PROBLEM 1.1
KNOWN: Heat rate, q, through one-dimensional wall of area A, thickness L, thermal
conductivity k and inner temperature, T1.
FIND: The outer temperature of the wall, T2.
SCHEMATIC:
ASSUMPTIONS: (1) One-dimensional conduction in the x-direction,
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conductivity k and inner temperature, T1. FIND: The outer temperature of the wall, T2. SCHEMATIC:
ASSUMPTIONS: (1) One-dimensional conduction in the x-direction,
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PROBLEM 13.1
KNOWN: Various geometric shapes involving two areas A1 and A2. FIND: Shape factors, F12 and F21, for each configuration. ASSUMPTIONS: Surfaces are diffuse. ANALYSIS: The analysis is not to make use of tables or charts. The approach involves u
PROBLEM 12.1
KNOWN: Rate at which radiation is intercepted by each of three surfaces (see (Example 12.1). FIND: Irradiation, G[W/m ], at each of the three surfaces. SCHEMATIC:
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ANALYSIS: The irradiation at a surface is the rate at which radiation is inci
PROBLEM 11.1
KNOWN: Initial overall heat transfer coefficient of a fire-tube boiler. Fouling factors following one year's application. FIND: Whether cleaning should be scheduled. SCHEMATIC:
ASSUMPTIONS: (1) Negligible tube wall conduction resistance, (2)
PROBLEM 6.1 KNOWN: Variation of hx with x for laminar flow over a flat plate. FIND: Ratio of average coefficient, h x , to local coefficient, hx, at x. SCHEMATIC:
ANALYSIS: The average value of hx between 0 and x is hx = hx hx Hence, 1 x C x h x dx = x -1
PROBLEM 5.1 KNOWN: Electrical heater attached to backside of plate while front surface is exposed to convection process (T,h); initially plate is at a uniform temperature of the ambient air and suddenly heater power is switched on providing a constant q .
PROBLEM 3.1 KNOWN: One-dimensional, plane wall separating hot and cold fluids at T,1 and T ,2 , respectively. FIND: Temperature distribution, T(x), and heat flux, q , in terms of T,1 , T,2 , h1 , h 2 , k x and L. SCHEMATIC:
ASSUMPTIONS: (1) One-dimensiona
PROBLEM 2.1
KNOWN: Steady-state, one-dimensional heat conduction through an axisymmetric shape. FIND: Sketch temperature distribution and explain shape of curve. SCHEMATIC:
ASSUMPTIONS: (1) Steady-state, one-dimensional conduction, (2) Constant properties