Acoustic Materials and Metamaterials

COURSE OUTLINE: The study of electromagnetic and acoustic waves is an endeavor that dates back centuries. An important sub-domain of this field that effects our daily life is the use of acoustic principles to control environmental noise. In this regard, acoustic materials, which are materials designed to manipulate sound wave propagation, are of prime importance. Within this field, about three decades ago, the concept of metamaterials was proposed that has created a revolution. Theoretical formulation and experiments have shown the feasibility of realizing man-made acoustic metamaterials that can manipulate waves beyond the defined limits of those found in nature. Therefore, within a time span of 15 years, acoustic materials have emerged as an active field driven by scientific discoveries and diverse application potentials in machinery noise control, frequency filtering, speech transmission technology, acoustic imaging, and cloaking. This is the first-ever organized coursework on acoustic materials with a special focus on acoustic metamaterials. This course will cover the following topics:

• Acoustic fundamentals
• Theory and design principles of acoustic barrier materials, sound absorbing materials
• Limitations of conventional materials
• Principles of acoustic metamaterials
• Theory and design principles of membrane type metamaterials, of sonic crystals
• Guidelines for selecting acoustic materials

Acoustic Materials and Metamaterials.
Lecture 1: Introduction.
Lecture 2: Sound Wave Propagation in Fluid-I.
Lecture 3: Sound Wave Propagation in Fluid-II.
Lecture 4: Sound Wave Propagation in Fluid-III.
Lecture 5: Sound Propagation at Medium Boundaries-I.
Lecture 6: Sound Propagation at Medium Boundaries-II.
Lecture 7: Standing Waves and Modes.
Lecture 8: Sound Signal Analysis-I.
Lecture 9: Sound Signal Analysis-II.
Lecture 10: Principles of Noise Control.
Lecture 11: Acoustic Materials.
Lecture 12: Enclosures.
Lecture 13: Barriers.
Lecture 14: Enclosures and Barriers-Tutorial.
Lecture 15: Sound Absorbing Materials.
Lecture 16: Porous-Fibrous Sound Absorbers.
Lecture 17: Panel Sound Absorbers.
Lecture 18: Helmholtz Resonators.
Lecture 19: Tutorial on Sound Absorbers.
Lecture 20: Perforated Panel Absorbers.
Lecture 21: Microperforated Panel Absorbers-1.
Lecture 22: Microperforated Panel Absorbers-2.
Lecture 23: Microperforated Panel Absorbers-3.
Lecture 24: Introduction to Acoustic Metamaterials-1.
Lecture 25: Introduction to Acoustic Metamaterials-2.
Lecture 26: History of Acoustic Metamaterials.
Lecture 27: Applications of Acoustic Metamaterials.
Lecture 28: Membrane Type Acoustic Metamaterials-1.
Lecture 29: Membrane Type Acoustic Metamaterials-2.
Lecture 30: Membrane Type Acoustic Metamaterials-3.
Lecture 31: Membrane Type Acoustic Metamaterials-4.
Lecture 32: Advantages and Applications of Membrane Type AMM.
Lecture 33: Tutorial on Membrane Type AMM.
Lecture 34: Introduction to Sonic Crystals.
Lecture 35: Fundamentals of Crystals.
Lecture 36: Principle of Working of Sonic Crystals-1.
Lecture 37: Principle of Working of Sonic Crystals-2.
Lecture 38: Tutorial on Sonic Crystals.
Lecture 39: More on Sonic Crystals and Conclusions.