Sector Shielding analysis tool (SSAT) Sector Shielding analysis tool (SSAT) Computation Automation Using UNIX Awk and Computation Automation Using UNIX Awk and MSC/NASTRAN FEM modelMSC/NASTRAN FEM model

EFACEC - October 3-7 2005

Adolfo Aguilar

2SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

OverviewOverview

Objective:– Optimized Mass for the Electronics unit– TID and Aluminium Shielding Map for PCBs– Internal radiative environment definition for the equipment– Selection of appropriate electronics for the unit– Engineering approach to reduce analysis costs

Approach– Use of programming scripts to translate from FEM information

to GEANT4 analysis– SPENVIS SHIELDOSE-2 - GEANT4 SSAT computation

3SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

HARDWARE UNDER STUDYHARDWARE UNDER STUDY

Components Technology Test Bed (CTTB)

Two Units– Control Unit

– Experiment Board (EB) Pallet Limited Mass budget EB Pallet located outside S/C Mass optimization required

4SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

ORBIT DEFINITIONORBIT DEFINITION

Orbit Location

Mission 1 GSTB-IOV

Orbit type: Walker 27/3/1+3

Apogee: 23616.00 km

Perigee: 23616.00 km

Inclination: 56.00º

R.A. Ascending Node: 120.00º

Argument of Perigee: 0.00º

Period: 14.36 hrs

Duration: 0.60 days

Number of orbits: 1.0

Orbit start: 01/01/2006 00:00: 0.0

Orbit end: 01/01/2006 14:21:18.4

Mission end: 31/12/2010 00:00: 0.0

Mission length: 1825.00 days (5.00 years)

5SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

GALILEO-IOV S/CGALILEO-IOV S/C

EB PALLET LOCATED OUSIDE S/C

6SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

RADIATION ENVIRONMENTRADIATION ENVIRONMENT

SPENVIS SHIELDOSE-2 (Al-spheres) Analysis based on GALILEO orbit too pessimistic

6 mm Al thickness for the desired TID on PCBs (50krad)

7SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

GEANT4 DRAWBACKSGEANT4 DRAWBACKS

Physicist Oriented Tool– Lack of physical models explanation– Lack of definition of applicability limits

Very time consuming tool– Geometry definition demands a lot of workload– Output Results not directly applicable for engineering use

• Too theoretical/ideal results

• Not directly applicable to front-end electronics simulation

• Lot of post-process required to be cost-effective

8SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

FEM Model A source of Analysis PointsFEM Model A source of Analysis Points

A translation from FEM to GEANT4 is possible

Each node in the FEM mode is the location of a target point for the analysis

9SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

SECTORIAL ANALYSIS (GEANT4-SSAT)SECTORIAL ANALYSIS (GEANT4-SSAT)

GEANT4 model for S/C and EB Pallet

10SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

UNIX tools to translate FEM into GEANT4UNIX tools to translate FEM into GEANT4

FEM models are ASCII based files Node and connectivity definition is defined Material and geometrical definition already coded AWK, Perl, Phyton process can automate the task Output results can be plotted using FEM postprocessors

– PATRAN

– IDEAS

11SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

Sectorial Analysis for the PCBsSectorial Analysis for the PCBs

FEM Grids used as point target for the analysis Shielding and TID map for each PCB Very Fast and Efficient Method

– From Geometry definition to post-process 3 days

12SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

Post-Processed Results using PATRANPost-Processed Results using PATRAN

TID Maps obtained for each location of the PCB 3.5 mm (30krad) Al thickness reduced the mass

13SPENVIS & GEANT4 WORKSHOPLeuven - 3-7 October

ConclussionsConclussions

GEANT4 needs a more engineering approach to be a cost effective tool for electronics/detectors design tool

Existing tools for FEM analysis can be used to optimize the analysis time

UNIX tools like AWK, Perl or Phyton can be used to translate FEM models information into GEANT4 analysis cases

Post-Process can be done using existing tools from the market like PATRAN or IDEAS.

A better understanding of the GEANT4 physical models is demanded with proper explanation of the applicability limits for better engineering use.