Experiences with CO 2 cooling hardware and applied designs. Experiences from past CO 2 systems and philosophies for the future. Bart Verlaat Nikhef CO 2 Kick-off meeting 9July 2009 @ Nikhef. Scope of the presentation.
PED classification for CO2 systems.
MDP = Relieve pressure > (P @ TenvMax + 5 bar(start-up) + dPpump)x110%
PTP = 1.3 x MDP
MDP = Maximum design pressure, PTP = Proof Test Pressure
24ºC => (63 bar + 5bar +10bar)x110% = 86 bar => MDP= 90 bar => PTP = 120 bar
Components with non dangerous gasses
Tubing with non dangerous gasses
0.55 2.2 11.1 33.3
32 100 250
Electrical Control replaces manual knob
Lewa pump in LHCb
Cooling spiral for pressure decrease
Thermo siphon heater for pressure increase
Accumulator Liquid level
Over critical filling
Under critical filling2PACL filling
Decrease heater power near critical point to prevent dry-out. Higher vapor density cause less convection.