🏗️ Double-Pipe Exchanger Sizing
Size a concentric double-pipe heat exchanger. Input convection coefficients, pipe diameters, and fouling factors to calculate required clean and fouled lengths, areas, and overall coefficients.
📝 Sizing Inputs
Thermal Sizing Equations:
Q = U_fouled × A_fouled × LMTD
L = A_fouled / (π × D_tube,out)
Overall Resistance:
1/U_fouled = 1/h_o + R_fo + ln(D_out/D_in)·D_out/(2·k_w) + R_fi·(D_out/D_in) + 1/h_i·(D_out/D_in)
Overdesign Percentage:
% Overdesign = (A_fouled - A_clean) / A_clean × 100
Q = U_fouled × A_fouled × LMTD
L = A_fouled / (π × D_tube,out)
Overall Resistance:
1/U_fouled = 1/h_o + R_fo + ln(D_out/D_in)·D_out/(2·k_w) + R_fi·(D_out/D_in) + 1/h_i·(D_out/D_in)
Overdesign Percentage:
% Overdesign = (A_fouled - A_clean) / A_clean × 100
📊 Results & Sizing Details
Configure the inputs and click "Size Double-Pipe Exchanger" to see calculation results.
ℹ️ About Double-Pipe Heat Exchangers
A double-pipe heat exchanger consists of one pipe concentrically placed inside another pipe of larger diameter. One fluid flows through the inner pipe, while the other flows through the annular space between them.
Key Sizing Principles:
• **Clean vs Fouled Condition**: Over time, scale and deposit layers build up on pipe surfaces. This fouling resistance decreases heat transfer rate. Designing with fouling factors ($R_f$) ensures the exchanger performs adequately over its operating life.
• **Convection Coefficients ($h_i, h_o$)**: The convective resistance depends heavily on flow velocities, fluid viscosities, and turbulence. Higher coefficients reduce required size.
• **Log Mean Temperature Difference (LMTD)**: Sizing calculations use the LMTD based on temperature profiles. Counter-flow offers higher LMTD, resulting in shorter pipe lengths.
A double-pipe heat exchanger consists of one pipe concentrically placed inside another pipe of larger diameter. One fluid flows through the inner pipe, while the other flows through the annular space between them.
Key Sizing Principles:
• **Clean vs Fouled Condition**: Over time, scale and deposit layers build up on pipe surfaces. This fouling resistance decreases heat transfer rate. Designing with fouling factors ($R_f$) ensures the exchanger performs adequately over its operating life.
• **Convection Coefficients ($h_i, h_o$)**: The convective resistance depends heavily on flow velocities, fluid viscosities, and turbulence. Higher coefficients reduce required size.
• **Log Mean Temperature Difference (LMTD)**: Sizing calculations use the LMTD based on temperature profiles. Counter-flow offers higher LMTD, resulting in shorter pipe lengths.