Week 6

For this week, I'm doing research about the pipe. When talking about pipe, there were a lot of thing that need to be considered such as the type of pipe. A lot kind of pipe that had been made such as PEX Pipe, PVC pipe, Rigid Copper Pipe, ABS Pipe, Flexible Copper Pipe, Galvanized Steel Pipe and Case Iron Pipe. A lot of pros and cons in this kind of pipe. As for my project, I'm using PVC pipe.

Type of Pipe

PVC stands for polyvinyl chloride. Of the different types of plastic pipe used for water supply, PVC has a wide variety of plumbing uses, from drainage pipe to water mains because it has lighter and easier to work with than traditional galvanized steel pipe. PVC pipe is moderately easy to install and requires little more than hacksaw and mitre box to cut. PVC glues together with solvent. Below listed the pros and cons of PVC pipe.

Pros

• Diameters clearly marked on the white surface of the pipe.
• Inexpensive and can be used for long runs such as for irrigation.
• Flexible

Cons

• Pipe cannot be unjoined and must be cut
• Glued pipes can be prone to be leaking
• Fragile and tends to shatter. 

We also can use galvanized type of steel/iron pipe but it got greater problem where the flow of water become slow or static for periods of time due to rust discoloration caused by internal corrosion. This type of pipe only used in older homes. This will nit used for water supply in new construction or remodel projects. 

Type of pipe

Pressure

We also need to take note about the flow of water in the water pipe. It's because of the present of friction on the wall of the pipe. In fluid flow, friction loss (or skin fraction) is the loss of pressure or "head" that occurs in pipe or duct flow due to the effect of the fluid's viscosity near the surface of the pipe or duct. When the friction is high, the flow of water become slow thus affect the rotation of turbine. For PVC pipe, the friction on the wall is lower than galvanized steel pipe. We can calculated the friction loss between the pipe surface and the fluid flow at the physical properties of the system. These condition can be encapsulated into dimensionless number Re, known as the Reynolds number

where V is the mean fluid velocity and D, the diameter of the (cylindrical) pipe. In this expression, the properties of the fluid itself are reduced to the kinematic viscosity , v

where u = viscosity of the fluid (SI kg/m/s)