Kool Babys First Prototype¶
For the initial testing phase I have 2 main goals:
Firstly for the freezer unit, what is the best combination of metallic straws and cooling gel. My hypothesis is that more straws will increase the units cooling ability but reduce its cooling longevity through both speeding up the energy transfer process and while also reducing the volume of cooling gel in the unit (due to limited space). I will also test straws of different diameters to test for the above.
Metallic straw selection will also be based on Cost / Availability, Safety and both Thermal Expansion (I don’t want the unit cracking in the freezer) & Conductivity properties.
Secondly, I would also like to experiment with the fan output, can I design a variable fan output that best achieves its cooling ability.
DOES IT EVEN WORK!!!
I would like to also understand if this product idea is practical, there’s no point continuing with the design if testing shows that I would need a freezer unit with 10kg of cooling gel for 5 mins of use!
First Design¶
The goal of my first design was just to prove that my idea could possibly work, so no real thought went into aesthetics or the head fan unit (apart from being able to attach a fan). I wanted to find out if my core concept, a heat exchange type body could possibly work, that after testing it was worth fine turning my idea.
The above picture shows my initial design as I prepare to print. On the left is the very crude head / fan unit, with the main body being split into two pieces (center & right). The main body was split in two pieces due to height restrictions on the Ultimaker printer, and also for ease of assembly when inserting metallic straws.
A quick note, the metallic straws being used have a diameter of 6mm. Because I’m filling the main body with freezer gel, I wanted a tight fit when inserting the straws into the body to prevent leakage, but not too tight preventing assembly. So I did the quick print shown above, testing diameters of 5.8mm, 5.9mm, 6.0mm & 6.1mm. When trying out the straw fit on this test print, I decided 6.0mm diameter was the best fit and used this sizing in my design.
