1 / 13

PLATO - TOU Thermal analyses

PLATO - TOU Thermal analyses. Summary of previous thermal analyses performed in 2010-2011 S.Basso – F. Borsa (I.N.A.F. – Osservatorio Astronomico di Brera ) . FE Model description : elements description. 3 element types are used, SOLID70 and LINK33 ( Ansys software). 3 Bipods

raine
Download Presentation

PLATO - TOU Thermal analyses

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. PLATO - TOU Thermal analyses Summary of previous thermal analyses performed in 2010-2011 S.Basso – F. Borsa (I.N.A.F. – OsservatorioAstronomico di Brera) S.Basso - INAF OABrera

  2. FE Modeldescription:elementsdescription • 3 element types are used, SOLID70 and LINK33 (Ansys software) 3 Bipods (link element) • 12 points • metallic ring • 3 points • ~10000 nodes • ~8000 elements S.Basso - INAF OABrera

  3. PLATO - TOU Baffleheight Configuration 1&4 Configuration 2&3 The height of the baffle for configuration 2&3 is set to obtain the sameavarage temperature for the twoconfiguration Conf.1&4: Minimum possibleheight S.Basso - INAF OABrera

  4. FE Model results:Conf. 1&4 Heaters OFF, insulating links Baffle/tube (0.0296 W/K) , no IR coating on the Window and baffle emiss.=0.94 Verycloseto the -90°C (goal) S.Basso - INAF OABrera

  5. FE Model results:Conf. 2&3 Heaters OFF, no IR coating on the Window and baffle emiss.=0.94 Verycloseto the -90°C (goal) S.Basso - INAF OABrera

  6. FE Modelresults:Fast TOU Heaters OFF, no IR coating on the Window and baffle emiss.=0.94 The Titaniumbaffleisnotnecessarytoreach the goal (-90°C) S.Basso - INAF OABrera

  7. Washers FE Model results:Baffle-tube connection Baffle-tube connection S.Basso - INAF OABrera

  8. FE Model results:Last change The intermediate value of 0.0071 W/K per bipod corresponds to the value computed with the mechanical design proposed in PLATO.LAM.SYS.SPE.1065 - Issue 2 S.Basso - INAF OABrera

  9. FE Model results:termo-elastic analyses Evaluation of thermo-elasticdeformations of telescopes Thermalanalysis Structuralanalysis Model from 20°C to low temperature S.Basso - INAF OABrera

  10. FE Model results:termo-elastic analyses • Compression of lenses L1 • Compression of tube & baffle ~ -106°C • Vertical displacement temperature ~ -102°C L6 S.Basso - INAF OABrera

  11. FE Modelresults:Thermo-elasticforconf. 1&4 The presence of the baffle creates an asimmetry window: 10.140 arcsec L1: 0.058 arcsec Check for tilt of lenses S.Basso - INAF OABrera

  12. FE Modelresults:Thermo-elasticforconf. 1&4 • The thermo-elastic model is OK Tilt up to 25 arcsec do notinfluence High dependencefrom the baffle material S.Basso - INAF OABrera

  13. FE Model results:Conclusion • The new analyses show that the latest change in the I/F parameter move away from the goal to reach -90°C in the TRP (Temperature Reference Point) with the heaters off. The greater effect is the decrease of the CSS temperature from -10°C to -63°C. • In order to increase again the TRP Temperature to the goal the possibility are: • Increase the heaters power adding 1W for the normal TOU and 0.2W for the fast TOU. That means that the total heater power would increase of 32*1+2*0.2= 32.4W • Reducing the decoupling between the Camera I/F plane building bipods more conductive. This solution would increase the uncertainty in the mean temperature of the telescopes because the temperature of the Camera I/F plane is less known. • Adopt not conventional approaches like: • titanium baffle, • thermal filters • coating or layer on the internal surface of the baffle to reduce the internal emissivity S.Basso - INAF OABrera

More Related