José Manuel Requena Plens

Universitat Politècnica de València | UPV · Higher Polytechnic School of Gandia

This work presents the prediction of noise generated during the launch of space rockets. A semi- empirical model was applied, using as input data the physical and geometric characteristics of the jet of gases propelled by the rocket, which acts as the primary source of noise. The model is based on the one originally proposed by Eldred back in 1971...

Sound diffusers are structured surfaces designed to control the scattering of acoustic waves, mainly used in room acoustics to improve sound quality. However, as they are mainly based on quarter-wavelength resonators, phase-grating diffusers result in heavy and thick structures. We present a novel approach to design deep-subwavelength sound diffuse...

Los difusores acústicos tradicionales están basados en resonadores de cuarto de longitud de onda construidos con paneles ranurados. Es por ello que dichos paneles difícilmente pueden ser fabricados para trabajar en bajas frecuencias debido al elevado espesor resultante. Recientemente se ha propuesto el uso de metamateriales resonantes basados en re...

LoVE BASS is a tool developed for use in Matlab for the generation of vented enclosure woofer parameters. Given the target performance of the desired enclosure, two different approaches are considered. One approach searches for suitable drivers within a database. The other aims at defining the goal parameters to manufacture a custom driver. Either...

ABSTRACT In this paper, we address again the relationship between useful (0-50ms) and harmful (50ms- infinity) fields. "In situ" measurements are made of two rectangular-shaped enclosures whose dimensions are different in order to prevent the results from being determined by size. The intention of our study is to validate the experimental results a...

Actualización: Estudio realizado solo para recintos rectangulares, la validez de los resultados se mantiene solo en este tipo de recintos. ABSTRACT The theoretical calculation of the direct, early and late fields has been a matter of analysis by many authors. This project is based on the Barron and Lee (1988) theories, and the Sato and Bradley (20...

Este trabajo describe el procedimiento experimental llevado a cabo para estudiar el comportamiento radiante de la superficie de la base de estructuras en forma semilcilindro de 50 cm de diámetro y una superficie lateral de 15 cm de altura cuando son excitados mediante un actuador en el centro de la base. El nivel de vibración ha evaluado mediante a...

Link: http://hdl.handle.net/10045/77578 - La división entre campo directo y campo reverberante es correcta aunque en la práctica carece de utilidad, debido a que la fisiología del oído humano agrupa el campo directo y algunas de las primeras reflexiones haciendo creer a nuestro cerebro que todo ello constituye un solo sonido. Este concepto fue de...

Based on the results obtained in previous works, the study of the phenomenon from the point of view of the simulation in a three-dimensional model is proposed. It is verified that there is an evident parallelism between the results of the simulation and the experimental one. To delve into the question the procedure is applied in a smaller enclosure...