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In this paper, different sort of façades have been analyzed considering their thermal behavior along a 24 hours period. A numerical model has been developed and compared with experimental measurements considering two different façades for buildings: on the one side an opaque multilayer façade; and on the other side, a ventilated façade. The numerical model representing the temperature in every layer of the façades has been successfully validated. This model has been used for determining the thermal behavior of two new ventilated façades in which the thermal mass has been changed, observing then than the existence of the moving in the air gap affects particularly the air temperature and the thermal transmittance of the façade when the sun is incising over the façade, leading to a decrease of transmittance close to 30% along the air chamber. This quantification is fundamental in warm climates, where this effect is determinant for decreasing the cooling necessities of buildings in summer with no need of increasing the mass of the façade.

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An investigation was conducted at the NASA Glenn Research Center using a set of three round jets operating under unheated subsonic conditions to address the question: "How close is too close?" Although sound sources are distributed at various distances throughout a jet plume downstream of the nozzle exit, at great distances from the nozzle the sound will appear to emanate from a point and the inverse-square law can be properly applied. Examination of normalized sound spectra at different distances from a jet, from experiments and from computational tools, established the required minimum distance for valid far-field measurements of the sound from subsonic round jets. Experimental data were acquired in the Aeroacoustic Propulsion Laboratory at the NASA Glenn Research Center. The WIND computer program solved the Reynolds-Averaged Navier-Stokes equations for aerodynamic computations; the MGBK jet-noise prediction computer code was used to predict the sound pressure levels. Results from both the experiments and the analytical exercises indicated that while the shortest measurement arc (with radius ~8 nozzle diameters) was already in the geometric far field for high-frequency sound (Strouhal number >5), low-frequency sound (Strouhal number <0.2) reached the geometric far field at a measurement radius of at least 50 nozzle diameters because of its extended source distribution. © 2005 Institute of Noise Control Engineering.