If we had more time, we would hope to better our design in a few areas. These are some of the following areas.

Optimising airflow

The fan placement for our dryer has not been optimised, we merely chose a placement that made sense based on experience and what worked during experimentation. If we had done a computer simulation, we would be able to ensure that our current fan set up is the optimal one or to find an even better arrangement of our fans.

Expanding Our Dryer’s Capacity and Capabilities

We would also want to expand the capabilities of the rack, accommodating garments of varying lengths, primarily with an adjustable rack of fans to always blow the bottom of the garment and for the period for the fans to be adjusted automatically with the height they are moved to so that we can always obtain resonance when drying the garment. This could be done with some distance sensors and using the formula for a pendulum’s period. Since we would need to increase the rack’s size to allow for longer and larger garments, we would also be able to increase the dryer’s capacity. Thus, we would be able to achieve a product closer to the initial design we had, capable of drying up to six shirts in a single cycle.

Sketch of our Initial Design capable of drying up to 6 shirts in a single drying cycle.

Incorporating Hot Air

Another feature of our initial design was a heating element so we could have hot air circulate around the drying garment safely.

We had initially used a silicone heating element to achieve this. Unfortunately, the heating element did not get hot enough for effectively heat the air from the fan.

Initial Heating Element Setup with Silicone Heating Element (Brown).

We then explored using a nichrome wire coil like hairdryers do.

Hairdryer and Internal Parts (Source).

In hairdryers, the nichrome wire coil gets red hot, heating the air passed through it. The heating element is kept in place by insulating Mica boards, thus the nichrome wire and outer plastic are not in contact with each other.

One of the issues with using a nichrome wire coil in our dryer is being unable to safely suspend the nichrome coil in a way that still allows the aluminium pole to be safe to the touch. Additionally, any 3D print that would be in contact with the hot wire would likely melt due to the melting point of ABS plastic being about 200 °C and the hot wire heating to close to 350 °C.

Findings and Calculations on Feasibility and Power Consumption of Nichrome Wire Coil for Heating.

Moreover, for the hotwire to heat to 350 °C, the wire would need about 100W of power (40V, 2.5A). Thus, we would have to incorporate resistors into our overall circuit since the fans draw 4W of power (12 V, 0.3 A).

Ultimately, the work and further research needed to implement the heating element was too much for the time we had remaining to complete the project.

Lastly, we had hoped to establish an Internet connection for our dryer so that the user could receive a notification on their phone when the drying cycle completed. We had thought it to be a fun addition to our drying rack, one that some tumble dryers already have today.