Linear Thermal Expansion
Compute elongation ΔL from CTE α, length L and ΔT.
Inputs
Formula
ΔL = α·L·ΔT
Long shafts/pipes need expansion joints or loops.
Fundamentals
Compute elongation ΔL from CTE α, length L and ΔT.
This tool computes Linear Thermal Expansion from the formula: ΔL = α·L·ΔT
History
Fluid mechanics and heat transfer were established in the 18th–19th centuries with steam engines and thermodynamics.
Engineering applications
Used for piping, heat-exchange and hydraulic system estimates.
Glossary
| CTE α | Input parameter |
| Length L | Input parameter |
| Temp diff ΔT | Input parameter |
| Elongation ΔL | Output result |
How to use
- Fill in CTE α, Length L, Temp diff ΔT in the Inputs section (watch the unit on each field).
- Click Calculate; the tool evaluates the formula shown above.
- Read Elongation ΔL in the results area.
Formula · Worked Example · Knowledge
Formula
核心计算关系：ΔL = α·L·ΔT
输入变量：
- CTE α
alpha— 1e-6/K - Length L
L— m - Temp diff ΔT
dT— K
输出结果：
- Elongation ΔL
dL— mm
假设/适用：Flow formulas assume steady, incompressible, continuous flow; correct for compressible/high-speed.
Worked Example
根据公式 ΔL = α·L·ΔT，取 CTE α = 12 1e-6/K；Length L = 2 m；Temp diff ΔT = 80 K。
代入计算得：Elongation ΔL = 1.92 mm。
Key Points
- Flow formulas assume steady, incompressible, continuous flow; correct for compressible/high-speed.
- Reynolds Re sets laminar/turbulent; friction f depends on regime & roughness.
- Energy eqn includes elevation, pressure and velocity heads; keep units as length.
Parameters
Inputs
| Parameter | Symbol | Unit | Default |
|---|---|---|---|
| CTE α (1e-6/K) | alpha | 1e-6/K | 12 |
| Length L (m) | L | m | 2 |
| Temp diff ΔT (K) | dT | K | 80 |
Outputs
| Result | Symbol | Unit |
|---|---|---|
| Elongation ΔL | dL | mm |
Applications
- Pipe flow rate and pressure drop
- Hydraulic cylinder force/speed design
- Flow-meter selection and calibration
FAQ
What formula does this tool use?
This tool computes per ISO / AGMA / ASME standard formulas: ΔL = α·L·ΔT
How accurate are the results?
Results match input precision, based on SI units and common engineering approximations; for critical duty re-check with a safety factor.
Where is it used?
Pipe flow rate and pressure drop