## Summer Internship 2013

Before I write down about my current stuff, I think it would be better to introduce the geeky stuff I have done last summer. It was an internship, so there was nothing extraordinary about it. Having an interest in fluid dynamics, in the CFD lab of National Tsing Hua University, I learnt about lattice Boltzmann method and GPU programming (CUDA as they call it). Throughout a time span of two months, there were two basic fluid flow problems that I simulated.

1. Poiseuille flow (Flow in a channel): This is quite a classic problem. For a layman, it could be simply called as a pipe flow (though technically both are different things). If anyone has a little idea about fluid dynamics, fluid near a boundary has the tendency to acquire the same velocity as that of boundary (that we call as no-slip condition). It is because that the fluid molecules near the boundary stick to the surface while the molecules far away are not influenced by this boundary directly. But, since a fluid has viscosity (a property which defines it’s resistance towards shearing), there is some influence on the molecules far from the boundary. THAT IS WHAT CAN BE OBSERVED! Fluid near the boundary has the zero(or almost zero) velocities while fluid between the two boundaries have the maximum (indicated by red color). This is a simple flow, not much complications are involved in it. Velocity profile at any cross section is parabolic (which is very simple).

2. Flow over a cylinder (Von Karman vortex): This was the second and last problem which I simulated last year. It was a tough one, atleast at that time. It is about the flow pattern when a cylinder is inserted in to the same channel. Surprisingly, it is one of the complicated yet extremely beautiful flow. I am not gonna go much in to “how it is solved”. This is also one of the widely researched flow pattern as this forms the basis for calculation of lift and drag forces on other structures such as airplane wings, buildings etc.

So, this was, in a short about my past research at NTHU. Now, I am here, with a little more knowledge and a bit more passion to learn more, and do more! Good luck to me.