In this paper, a design methodology is proposed, wherein tools and knowledge from the areas of structural design, numerical optimization, and noise, vibration and harshness (NVH) engineering are combined into a single toolbox for vehicle design. The methodology attempts to address the topic of sustainable development from both economic and environmental perspectives within the vehicle industry. A brief review of the topics of NVH and numerical optimization is given for the purposes of disseminating knowledge. Finite element codes for predicting structural and acoustic response are implemented within the iterative design methodology, which is explained for generic problems. Specific focus is placed on the need for understanding functional requirements of the entire system rather than its components. The methodology is implemented in an automotive case study. The results in terms of design solution and development framework are evaluated and discussed. As part of this evaluation, and integral to the design process, an acoustic sensitivity analysis of the final solution is performed and the results are presented.

This contribution presents preliminary data on the petrographic and mineral—chemical composition of the granitoid and dioritoid core samples of the Itatsky and Kamenny sites in the Nizhnekansky Massif of the Krasnoyarsk Region, in combination with data on structure of their pore space, filtration, elastic, mechanical and thermophysical properties, data necessary to select a site for an underground research laboratory. This laboratory would be a precursor to an underground radioactive waste facility. It was found that the variation of petrophysical properties depends on the degree of metamorphic, hydrothermal—metasomatic and deformational transformations, and differs markedly for two groups of rocks, namely, 1 — granites and granite-gneisses, and 2 — quartz diorites and diorites. Comparative analysis of the data obtained shows that the country rocks of the Kamenny site have a relatively higher degree of heterogeneity in their petrophysical characteristics, than those of the Itatsky site. These results could be applied both to select the preferred site and to make a preliminary estimate of the thermal, hydraulic and mechanical behaviour of country rocks in the vicinity of a prospective underground heat-generating waste repository.

Lightweight porous acoustic multilayer trim components have traditionally been specified in terms of sound absorption and sound transmission loss performance targets. Importantly, the material specification of the trim component developed only for absorption and sound transmission loss may be suboptimal in terms of, e.g., sound radiation behavior. This highlights the necessity for accurate, computationally efficient, and robust simulation method, which should form an integral part of a multidisciplinary optimization tool. In addition, for such optimization to be physically meaningful the design parameters used should be based on relations between microstructural dimensions and properties, and the corresponding macroscopic parameters describing porous materials. This paper discusses recent results from research focused on the parametrization of porous foams, i.e., continuous links between micro-dimensions, elasticity, density, and flow resistivity, used in higher order 3-D finite element simulations of multilayer components for structural-acoustic applications. In addition to the microdimensions, also the thicknesses of individual layers have been used as design parameters, with the overall weight as the design objective. Acoustic and vibration targets, velocity of the radiating surface, radiation efficiency, transmission, etc., as well as upper and lower bounds of the microdimensions, have been used as constraints.

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