Evaluate the dimensionless groups hcD/k, U? Dp/?, cp ?/k for water, n-Butyl alcohol, mercury, hydrogen, air, and saturated steam at a temperature of 100°C. Let D = 1 m, U? = 1 m/sec, and hc = 1 W/(m2 K).
GIVEN
D = 1 m
U? = 1 m/s
hc = 1 W/(m2 K)
FIND
The dimensionless groups
? hc D/k (Nusselt number)
? U? D p/? (Reynolds number)
? cp ?/k (Prandtl number)
PROPERTIES AND CONSTANTS
From Appendix 2, at 100°C
For water at 100°C
The dimensionless groups for the other substances can be calculated in a similar manner
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