Cadna/Ais a simple and easy-to-use software solution for calcu-lating,evaluating,precicting, and displaying noise pollution and air pollution. The software is based on technicalguidelines such as ISO9613 and Chinese HJ2.4-2009 as the calculation principle,and is suiable for predicting, evaluating, designing, and researching various noise sources.Cadna/A has the characteris-tics of easy use and strong targeting, so it is basically the first choice for users. Ithas been widely usedin noise projects such as green buildings, industrial plants, substations, transportation (highways/railways/airports) environmental assesments, and urban planning.

Due to the fact that most of the actual projects involve outdoor noise, it is difficult to conduct manualcalculation and analysis considering complex situations such as ground absorption, air attenuation,floor reflection,green belt absorption,and obstacle shielding. Therefore, in order to better evaluate the impact of noisepropagaton and predicthe noise reduction efect ofnoise control measures, it is necessary to use professional acoustic simulation software to predict and analyze the project engineer-ingin order to more accurately determine the noise reduction effect after treatment and precisely control costinvestment.

Software Computer Science

The calculation of noise is completely in accordance with ISO 9613-1 acoustics attenuation_of_sound during propagation outdoor partl and ISO 9613-2 Attenuation of sound during propagation outdoors General method of calculation Standard execution. Simulation mechanism.

Software simulation mechanism

The application of Cadna A software in pollution source noise control is mainly achieved through the following steps:

(1) Establish a threedimensional geometric model of the actual pollution source, inputing the geometric parameters ofthe building thesound powerleveland directionadltyofthesound source,terain parame-ters, other obstacle parameters, meteorological conditions, the calculation range of the sound field, and the spatial location of environmental noise sensitive pointsinto the model;

(2) Analyze and calculate the outdoor sound field, provide calculation results and outdoor sound field simulation graphics;

(3)Usingan expertsystem in the sofware to analze the noisecontibution values ofeach noise soure at various environmental noise sensitive points, determine the number of sound sources that causethe noise at the environmental noise sensitive points to exceed the standard, and determine the noise control target values for these sound sources.