Experimental results for heat transfer over a flat plate with an extremely rough surface were found to be correlated by an expression of the form Nux=0.04 Rex0.9 Pr1/3 where Nux is the local value of the Nusselt number at a position x measured from the leading edge of the plate. Obtain an expression for the ratio of the average heat transfer coefficient hˉx to the local coefficient hx

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…

A spherical interplanetary probe of 0.5-m diameter contains electronics that dissipate 150 W. If the probe surface has an emissivity of 0.8 and it does not receive radiation from other surfaces, such as the sun, what is the surface temperature of the probe? How useful was this post? Click on a star to rate it!…

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…

What are Low-E Windows? Low-E windows as defined by http://www.royalprime.com are windows that have two glass panes or more that selectively rejects certain energy which as a result, greatly decreases the amount of heat that transfer through the glass (window glossary, 2012). In this research paper I compare a standard egress double pane  double hung…

Radioactive wastes are packed in a long, thin-walled cylindrical container. The wastes generate thermal energy nonuniformly according to the relation q = qo [1 – (r/ro)2], where q is the local rate of energy generation per unit volume, qo is a constant, and ro is the radius of the container. Steady-state conditions are maintained by…

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…