Pressurized Steam Flow: Calculating Heat Loss Per Unit Length of Pipe

Calculation of Heat Loss Per Unit Length of Pipe

Heat loss per unit length of pipe : q' = 1363.47 W/m

Explanation

The heat loss per unit length of the pipe is calculated based on the provided data and assumptions. The calculation involves determining the heat rate expression and utilizing the shape factor for a circular cylinder centered in a square solid of equal length.

Assumptions

• Steady-state conditions
• Negligible steam side convection resistance, pipe wall resistance, and contact resistance (T₁ = 450 K)
• Constant properties

Calculation Steps

1. Find the thermal conductivity for concrete (1.7 W/mK for stone concrete).
2. Determine the shape factor for a circular cylinder in a square solid of equal length (S = 2πL ÷ [ln(1.08w/D)]).
3. Calculate the heat loss per unit length using the formula q' = 2πk(T₁ - T₂) ÷ [ln(1.08w/D)].
4. Substitute the known values (k = 1.7 W/mK, T₁ = 450 K, T₂ = 300 K, w = 1.5 m, D = 0.5 m) to get the final result.
5. The heat loss per unit length of the pipe is found to be 1363.47 W/m.