This week we learnt about Water Waves. Some assumptions are made when looking into these waves. We assume that the flow is incompressible and irrotational, and therefore: We also assume that g is the only force implied, and that there is no surface tension. Also, it is an inviscid flow, the velocities are small, the water […]

Let’s start with a quote. “When a fluid is both frictionless and irrotational, pleasant things happen” – F.M White The Potential Flow or velocity potential exists as the velocity field as the gradient of a scalar function. If a flow is irrotational, then its curl will equate to zero, and if a flow is incompressible, […]

Euler’s equations are a set of equations similar to the Navier-Stokes set, but looking at conservation and non conservation results.

This week was consolidation week, and we have to talk about dimensional analysis. As with any equation, we have variables, and in this topic, we use mass, length, time, and temperature. For those of you that would argue for the fifth and sixth variables, electric current and luminosity intensity, they are not applicable in fluid […]

To continue smoothly from last week, we are now looking at the Stream Function. This is a function used to map the streamlines of a fluid, which we’ve previously discussed. This will be a constant, as it is tangential to the velocity vector at each point. For incompressible flows, we use velocity and density. To check […]

We’ll now start to look properly into the world of inviscid flows, and in particulary here, how we map them out. We can map flows by plotting streamlines, and pathlines. Streamlines are points which show the instantaneous direction of the velocity at any given time, and pathlines map out the trajectory of a particle in […]

This week we were talking about Dimensional Analysis. It forms relationships between factors involved in a physical situation. In fluid dynamics, we use Length=L (Metre in SI units) Mass=M(Kilogramme in SI units) Time=T(Second in SI units) Temperature= Θ(Kelvin in SI units) Electric current=A(Amp in SI units) Luminous intensity=I(Candela in SI units) Here is a table […]

The Navier-Stokes equations help determine its motion. There are different equations for a compressible and in compressible fluid and they are as follows. We learnt to derive these using the continuity equation. There are no exercises for this as we will be going back to inviscid flows next week. Currently I think I understand this, […]

So, this week we had a change about. We had a lecture on viscous flow and a taster into our term two syllabus. Viscous flow takes into consideration the viscosity of a fluid. Viscosity essentially being the thickness of the fluid, for example syrup has a higher viscosity than milk. The viscosity of most liquids […]