一瓶茶作为通用亥姆霍兹共振器
A bottle of tea as a universal Helmholtz resonator
摘要：
共振是许多系统中普遍存在的现象。特别是，赫尔曼·冯·亥姆霍兹（Hermann von Helmholtz）在19世纪50年代研究了空腔中的空气共振。最初用作声滤波器，亥姆霍兹共振器是刚性壁腔，在给定的固定频率混响。一种可调类型的共鸣器是所谓的通用亥姆霍兹共鸣器，一种由两个滑动圆柱体组成的装置，能够产生连续频率范围内的声音。在这里，我们提出了一个简单的实验，使用智能手机和普通的一瓶茶，具有几乎均匀的圆柱形部分，其中充满了不同水平的水，模仿了通用的亥姆霍兹共振器。吹过瓶子，会产生不同的声音。利用智能手机强大的处理能力，实时获得声音频谱和共振频率。
英文摘要：
Resonance is an ubiquitous phenomenon present in many systems. In particular, air resonance in cavities was studied by Hermann von Helmholtz in the 1850s. Originally used as acoustic filters, Helmholtz resonators are rigid-wall cavities which reverberate at given fixed frequencies. An adjustable type of resonator is the so-called universal Helmholtz resonator, a device consisting of two sliding cylinders capable of producing sounds over a continuous range of frequencies. Here we propose a simple experiment using a smartphone and normal bottle of tea, with a nearly uniform cylindrical section, which, filled with water at different levels, mimics a universal Helmholtz resonator. Blowing over the bottle, different sounds are produced. Taking advantage of the great processing capacity of smartphones, sound spectra together with frequencies of resonance are obtained in real time.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
