Convection of Air in a Hot Oven
A vertical wall of an oven is 60 cm long and is covered with a metal sheet maintained at 170°C. Air temperature inside the oven is 90°C and the pressure is atmospheric. Calculate the local heat transfer coefficient at the end of the wall.
http://cse.gre.ac.uk/coursinf/cfd_exp.html
Since the specified pressure is atmospheric, air can be considered a low density fluid and the MATLAB programs grcalc and prcalc can be used.
Converting to SI units:
90°C = 363.15 K
170°C = 443.15 K
60 cm = 0.6 m
>> start301 (specify new session, E&M balances, ceng301 database, K as temperature, 1 compound: air)
>> Gr=grcalc(0.6,363.15,443.15)
ans =
6.0864e+08
The flow is laminar, and this value is in agreement with the book answer of 6.055e08 and can be used in combination with prcalc to determine the Nusselt number and the heat transfer coefficient.
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