一种用于消声室校准计算反平方律声压级的新方法

消声室声学性能评价是通过比较室内声源空间衰减的声压级与满足反平方律声压级差值来确定的。参考采用ISO 3745的JJF 1147-2006《消声室和半消声室声学特性校准规范》在确定满足反平方律声压级的方法上却存在明显缺陷,导致不合理的测量结果。对所出现原因进行了深入分析并通过数学推导提出了新的计算方法。

New Method on Estimation of Sound Pressure Level Based the Inverse Law in Anechoic Room Calibration

The performance of an anechoic room is assessed by comparing the spatial decrease of sound pressure emitted from a test source with the decrease of sound pressure with distance from the source according the inverse square law that would occur in true anechoic. Adopting by reference of ISO 3745, JJF 1147-2006 calibration specification for acoustic performance of anechoic rooms and hemi-anechoic rooms, it was found that some defects on its proposed estimation method on determining sound pressure level based the inverse law and causes some unreasonable measurement results. The reasons and proposed a new estimation method by mathematic deduction are analyzed.