De Laval Turbine — Slider Calculator educational approx

Inputs

Key Results

Isentropic heat drop Δh (kJ/kg)

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Jet speed C₁ (m/s)

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Optimum tip speed u (m/s)

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Speed N (rpm)

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Shaft work wshaft (kJ/kg)

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Power P (kW)

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Outlet dryness x (–)

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Water content w = 1−x

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h₂s (kJ/kg)

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Method: Δh is estimated from an isentropic expansion using simplified steam relations (latent heat fit and ideal‑gas superheat). For design‑grade work use steam tables/IAPWS‑IF97.

Details & equations

Tsat(p) ≈ 100 + 22 ln(pbar); hf(T)≈cplT; sf(T)≈cplln(TK/273.15); L(T)≈2501−2.36(T−100); hg=hf+L; sg=sf+L/TK; Superheat: h₁≈hg(Tsat1)+cp(T₁−Tsat1), s₁≈sg(Tsat1)+cpln(T₁/Tsat1). At p₂: x=(s₁−sf2)/(sg2−sf2), h₂s=hf2+x·L₂, Δh=h₁−h₂s. Nozzle/rotor: C₁=√(2Δh·1000); C1θ=C₁cosα; uopt=C1θ/2; N=60u/(πd); wstage=Δh cos²α; wshaft=ηmech·wstage; P=ṁ·wshaft.