Unsteady NEWPAN : USNEWPAN
USNEWPAN highlights
- Unsteady, subsonic, inviscid flow in the frequency domain
- The governing equation now reduces to a Helmholtz type PDE
- A logical, significant advance over methods such as DLM
- Unsteady perturbations to the full NEWPAN steady solution
- Full support for standard NEWPAN features:
- thick/thin surfaces, hybrid structured/unstructured etc.
- Modelling of the effect of incidence and thickness - at
any combination of reduced frequency and (subsonic) Mach number
- Direct coupling to MSC.Nastran™ for
flutter analysis
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USNEWPAN aeroelastic analysis of a complete aircraft,
featuring the unsteady pressure coefficients at a tailplane section
throughout the modal oscillation :
see more information here
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A new, fast, practical capability for flutter analysis, gusts,
maneuvering, etc. on complex configurations
A comparison of USNEWPAN with DLM
The Doublet Lattice Method (DLM) is
still widely used in the field of aeroelasticity in order to
provide the aerodynamic solution during coupled structural
analysis. It does, however, feature a number of obvious
limitations. A large motivation during the development
of USNEWPAN was to provide a practical, more sophisticated,
successor to DLM.
USNEWPAN does not rely on the grossly linearized theory of
classical methods. Hence
the USNEWPAN implementation provides predictions for the effect of
thickness and incidence on flutter velocity - an effect not seen with
classical methods like DLM. Configurations can be modelled
accurately using the true wetted surface, to
obtain unsteady results with modest computational time - a
few seconds to a few minutes on a typical desktop.
| | DLM | USNEWPAN |
| Incidence | NO | YES |
| Camber | NO | YES |
| Twist | NO | YES |
| Thickness | NO | YES |
| Frequency domain | YES | YES |
| Subsonic | YES | YES |
| Transonic | NO | NO |
| High Lift | NO | YES |
| Runtime | FAST | FAST |
| Fuselage | slender body | YES |
| Flutter at trimmed condition | NO | YES |
| Easy experimental correction | + | ++ |
| Ease of use | ++ | + |
Running USNEWPAN
USNEWPAN may be run either:
- stand-alone, producing a set of results for each of the
principal rigid body modes, or for a specific user-defined mode; OR
- coupled to MSC.Nastran™ with results
stored directly into the Nastran database.
Please refer to the following pages for more information
and validation examples:
Dynamic Aeroelasticity: Flutter Analysis using
MSC.Nastran™
USNEWPAN Unsteady Validation: 2D
Exact Comparison.
AGARD Report No.702 (LANN wing):
USNEWPAN vs Experimental Comparison.
MSC.Nastran,MSC.Patran and MSC.Flightloads are trademarks of MSC.Software Corporation.
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