When a structure is irradiated by a pulsed cold X-ray with high energy density, the instantaneous deposition of energy will induce melting, vaporization, and sublimation of the outer layer of material(s). As a result, the material(s) will blow off and hence lead to a so-called blow-off impulse. This kind of impulsive load will cause high-level structural responses. In order to investigate the effects, various test simulation techniques, such as the light-initiated high explosive (LIHE) technique, the spray lead at target (SPLAT) technique and the sheet-explosive technique, were developed due to the lack of proper X-ray sources. This paper presents a rod-explosive technique developed from the sheet-explosive technique. In this technique, the main property of the explosive, i.e. the specific impulse, is determined by using a pendulum test facility. The simulation load (equivalent to the cosine-distributed specific impulse on a conical shell induced by X-ray) is designed by load discretization and impulse equivalence. Numerical simulations of structural responses to both X-ray loads and rod-explosive loads were performed for validating the test simulation technique. An application example of testing a complex structure is briefly given in the end. The rod-explosive technique has the features of low costs and rather high fidelities. It provides a new approach for testing the structural responses induced by X-ray blow-off impulses.

In space engineering, pyroshock (or pyrotechnical shock) environments induced by pyrotechnical devices are severe for space hardware, especially the inner electrical components. Thus pyroshock responses need to be well considered in the design and manufacture of a space structure or system. Because of the lack of efficient analytical technique, laboratory tests are of importance at present. This paper experimentally studies the pyroshock responses of a conical aeroshell. Two experiments were performed by ignitions of true pyrotechnical devices. A number of acceleration histories were measured and the corresponding shock response spectrums (SRSs) were analyzed. The results show that the responses, not only in time domain but also in frequency domain, have significant decaying characteristics along the axial distance from the pyroshock sources. The quantitative results provide us a good understanding of local environments for design of the components and the corresponding installations.

The computer simulation has become an important means to study fire broke out and its law of development today. Fire Dynamics Simulator is three-dimensional computational fluid dynamics software based on LES. And it is widely used in the field of fire science. However, it is rarely used in the study of forest fires. Through the study of tree morphological parameters,combined with the modeling features of the pre and post-processing graphical software PyroSIM, this article explored a tree modeling method for FDS.

In order to verify the fitting degree of whole vehicle simulation modeling and practical vibration, the transportation truck subsystem simulation models are established and the whole vehicle virtual model is assembled with ADAMS software based on multi-body dynamics theory and virtual prototyping. The documents of rural road are created in the MATLAB with harmonic superposition principle according to the description of pavements in different grades in the national standard. Through loading road documents, the obtained vibration spectrums are compared with the measured spectrums. The RMS(Root of Mean Square) of the virtual test inosculates basically with the RMS of practical running-in test in each test point by analyzing. It shows that the simulation experimental results have enough reliability and the established virtual prototyping can be used as a basis for structural design of vibration simulation system.

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