What Are The Typical Operating Parameters of Hydrogen Cooler for Steam Turbine Generator

Typical operating parameters of a hydrogen cooler for a steam turbine generator are governed by generator rating, cooling duty, and plant design. The ranges below reflect common utility and industrial power plant practice.

1. Hydrogen Side (Primary Cooling Medium)

• Hydrogen pressure:
  3.0 – 6.0 bar(g)
  (Higher pressure improves heat transfer and reduces windage losses)

• Hydrogen inlet temperature:
  50 – 80 °C

• Hydrogen outlet temperature:
  40 – 65 °C

• Hydrogen purity:
  ≥ 98% (typically 98–99.9%)
  High purity is essential to maintain cooling efficiency and prevent oxidation.

• Hydrogen moisture content (dew point):
  ≤ –30 °C
  Low moisture protects insulation and metallic components.

2. Cooling Water Side (Secondary Cooling Medium)

• Cooling water inlet temperature:
  25 – 35 °C
  (May be higher in tropical climates)

• Cooling water outlet temperature rise:
  5 – 10 K

• Cooling water pressure:
  0.3 – 1.0 MPa (operating)

• Design pressure (water side):
  1.6 – 2.5 MPa
  According to ASME or PED requirements.

• Cooling water quality:
  Demineralized or treated water to prevent fouling and corrosion.

3. Thermal Performance

• Typical heat removal per cooler:
  200 – 2,000 kW, depending on generator size

• Approach temperature (H₂ to water):
  5 – 10 °C

• Cooling effectiveness:
  Designed to maintain stator and rotor temperatures within insulation class limits (Class B, F, or H).

4. Mechanical & Design Parameters

• Tube material:
  Stainless steel (SS304 / SS316L) or copper alloy

• Tube-side medium:
  Cooling water

• Shell-side medium:
  Hydrogen gas

• Leakage requirement:
  Zero hydrogen-to-water cross leakage (critical safety requirement)

5. Safety & Monitoring Parameters

• Hydrogen pressure differential (H₂ vs atmosphere):
  Always maintained positive to prevent air ingress

• Hydrogen leak detection:
  Continuous monitoring required

• Temperature monitoring points:
  Hydrogen inlet/outlet and cooling water inlet/outlet

Summary Table (Typical Values)