- DHX sits at bottom of metal lid
- Arrangement on plate for modularity
- Large radius elbows for DRACS loop to allow for flexible inspection instruments to be inserted
- DHX to TCHX centerlines will be ~6m, which is a distortion compared to scaling from CIET (would be ~8.5m)
- Each DHX should remove 2% of nominal power. 2/3 failure logic.
- Level difference between two hot leg penetrations in hot well creates a seal loop. 0.5m of head can be accommodated if isolation valve fails.
- Look at calculation for hot well height required above penetrations for thermal expansion (600°C to maximum accident condition temperature) + level swell from pump operation.
Reactor cavity cover – refueling deck hatches
- Need to have a center circular hatch to pull out center reflector
- Hatch for reactor vessel
- Hatches for 3 DRACS (see picture)
- Seal for DRACS hatch could be integrated in frame design of DRACS
- Because of high number of penetrations in cover, may need to have it be steel
- Missile shield above has fewer penetrations and could be concrete
- Design objective: 2.0 m of head from cold leg to hot leg (level swell in cold leg standpipe)
- May need full 2.0 m available inside reactor vessel to accommodate full level swell (therefore need to increase vessel height to 13 m), although probably lower because the level swell in the control rod insertion channels doesn’t take head losses from cold leg and downcomer
- If reactor vessel’s height increases by 1 m, control rod drive must be even longer (top must remain uncovered) (see picture)