CONCLUSION The testing stage wasn’t as successful as we had hoped as we only managed to ascertain one true position of the floats and a volume of water added at which the model was stable. After the seal broke around the bottom, we couldn’t test further. However, the results that we did obtain have led us to the following conclusions in relation to our specification. Assessment of Buoyancy
The model itself is very buoyant. It floats much higher in the water than was initially expected. This has helped as we have not needed to add any means of flotation. Instead, we have had to stabilise it. However, left to its own devices, its buoyancy is ambiguous as it isn’t buoyant once it has fallen over and began to sink. If anything, the buoyancy has also caused problems as we have had to add mass, in the form of water, to help in sit lower in the water to make it more stable. The real tower will therefore fall victim to the same flaws in the design. It will sit high in the water with a strong chance of toppling over. Assessment of Capability to be Towed
Towing the unit will require incredible skill. The pontoons that we have added have helped somewhat in stabilising the unit but have not been totally effective. The pontoons added, were streamlined and so would create little drag compared to some of our previous ideas for stability. The pontoons are also very easy to steer. They would naturally follow the tow rope and so could be manoeuvred easily. We had 2 tow ropes initially but then decided to have 4, 2 on each pontoon. One of these was positioned above the water’s surface, and the other was below. This helped to stabilise the two moments created and caused equilibrium at the towing force. This made the towing process much easier. However, the pontoons didn’t prevent forward and back swaying motion and so we believe that for the real construction, the pontoons will have to be at least 25% longer. They already seem to stop sideways swaying but when the ropes are pulled with anything other than a small force, the model topples forward in the direction it is being pulled. Also for the full size base, towing would need to be completed by at least two vessels as the construction would need to be pushed and pulled into place at the site that it will be sunk. If only one boat is used, then there would be no control over pushing the model away from the boat. Assessment of Resistance to Inclement Weather
This was hard to accurately replicate for our model. For example, in a scale model situation, a small wind to humans is almost gale force winds to the model. The small natural ripples in the water were relatively large waves. We did however, use a rugby ball to simulate larger waves and to some degree, the model did remain stable. The stability would be improved considerably once the pontoons have been made larger. We would advise however, that when the real base is launched, it should not be done in bad weather conditions as this would add to the unstable nature of the tower. The pontoons are essential in minimising the risk but if the risk factor is raised, even more strain is placed on the tower. Engineering Education Scheme: The Report | Conclusion
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