Aim
The aim of this experiment is to determine the loss coefficient (K) for a number of bends and fittings, then to compare these results with results obtained from other more accurate sources such as textbooks. According to the results from textbooks the calculated disturbances in flow proves that velocity and pressure is lost through heat and friction.

Experimental * The water inlet * Water collection basin * Rubber ball * Hydraulic bench * Stopwatch
Procedure
Before the experiment is conducted the pump is turned on to bleed the air from the lines. Once this is done the flowrate it gradually increased by the individual to the highest possible value, without the menisci going to a point where it cannot be read.
The next task is to identify the key components of the systems and the direction of water flow. An initial reading of the manometers is then taken from both the H1 and the H2. Once this is done 5 more readings are to be obtained with varying flowrates, this is done by adjusting the flow control valve.

Results and discussion
The full results and raw data gained from the experiment is shown in Appendix A.
Examples of the calculations are given in Appendix B.

The loss coefficient vs head loss graph above represents the gradual loss in velocity over the length of the piping. Due to factors such as friction and heat energy is lost from the fluid. It is also clear that the diameter variations shown in the enlargement and the contraction create major fluctuations in velocity. This is shown by the enlargement having a consistently low loss coefficient and the contraction having a consistently high loss coefficient. This is not apparent in the other areas as their diameter is the same the velocity falls at an average rate.

| Average | Results | Obtained | | | Mitre | Elbow | Short bend | Long bend | Enlargement | Contraction | 0.774788 | 0.757011 | 0.33487775 | 0.3567411 | 0.967083827 | 0.22037127 |
Table 1- average loss coefficients | Published | Results | Obtained | | | Mitre | Elbow | Short bend | Long bend | Enlargement | Contraction | 1.1 | 1.5 | 0.64 | 0.72 | 0.2 | 0.25 |
Table 2- Published loss coefficients
The final results obtained show similarities to the published results with only minor variations. The variations would most like be due to simple errors either with calculations or during the experiment itself. From my results I see that most of my pressure and velocity was lost in the enlargement of the pipe, most likely due to the variation in diameter allowing the fluid to go through slower.
Conclusion and recommendation
During this experiment a vast knowledge was gained about the relationship between flow rates and loss coefficients. It shows how minor difference in the piping can have major effects on the fluid itself. Although my results were not the same as the published results they did show the relationships quite clearly. The results clearly showed that the increase in diameter dramatically reduced the velocity and that the decrease in diameter dramatically increased the velocity, which was to be assumed. Therefore to gain a faster velocity simply use a thinner pipe and vice versa.

References
M.Potter, D.Wiggert (2009). Mechanics of fluids. Cengage learning, USA, pg 314-316.
S. Manning (2011), Fluid mechanics laboratory manual 2011.