In collaboration with 16 musicians from the Minnesota Orchestra, we assess the airflow and particle concentration emitted from ten wind instruments under realistic performance conditions. Anemometer and schlieren measurement techniques are used to quantify the air flow, and aerodynamic particle sizer, laser sheet, and digital inline holography techniques are used to measure the particle concentration. The regions where the flow speed and particle concentrations are above the measurable background level vary among instruments depending on both air flow generation and particle production, but extend no farther than 30 cm from the instrument outlet for all instruments. Farther away, the upward-moving thermal plume generated by the temperature difference between the human body and ambient air is the dominant source of flow and aerosol transport. Brass instrument air flow increases with music amplitude and particle concentration exhibits an inverse response to note duration. Woodwinds emit more particles when note pitch increases. Covering the trumpet bell with one layer of acoustic fabric reduces the emitted particle concentration by ~60% with little impact on the sound quality. Adding more mask layers blocks more particles, but impedes performance and lowers the sound quality at higher frequencies (>1000 Hz). Computational fluid dynamics simulations initialized with experimental data show that placing an air cleaner above the instrument outlet can reduce the particle concentration by 90% due to the thermal plume driving aerosols upwards. Filtration efficiency further increases considerably (~10%) when lowering the ambient temperature from 25 °C to 20 °C to enhance the temperature difference with the human body.

我们与明尼苏达州乐团的16位音乐家合作，评估了在实际演奏条件下从十支管乐器发出的气流和颗粒浓度。风速计和schlieren测量技术用于量化气流，而空气动力学粒度仪，激光片和数字在线全息技术则用于测量颗粒浓度。流速和颗粒物浓度高于可测量的背景水平的区域在仪器之间会有所不同，具体取决于气流的产生和颗粒物的产生，但是对于所有仪器，其距离仪器出口的距离不得超过30厘米。更远的地方，由人体与周围空气之间的温度差产生的向上移动的热羽是流动和气溶胶输送的主要来源。铜管乐器的空气流量随音乐振幅的增加而增加，并且颗粒浓度对音符持续时间呈反比响应。当音高增加时，木管乐器会发出更多的粒子。用一层声学织物覆盖小号钟可使发出的颗粒浓度降低约60％，而对音质的影响很小。添加更多的遮罩层会阻止更多的粒子，但会妨碍性能并降低较高频率（> 1000 Hz）时的声音质量。用实验数据初始化的计算流体动力学模拟表明，由于热羽向上推动了气溶胶，在仪器出口上方放置空气滤清器可以使颗粒浓度降低90％。