Size of orifice

 

The orifices were made by inserting a needle and puncturing the plastic container, slowly increasing the orifice size with each attempt. The orifices were then estimated according to the size of the needle used for creating the orifice.

 

During the first attempt we wanted to observe the phenomenon and see what happens when this parameter is changed. For example in the following graph we changed the diameter of the orifice.

 

Graph 1: Rough height-diameter dependency.

 

During the first try, we got some very inconclusive results, alas a pattern was showing. There were not any backup experiments and we had no error estimates, but noticed that as the size of the orifice increased the phenomenon was less visible and effective. To better the following results, it was agreed upon to measure the size of the orifice/container with their radii rather than their diameter.

 

To understand the impact of the size of the orifice, we had an experiment with 9 identical containers and repeated the experiment twice for each container to get 18 attempts for each orifice. The containers were not cylindrical, rather they were inclined, resembling a cone, without its tip. We used water as the liquid of choice, and changed no other factors, other than the radii of the orifices.

 

One set of the collected data is represented here, as an example of how it varies on its own:

 

 

Graph 2: Attempt number measurements.

 

 

From this we noticed that whilst the same device was used to make the orifices, there is some variance in the results. Although it is not very drastic, further investigation is required. This is likely caused by human inaccuracy-which unfortunately cannot be avoided, but it can be measured and used accordingly.

Once we plotted the data we saw a clear-cut dependence.

 

The following graphs show that:

 

Graph 3: The error bars on this graph represent the standard deviations of the data.

 

This is highly compliant with the theoretical model, as we expected that there would be a reciprocal dependency of the radii on the height. And there clearly is!