Refrigerant Capillary Tube Calculator
Single-phase friction estimate for preliminary sizing.
How to Use This Calculator
1
Provide ṁ, ρ, μ
Use saturated liquid properties at inlet if unknown.
2
Enter tube geometry
Inner diameter and roughness for copper capillary.
3
Set ΔP
Desired pressure drop from condenser outlet to evaporator inlet.
Formula
L = ΔP · D / ( f · (ρ v² / 2) )
v = ṁ / (ρ A), A = π D²/4, f from laminar (64/Re) or turbulent (Swamee–Jain) correlations.
Note: Real capillaries have two-phase flow; this is a single-phase estimate for early sizing.
Frequently Asked Questions
How accurate is this?
It provides a rough estimate. Use detailed two-phase models or manufacturer charts for design.
What refrigerant should I select?
This tool is refrigerant-agnostic; you enter ρ and μ. Use property tables (REFPROP or similar) for accurate values.