Water at a temperature of T∞ = 25°C flows over one of the surfaces of a steel wall (AISI 1010) whose temperature is Ts,1 = 40°C and thermal conductivity of steel is 671 w/m.k. The wall is 0.35 m thick, and its other surface temperature is Ts,2 = 100°C. For steady state conditions what is the convection coefficient associated with the water flow

KNOWN: Expression for face-averaged Nusselt numbers on a cylinder of rectangular cross section. Dimensions of the cylinder. FIND: Average heat transfer coefficient over the entire cylinder. Plausible explanation for variations in the face-averaged heat transfer coefficients. SCHEMATIC: Air V = 10 m/s T = 300 K c = 40 mm ASSUMPTIONS: (1) Steady-state conditions, (2) Constant properties. d = 30 mm

An engineer seeks to study the effect of temperature on the curing of concrete by controlling the curing temperature in the following way. A sample slab of thickness L is subjected to a heat flux, qw, on one side, and it is cooled to temperature T1 on the other. Derive a dimensionless expression for the steady temperature in the slab. Plot the expression and offer a criterion for neglecting the internal heat generation in the slab.