NASA Scientific and Technical Aerospace Reports

to probe the flaws in a laminate structure, and with potential application to the large area disbond and crack inspection.
Derived from text
Cracks; Delaminating; Inspection; Laminates; Structural Failure; Acoustic Propagation
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ACOUSTICS
Includes sound generation, transmission, and attenuation. For noise pollution see 45 Environment Pollution. For aircraft noise see also
02 Aerodynamics and 07 Aircraft Propulsion and Power.
20040111191 Building and Construction Research TNO, Delft, Netherlands
Underwater Shock: Combined Gas Bubble and Shock Wave Calculations
Bos, J.; March 2004; 66 pp.; In English
Contract(s)/Grant(s): A01/KM/117; TNO Proj. 006.38107
Report No.(s): TD-2004-0104; Rept-2004-CMC-R014; Copyright; Avail: Other Sources
In this report the possibility for a combined calculation of the shock wave and the gas bubble pulsation load on ship after
an un&rwater explosion is investigated The calculation of combined 3D gas/liquid problems is not (yet) feasible due to the
excessive amount of required CPU times. At the most 2D gas/liquid problems are feasible. The pressure wave, followed by
the pressures (with seamless transition) from gas bubble motion are feasible to implement
Author
Underwater Acoustics; Computation; Shock Waves; Explosions; Bubbles
20040111194 Institute TNO of Applied Physics, Delft, Netherlands
BATSOFT: Program Review and User Manual
vanBeek, P. J. G.; deJong, C. A. F.; December 17, 2003; 28 pp.; In English
Contract(s)/Grant(s): A02/KM/124; TNO Proj. 008.04410/01.01
Report No.(s): TD-0202; DGT-RPT-020140; Copyright; Avail: Other Sources
As part of the development of prediction models for the underwater acoustic signature of ships, analytical models and
descriptions are developed in order to describe the structure-borne noise transmission from operating machines to ship
foundation structures. This transmission consists of two main parts, which are the vibrating machine (’source’) and the
foundation (’receiver’). The computer program BATSOFT has been developed, in which the various mobility components of
the foundation can be calculated. The model of the foundation consists of a local seating structure and a global ship structure
(i.e. double bottom or deck). Detailed models of the local structure are coupled with statistical models of the global structure
in order to calculate the driving point mobility matrix on top of the seating. The real part of the complex mobility, together
with the magnitude of the vibratory force generated by the source, determines the amount of acoustic power that is transmitted
to the foundation. The force that can be generated and the effectiveness of resilient mounts are dependent on the magnitude
of the mobility. The main objective of BATSOFT is to be able to make quick parameter studies of the acoustic quality of
foundation structures in an early design stage. For more detailed calculations, a ‘HYBRID BATSOFT’ variant has been
developed in which detailed Finite Element Models of the local seating structures are combined with the statistical models for
the ship structure. This report describes the latest, totally revisited version of BATSOFT and serves as a manual for practical
applications i.e. calculations. Also, the structure of this version of the program is clarified, which gives understanding and can
be a basis for further development and implementation.
Author (revised)
Acoustic Properties; Computer Programs; Ships; Underwater Acoustics; Structural Analysis
20040111197 Physics and Electronics Lab. TNO, The Hague, Netherlands
Instrumented Prodder: Results from the Tests under Controlled Conditions
Schoolderman, A. J.; vanDijk, S. G. M.; Deurloo, D.; February 2004; 174 pp.; In English
Contract(s)/Grant(s): A02/KL/638; TNO Proj. 015.31580
Report No.(s): TD-2003-0070; FEL-03-A101; Copyright; Avail: CASI; A08, Hardcopy
The present report is the first status report written under the framework of the project ‘Smart prodder product development
path, phase A’. The tests under controlled conditions of the technology demonstrator version of the-Instrumented Prodder are
the main topic of this report. However, in Chapter 2 the establishment of the usergroup as well as discussions with the
demining community on the utility of a device such as the Instrumented Prodder in demining operations are reported. The
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