Answer:
98,614.82 W/m²
Explanation:
Where;
Q = the amount of heat loss from the pipe
h = the heat transfer coefficient of the pipe = 50 W/m².K
T₁ = the ambient temperature of the pipe = 30⁰C
T₂ = the outside temperature of the pipe = 100⁰C
L= the length of pipe
r₁ = inner radius of the pipe = 20mm
r₂ = outer radius of the pipe = 25mm
To determine the amount of heat loss from the pipe per unit length
From the equation above
= 98,614.82 W/m²
Answer:
Given Data:
concentration of sewer Csewer = 1.2 g/L
converting into mg/L = Csewer = 1.2 g/L x 1000 mg/g = 1200 mg/L
flow rate of sewer Qsewer = 2000 L/min
concentration of sewer Cstream = 20 mg/L
flow rate of sewer Qstream = 2m3/s
converting Q into L/min = 2m3/s x 1000 x 60 = 120000 L/min
mass diagram is
Answer:
The inside temperature, is approximately 248 °C.
Explanation:
The parameters given are;
Temperature of the air = 20°C
Carbon steel surface temperature 250°C
Area of surface = 50 cm × 75 cm = 0.5 × 0.75 = 0.375 m²
Convection heat transfer coefficient = 25 W/(m²·K)
Heat lost by radiation = 300 W
Assumption,
Air temperature = 20 °C
Hot plate temperature = 250 °C
Thermal conductivity K = 65.2 W/(m·K)
Steady state heat transfer process
One dimensional heat conduction
We have;
Newton's law of cooling;
q = h×A×( -
) + Heat loss by radiation
= 25×0.325×(250 - 20) + 300
= 2456.25 W
The rate of energy transfer per second is given by the following relation;
Thermal conductivity K = 65.2 W/(m·K)
Therefore;
The inside temperature, = 247.99 °C ≈ 248 °C.