5 cm, respectively. The pipe is located within 15 m of a basement with a temperature of 15 °C. If the temperature of the water drops from 70 oC to 67 oC while passing through the basement and the film heat transfer coefficient on the inner surface of the pipe is 400 W/m2. Calculate the convective heat transfer coefficient on the outer surface of the pipe and the heat to be transferred.arrow_forward
- In an oil cooler, 216 kg/h of hot oil enters a thin metal pipe of diameter 25 mm. An equal mass of cooling water flows through the annular space between the pipe and a larger concentric pipe; the oil and water moving in opposite directions. The oil enters at 420 K and is to be cooled to 320 K. If the water enters at 290 K, what length of pipe will be required? Take coefficients of 1.6 kW/m2 K on the oil side and 3.6 kW/m2 K on the water side and 2.0 kJ/kg K for the specific heat of the oil.arrow_forwardcylindrical fuel element for a gas-cooled nuclear reactor, the heat generation rate within the fuel element due to fission can be approximated by the relation: q(r) = q_0 [1 - (r/a)^2] W/m^3 where a is the radius of the fuel element and q_0 is constant. The boundary surface at r = a is maintained at a uniform temperature T_0. Assuming one-dimensional, steady-state heat flow, develop a relation for the temperature drop from the centerline to the surface of the fuel element. For radius a= 30mm, the thermal conductivity k = 10 W/m middot K and q_0 = 2 times 10^7 W/m^3, calculate the temperature drop from the centerline to the surface.arrow_forwardFind the minimum amount of diameter for the insulation of a spherical water tank? Radius of the tank is 10 m, thermal conductivity is 25 W/(m^2*K) and convective coefficient is 5 W/(m*K)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
Heat Transfer – Conduction, Convection and Radiation; Author: NG Science;https://www.youtube.com/watch?v=Me60Ti0E_rY;License: Standard youtube license