๐ฅ Rankine Cycle โ Regenerative (Open/Closed FWH)
Analyze regenerative Rankine steam cycles with 1 or 2 extraction stages. Compare open and closed feedwater heaters. Compute extraction fraction y, thermal efficiency, back-work ratio, and power output.
๐ Configuration
Key Equations:
ฮทth = Wnet/Qin
Open FWH: yยทhext+(1โy)ยทhfw = hf,sat
BWR = Wpump/Wturbine
Wpump = vfฮP/ฮทp
ฮทth = Wnet/Qin
Open FWH: yยทhext+(1โy)ยทhfw = hf,sat
BWR = Wpump/Wturbine
Wpump = vfฮP/ฮทp
๐ Results
Configure inputs and click Analyze to view results.
๐ Methodology
Regenerative Rankine
Extracting steam from the turbine to preheat feedwater raises average temperature of heat addition, improving thermal efficiency. Each extraction stage adds ~1โ3% efficiency gain.
Open vs Closed FWH
Open (direct contact) FWH mixes extracted steam with feedwater โ simple, effective, requires separate pump per stage. Closed (shell-tube) FWH keeps streams separate โ more complex but allows single pump.
Assumptions
- Simplified water saturation curve fits (educational).
- Isentropic efficiencies for turbine and pump.
- Saturated liquid exits each FWH.
- Steady-state, steady-flow.