This paper pertains to the feasibility analysis of a magnetohydrodynamic (MHD) inductive generator coupled with a Thermo Acoustic (TA) resonator. The MHD and TA processes have the great advantage to convert energy without mechanical moving components. In this work, first, the design criteria are given, then the order of magnitude of the obtained parameters is used to model the system by using the finite element method (FEM) to confirm the theoretical results. The conceptual idea and the FEM model are described. Energy conversion process.The TA phenomenon occurs when a great gradient of temperature is present in the longitudinal direction of a duct containing

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The aim of this chapter is to show the potentiality of a novel approach to ultrasonic investigation of masonry structures. In order to obtain useful, rapid and relatively low cost informations, the ultrasonic “Direct Transmission Technique” is applied on the structure under exam. This technique uses a beam of ultrasonic waves emitted by a transducer and received by another one placed on the opposite surface of the structure. The waves pass through the (ample under test) and are reflected and refracted by incidental discontinuities encountered along the path. The characteristics of the ultrasonic vibration are then investigated in order to obtain interesting information on the conditions of the materials. In particular, the attention has been focused on the correlation between the average density of the ray paths and the characteristics of acquired signals. This feature has been extracted from signals obtained by direct measurements on a real stone masonry with a known internal cavity. Then measurements have been related to the known geometry to verify the actual correlation with the characteristics of the traversed paths