The importance of source type on the assessment of noise barriers

A two-dimensional (2-D) boundary element method is used to compute the efficiency of noise barriers in attenuating traffic noise. Different types of source are considered. Point sources and incoherent line sources can be introduced as results of a post-treatment of the 2-D pressure field. The insertion loss of barriers is significantly reduced in the case of more realistic incoherent line sources, as compared to that of coherent line sources. However, the relative efficiency of tops added to a straight barrier is higher. (C) 1999 Academic Press.