อัปเดต 2026-09-07

Minor loss / K-factor & equivalent length

Crane TP-410 vs Hooper 2-K vs Darby 3-K

Compares fitting resistance coefficient K, equivalent length, and pressure drop by three side-by-side methods: Crane's single constant, Hooper's 2-K, and Darby's 3-K.

Open the calculator

คำนวณอย่างไร

Crane TP-410 uses one Re/size-independent K per fitting from the project catalogue; Hooper (1981) and Darby (2001) add Reynolds-number and pipe-size corrections on top of the same catalogue ids.

สมการ

Hooper 2-K (Hooper, Chem. Eng. 1981)

K = \frac{K _{1}}{R e} + K_{\infty} (1 + \frac{1}{D _{in}})

D_in = nominal inside diameter in inches; K∞ = fully-turbulent coefficient

Darby 3-K (Darby, Chem. Eng. Fluid Mechanics, 2001, Table 7-3)

K = \frac{K _{1}}{R e} + K_{i} (1 + \frac{K _{d}}{D _{in}^{0.3}})

current best-practice size correction (0.3 exponent vs Hooper's 1.0); D_in in inches

Equivalent length & fitting ΔP

L_{e q} = \frac{Σ K \cdot D}{f}, Δ P = Σ K \cdot \frac{1}{2} ρ v^{2}

Darcy-basis L_eq (f = Darcy friction factor); ΔP from the summed K across the fitting set

← ฟีเจอร์ทั้งหมด