Therefore, modeling of turbulence in such scales is universal and independent of the flow type. Large Eddy Simulation (LES) is an efficient technique based on the elimination of all scales of a flow smaller than a characteristic length ∆, considering that the flow pattern in small scales is homogeneous and isotropic. The accurate simulation of these complex flows is still a great challenge in science.
The occurrence of turbulent flows is quite common in nature and several industrial applications. Future applicability of the model includes observing flow at the exit of both square and round organ pipes in addition to modeling the reed-mouthpiece system of the clarinet. The method described here is meant as a first step to a code that is highly flexible and can be used to study many as- pects of acoustics in musical instruments.
This thesis offers the mathematical and computational background as well as a description of the implementation of the basic LBM for simulat- ing flow in musical instruments. Thus far, the air flow in organ pipes for a two dimensional model was simulated showing oscillating flow by the labium as expected. The accuracy and stability of the model are shown by comparison to various published benchmark tests.
Start- ing as a two-dimensional code in Matlab running on the CPU, the model went through a series of iterations before becoming a three-dimension code in Fortran that was accelerated through the use of GPU parallel computing. Through the use of the lattice Boltzmann method, a series of computational models were created to simulate air flow in woodwind instruments.