CRIPTE

CRIPTE

Product by :logo_CRIPTE

ONERA

 

Scope :

CRIPTE is used to study multiconductor transmission line networks stressed with different kinds of sources such as voltage or current generators, electromagnetic fields. Cables can be very complex, they can be shielded or not, dielectric insulators can be taken into account.

 

Features :

CRIPTE (in French “Calcul sur Réseaux des Interactions Perturbatrices en Topologie Electromagnétique”) is a set of programs allowing computation of propagation and electromagnetic coupling on multiconductor cable networks.

This software, developed by ONERA since 1990, is based on the Electromagnetic Topology formalism initially proposed by C.E. Baum [1] to whom the CRIPTE logo is dedicated. Electromagnetic Topology is a method which enables to handle electromagnetic coupling problems on a complex structure. Its originality consists in splitting the whole system into several sub-systems that can be solved locally and independently from each other [2].

The key equation of this network theory is the Baum-Liu-Tesche (BLT) equation. The multiconductor transmission lines networks formalism is the most direct application of this theory.

CRIPTE is made of 2 main modules:

  •  The CRIPTE editor module
  •  The CRIPTE computational module

 The CRIPTE editor module is a tool with a graphical human interface (GUI) implemented with Motif/X11 libraries. It enables creation/modification of cable networks from their topological description up to the definition of run parameters. It also proposes various tools to create tubes files (described by cable lumped electrical parameters), junctions files (S, Z or Y parameters characterizing connections or terminal loads of wires), files to create sources to apply on tubes…

 The CRIPTE computational module tool has no GUI. It is used to run BLT simulations (computation of currents/voltages along cable networks) or SEQ simulations (compaction of sub-networks as equivalent junctions and Thevenin generators). The input file (so called “batch card”) for the computation is the one generated by the CRIPTE editor module.

CRIPTE has been applied and is still applied in numerous ONERA projects. Among them, we will mention two particularly important milestones :

  • The first applications on the EMPTAC aircraft (1993-1996) which demonstrated for the first time the capability to model real complex cable-bundles in real installation configurations.

  • The HIRF-SE FP7 EU program (2008-2013) in which CRIPTE has been applied at real aircraft system level and coupled on various 3D computer solvers thanks to the HIRF SE framework.

 

The version of CRIPTE developed and distributed by ONERA is called the “Research version”. 

The main capabilities of the 6.0 version are :

  • Network creation
  • Calculation of currents and voltages at any point of a tube on one or several wires
  • Management of sparsity in the BLT matrix
  • Compaction of subnetworks (equivalent junction and equivalent Thevenin generator)
  • Calculation of the EM field emission of a cable network laying on a metallic ground plane
  • Creation of ideal junctions for perfect connection between wires and to the ground
  • Creation of junctions based on electrical circuit description with R, L, C lumped components
  • Built-in generic termination junctions in networks: short-circuit, open circuit, matched, 50 Ohms
  • Assignment of junction data files (S, Z, Y parameters)
  • Source management:

    • “E run3D” sources for EM incident fields coming from 3D calculation (Agrawal’s Field-to-TL approach),
    • “I run3D” sources for current on cable-shields calculated by a 3D code transformed as source terms (using the transfer impedance of the cable shield),
    • Lumped or localized voltage and current generators,
    • Plane wave illumination of a cable network,
  • Assignment of tube data files (per-unit-length electrical parameters and propagation parameters)
  • Zero-length tubes
  • Analytical diagonalization of tubes
  • Creation of models of cables with various numbers of cable-shields (shields considered as equivalent wires)
  • Edition of the cross section of cables with the included “LAPLACE Editor” module
  • Calculation of the per-unit-length (p-u.l) electrical parameters L and C from the cross section geometry with the included “LAPLACE Calculation” module
  • Random generation of a tube cross-section geometry with the “ALEACAB” tool
  • Various models of losses on the reference conductor (in particular, lossy soils)
  • Models of earthing systems

 

Screenshots :

 

cripte2

Figure 1: Generation of tube 2D cross-sections with CRIPTE’s ALEACAB module

 

 

 cripte3

Figure 2: CRIPTE in the CuToo framework (implementation of the GO32 test case)

 

 cripte4

 Figure 3: The CRIPTE network of the Piaggio 180 AHC system (HIRF SE)

 

 cripte5

Figure 4: Numerical validations of Field-to-Transmission-Line applications carried out on Dassault’s F7X aircraft (HIRF SE) (courtesy Dassault)

 

References :

  1. C.E. BAUM,
    The Theory of Electromagnetic Interference Control
    Interaction Notes, note no 478-December 1989.
  1. C.E. BAUM, T.K. LIU, F.M. TESCHE,
    On the analysis of general multiconductor transmission line networks
    Interaction Notes, note no 350 – November 1978.
  1. J.P. PARMANTIER,
    Approche Topologique pour l’étude des couplages électromagnétiques
    Thèse de l’Université des Sciences et Techniques de Lille Flandres Artois – décembre 1991.
  1. J.P. PARMANTIER, G. LABAUNE, J.C. ALLIOT, P. DEGAUQUE,
    Couplages électromagnétiques sur des systèmes complexes : Approche topologique
    La Recherche Aérospatiale, Année 1990 no 5, pp. 57-70.
  1. J.P. PARMANTIER, G. LABAUNE, J.C. ALLIOT, P. DEGAUQUE,
    Topologie Electromagnétique : Méthodes de caractérisation de jonctions
    La Recherche Aérospatiale, Année 1990 no 5, pp. 71-82.
  1. J.P. PARMANTIER, F. ISSAC, S. BERTUOL, F. BOULAY,
    Modèle unifié d’un câble multiconducteur blindé : application à la susceptibilité et à l’émission électromagnétique
    10eme colloque sur la CEM, Clermont-Ferrand – mars 2000.
  1. J.P. PARMANTIER, X. FERRIERES, S. BERTUOL, C.E. BAUM,
    Various ways to think of the resolution of the BLT equation with an LU technique
    Interaction Notes, note no 535 – 1998.

Contacts :

Solange Bertuol (solange[dot]bertuol[at]onera[dot]fr)

Jean-Philippe Parmantier (jean-philippe[dot]parmantier[at]onera[dot]fr)

Isabelle Junqua (isabelle[dot]junqua[at]onera[dot]fr)