Power Plant Β· Flow
Condenser Cooling-Water Flow
Cooling-water flow required to condense a given turbine exhaust flow, from the steam-side heat load (IF97 wet-steam enthalpy) and the water-side enthalpy rise, with terminal temperature difference, LMTD and water-to-steam ratio.
Verified against published standard
Condenser data
Typically 0.88β0.94 for a condensing turbine exhaust.
Leave empty for saturated condensate (no subcooling).
Enter the inputs and press Calculate.
About This Calculation
Cooling-water flow for a surface condenser is set by the heat that must be removed from the exhaust steam and the allowable water temperature rise. Exact IF97 enthalpies are used for wet steam, condensate and cooling water, and TTD, LMTD and water-to-steam ratio are reported for performance checks.
Frequently Asked Questions
What is a typical water-to-steam ratio?
Roughly 50β70 kg of cooling water per kg of exhaust steam for a once-through condenser; compare your result with design.
Why does a smaller TTD need more water?
For a fixed duty a smaller approach requires a larger heat-transfer area or a lower water temperature rise, i.e. more flow.
Why is the exhaust dryness around 0.9?
As steam expands through the last turbine stages it partly condenses, so exhaust steam is a wet mixture. A dryness fraction of roughly 0.88 to 0.94 is typical; the exact value comes from the turbine heat balance.
Does the flow include seawater or brackish cooling water?
The enthalpy values are for pure water. Seawater has a slightly lower specific heat, so the flow needed for the same temperature rise is a few percent higher; scale the result by the specific-heat ratio for your water.