Reproducing the Velador Experiment

Home Experiment Goals FAQ Theoretical Thermal Refraction Measuring Thermal Refraction Lateral Beam Deflection Vertical Beam Deflection Measuring Beam Deflection Optimum Beam Section Laser Camera Support Beam Mount Filter Camera & Laser Cells Components Experimental Controls Cell Installation Assembly Photos Calibration Photos Measuring the Images False Signal Simulation Phase 1 Experimental Procedure My First Trial Speculation for Phase 1 Trial 4 Trial 6 Trial 8 Dr. Osadchey's 6-11-07 Trial Trial 9 Trial 10 Trial 11 Trial 12 Trial 13 Trial 14 Trial 15 Trial 16 Conclusions for Phase 1 Trial 18 Trial 21 Trial 22 Trial 23 Trial 24 Dr. Osadchey's 11-5-07 Trial Trial 25 Trial 26 Trial 27 Trial 28 Trial 29 Trial 30 Dr. Osadchey's 12/9/07 Trials Trial 31 Trial 32 Trial 33 Results for Phase 1-B Sidereal Index Links More Links Speculation for Phase 2 Trial 34 Trial 35 Trial 36 Trial 37 Trial 39 Trial 40 Trial 41 Trial 42 Trial 43 Trial 44 Trial 45 Trial 46 Trial 47 Trial 48 Trial 50 Trial 51 Trial 52 Trial 53 Trial 54 Trial 55 Trial 56 Trial 57 Trial 58 Trial 59 Trial 60 (Denham Springs, LA) Trial 63 Trial 64A Trial 65A Trial 65B Custom Rich-Text Page Custom Rich-Text Page

Optimizing Support Beam Section

Further refinement of the beam design can be obtained by optimizing for the highest second moment of inertia which allows central mounting of instrumentation. Three cross-section arrangements were considered, and analyzed using equation 6.

Dimensions have been chosen to correspond to the use of 1”x6” lumber. Configurations 2 and 3 have a lower second moment of inertia than configuration 1, with approximately the same mass. Configuration 1 should be employed.

A shorter beam is desirable, as it reduces lateral deflection and is easier to mount. However, this should reduce the observed drift by 10% for every 0.3 m reduction (according to Osadchey’s working model). For this reason, nothing shorter than 2.45m (8ft) can be recommended. Shortening the support beam has no effect on thermal deformation, pro or con, but shortening the beam 20% reduces its self-weight deflection by 48%, increasing its allowed angle. A 2.45 m beam will also fit in more workspaces.