The free convection heat transfer coefficient on a thin hot vertical plate suspended in still air can be determined from observations of the change in plate temperature with time as it cools. Assuming the plate is isothermal and radiation exchange with its surroundings is negligible, evaluate the convection coefficient at the instant of time when…
An electric resistance heater is embedded in a long cylinder of diameter 30mm. When water with a temperature of 25degree C and velocity of 1 m/s flows crosswise over the cylinder, the power per unit length required to maintain the surface at a uniform temperature of 90degreeC is 28kW/m. When air is also at 25…
The heat flux through a wood slab 50 mm thick, whose inner and outer surface temperatures are 40 and 20 degree C. respectively, has been determined to be 40 W/m2. What is the thermal conductivity of the wood? All sample problems and notes are based on the following textbook: Fundamentals of Heat and Mass Transfer…
What is the thickness required of a masonry wall having thermal conductivity 0.75 W/m K if the heat rate is to be 80% of the heat rate through a composite structural wall having a thermal conductivity of 0.25 W/m K and a thickness of 100 mm? Both walls are subjected to the same surface temperature…
All sample problems and notes are based on the following textbook: Fundamentals of Heat and Mass Transfer Seventh Edition ISBN-13: 9780470501979 ISBN-10: 0470501979 Edition: 7 Author: Theodore L. Bergman, Adrienne S. Lavine, Frank P. Incropera, David P. DeWitt Publication date: 2011 Publisher: Wiley Format: Hardcover 1072 pages