Termofluido

During the semester of Thermofluids was studied in the classroom, how was calculated the losses in a pipe for the determination of such friction factor. In order to understand how this process worked in practice, an experiment was conducted in a laboratory of the University of Derby. Using a pipe in which water was poured into their beginning and if a route guide at its end which was poured into a tank (Venturi tank). During this course was observed and measured the pressure at various points with different flow rates, so that it was possible to build charts and determine their losses.

The aim

The purpose of this experiment is to determine the empirical loss in energy (or head) from fluid flow in a converging - diverging tube for various flow rates.

Experiment, Apparatus and Data collected

The process was performed three times: the first flow slowly, the second a bit faster (average flow) and third with a fast flow. Water was added to the tank as previously defined, timing the time to achieve this. It is known that the full tank has 10 liters of water and then we read the height of the columns of water (pressure heads). The pipe diameters were also recorded (already measured and were supplied). The photos illustrating the experiment and the data collected can be viewed below.

Calculation methodology

It is necessary to know which way it is possible to relate the data collected to find the speed. For this it is imperative to find the mass of water that was in the tank as full as we know that the volume was 10 liters and assuming that the density of water is 1000.00 kg / m³. With this data in hand the mass flow rate can be calculated:

Q= m/t [kg/s] (1)

It is known that the mass flow rate can also be calculated as follows:
Q= A U [kg/s] (2)

The density can be calculated:

ρ= m/v [kg/m^3 ] (3)

Substituting (2) into (1) we have the mass flow:

Q= ρv/t [kg/s] (4)

And now