Goals of this meeting: Develop a power usage reduction strategy and plan related CFS (FNAL) engineering work for the next 8 weeks (up to the Valencia meeting).
What sets the service tunnel temperature? What sets the beam tunnel temperature? Modelling to be done in 3 weeks by FNAL PPT mechanical (Wands). This isthe group who did the Nummi tunnel modelling. Osha limitations on the type of work people do in given environments. Is the service tunnel work'heavy' per their rules? Should our goal be to make the environment such that there are no work restrictions? Should we be concerned at this stage withthe installation phase of the project (no - this meeting is to address operating power requirements). Can zoning be used to limit the cost of tunnel air conditioning? (no - it seems that there should be circulation of some sort). Approximately 16 MW is used for dehumidifying the service tunnel input air. POwer requirements are also listed for the periodic (1/3 RF units) dehumidifiers in the beam tunnel. In the Vancouver model, the tunnel in the service tunnel is fed through one linac shaft and removed from the adjacent one(s). The beam tunnel is sealed, so all of the humidity is from equipment water leaks or ground water. The model does not include 'recirculation'. This is what is done in the HERA and PETRA tunnels. Friday Wilhelm will tell us the power requirements are (also those expected for XFEL) The single tunnel does not allow for simple recirculation schemes. We considered alternative schemes where the air passes first through the service tunnel and subsequently through the beam tunnel in a sort of single pass system. This may allow a reduction of the beam tunnel dehumidifiers. The total planned air velocity is 1 MpH (88 feet / minute ... 20000cubic feet / minute). There was a general consensus that the target humidity is between 30 and 40%. 40 % is achieved in HERA. This corresponds to a dew point of 50 degrees F. It is reported that higher levels of humidity cause concrete and infrastructure corrosion. All of the planned sites (except perhaps the proposed CERN site) would require dehumidfiers. Issues associated with closed-circuit air systems: radiation (in the form of radionuclides), fire (pressure difference between the 2 tunnels), and cryogenic safety (ODH).
There are minutes attached to this event.