Results from the Qualification of the three Pre-series Test Cells for the LHC Cryogenic Distribution Line

Three pre-series test cells of the LHC cryogenic distribution line, manufactured by three European industrial companies, have been tested in the years 2000 and 2001 to qualify the design proposed and to verify the thermal and mechanical performances. The pre-series test cell, about 112 m long, consisted of a standard cell (about 107 m long) and an additional service module needed for test purposes. This paper summarises and compares the main results of the qualification tests to the requirements of the technical specification. Technical considerations on the measurement stability and corresponding overall error are also presented

Experimental Simulation of Helium Discharge into the LHC Tunnel

The LHC cryogenic system contains about 100 tons of liquid helium. The highest amount of helium is located in the magnet cold mass (about 58 tons @ 1.9 K, 0.13 MPa), in the QRL supply header C (about 26 tons @ 4.6 K, 0.36 MPa) and in the ring line (about 0.7 tons 290 K, 2 MPa). The rupture of header C is one of the failures leading to the worst scenario of helium discharge into the tunnel. To investigate the consequences of this failure an experiment has been performed. This paper presents the layout of the test set-up and compares the experimental results with calculated data

A Cryogenic Test Set-Up for the Qualification of Pre-Series Test Cells for the LHC Cryogenic Distribution Line

Three pre-series Test Cells of the LHC Cryogenic Distribution Line (QRL) [1], manufactured by three European industrial companies, will be tested in the year 2000 to qualify the design chosen and verify the thermal and mechanical performances. A dedicated test stand (170 m x 13 m) has been built for extensive testing and performance assessment of the pre-series units in parallel. They will be fed with saturated liquid helium at 4.2 K supplied by a mobile helium dewar. In addition, LN2 cooled helium will be used for cool-down and thermal shielding. For each of the three pre-series units, a set of end boxes has been designed and manufactured at CERN. This paper presents the layout of the cryogenic system for the pre-series units, the calorimetric methods as well as the results of the thermal calculation of the end box test

Using Controlled Experiments to Calibrate Computer Models: The Airplane Game as a Lean Simulation Exercise

Simulation games may be used to introduce lean principles to those who are considering implementing them. However, they can also function as controlled experiments against which to calibrate a computer model and they can even be adapted to serve as the gold standard of scientific experimentation, the randomized-controlled trial. Results generated from a live playing of the Airplane Game validate an EZStrobe computer-based simulation model representing one part of the game. Close alignment of results suggests that the computer model will likely be able to accurately predict outcomes from similarly structured, real life activities, such as those encountered in a design office or on a construction site