General aerosol Sauter mean diameter measurement for spherical and non-spherical particles based on low-complexity scattering algorithm

• Published in: Measurement : journal of the International Measurement Confederation 2024-02, Vol.226, p.114104, Article 114104
• Main Authors: Lin, Mengxue, Zhu, Ming, Liu, Huan, Chen, Yanzhe, Li, Chengkun
• Format: Article
• Language: English
• Subjects: Aerosol measurement method; Low-complexity scattering algorithm; Sauter mean diameter; Spherical and non-spherical particles
• ISSN: 0263-2241; 1873-412X
• DOI: 10.1016/j.measurement.2023.114104

•Sauter mean diameter (SMD) is a key microphysical indicator in aerosol measurement.•Proposed LCSA-model-based GASM is an aerosol SMD measurement method.•It solves problem of other methods by measuring spherical and non-spherical particles.•Ovality sensor and SMD sensor were developed to test the GASM method.•DEHS and n-heptane combustion smoke SMD measurement accuracy was 95.26% and 93.43%. Sauter mean diameter (SMD) is a key microphysical indicator in aerosol measurements that rely on optical-scattering-related methods. However, owing to the lacking clear definition of non-spherical SMD and the complexity of scattering calculations for non-spherical particles, existing SMD measurement methods are only applicable to spherical particles. A general SMD measurement method for both spherical and non-spherical aerosols is thus proposed. In this method, the shape coefficients of non-spherical particles are defined and used to calculate SMD. The scattering models for spherical and non-spherical particles are unified into a low-complexity scattering algorithm (LCSA). Based on LCSA, SMD can be measured using only two light sources of different wavelengths. Compared with SMD measurement results without considering particle shape, the accuracy of the proposed method increased by an average of 11.31% and 11.37% for unimodal and bimodal aerosols, respectively, while its accuracies for spherical and non-spherical aerosols respectively reached 95.26% and 93.43%.