Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 1 Design, Manufacture, Transport and Integration on-site in Chile of ALMA Antennas FEM Structure Distortion Analysis PM# April 2006

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 2 FEM Mechanical Model  FEM ANSYS translation into MSC.NASTRAN model  Translation procedure definition  Definition of features required by MSC.NASTRAN analyses  Modification and updating in accordance with EIE specifications

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 3 FEM Mechanical Model  MSC.NASTRAN model obtained from ANSYS model in several antenna conf.s  Locals CSs defintion  Rotation of Elevation structure(Cabin, BUS, Reflector, Apex)  Azimuth rotation conf.s in progress 0° Azimuth - 0° Elevation 0° Azimuth - 90° Elevation 0° Azimuth - 45° Elevation

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 4 FEM Mechanical Model – Gravity Deformation analysis  4 ANALYSIS CASES of self-weight  Azimuth 0°, Elevation 0°  Azimuth 0°, Elevation 45°  Azimuth 0°, Elevation 60°  Azimuth 0°, Elevation 90 ° Deformation under gravity load Azimuth 0°, Elevation 0° Deformation under gravity load Azimuth 0°, Elevation 45° Deformation under gravity load Azimuth 0°, Elevation 60°

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 5 FEM Mechanical Model – Wind Deformation Analysis  Mapping of FLUENT Pressure into NASTRAN FEM with Hypermesh DLM STRUCTURAL MODEL CFD MODEL

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 6 FEM Mechanical Model – Wind Deformation Analysis  3 ANALYSIS CASES  Az 0°, El 0°- Primary Cond. Night Time  Az 0°, El 60°- Primary Cond. Night Time  Az 0°, El 90°- Primary Cond. Night Time Deformation under wind load Azimuth 0°, Elevation 0° Deformation under wind load Azimuth 0°, Elevation 60° Deformation under wind load Azimuth 0°, Elevation 90°

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 7 FEM Mechanical Model – Thermal Deformation Analysis  Mapping of THERMICA/ESATAN Temperature into NASTRAN FEM THERMAL MODEL STRUCTURAL MODEL

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 8 FEM Mechanical Model - Thermal Deformation Analysis  6 ANALYSIS CASES  Max temp diff. Hot 1  Max temp diff. Cold 1  Max temp gradient Y Deformation under thermal load Max temp diff. Hot 1 Deformation under thermal load Max temp diff. Hot  Max temp gradient Z  Max temp gradient X  Max temp diff. Hot 2

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 9 FEM Mechanical Model – Error Budget Input  Displacements and Rotations of reference points ERROR BUDGET 2 reference points 192 reference points 604 reference points BUS Parabola Metrology Points Subreflector 3 addittional points METROLOGY

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 10 Structural FE ANSYS Model Deformation FE NASTRANModel FEM Deformation Analysis ERROR BUDGET Input Input Wind Analysis (FLUENT) Thermal Analysis (THERMICA/ESATAN) Interfacing Tools Pressures Temperatures Displacements Translation FEM Mechanical Model  Deformation Analysis Flow

Reproduction interdite © ALMA EUROPEAN CONSORTIUM Reproduction forbidden Design, Manufacture, Transport and Integration in Chile of ALMA Antennas Page 11 FEM Mechanical Model CONCLUSIONS  FE ANSYS model of ALMA Antenna has been translated in NASTRAN format by definition of a translation procedure.  Accuracy and performances of NASTRAN model have been compared to ANSYS model getting good agreement.  Interfacing tools between different kind of analysis have been identified and checked. Final adjustments are in progress.  Deformation analyses for all different kind of load have been performed by using NASTRAN global FEM.  Input data for Error Budget definition have been carried out.