I Is the Blade Loading Sufficient for Minimum Sliding Resistance at Top Speed?

[Colin Wilson]

I'm building a model as shown below (side, front, back). In order to measure its air resistance I will be mounting it on temporary ice blades (Green) and driving it down a long skating rink. The model has a pressure sensor incorporated into the motor / propeller assembly and a GPS unit to measure velocity, a microcontroller collects the data (pressure / velocity) and writes it to an SD card. As it sits the blade loading would be as follows:

• (3) SS blades = 30cm long * 1mm thick
• Top speed 90kph (82fps)
• Loading 2kg per blade = 0.67kg / cm2

My question: Is the blade loading high enough given the top speed to ensure minimum sliding resistance? I can add more weight to the model or I can reduce the blade lengths.

 

[jrmichler]

I searched ice skate friction, and found myself traveling down a rabbit hole of interesting information. But I did not find an answer to your question. You apparently already understand that pressure between the skate blades and the ice is a key variable, as is also the ice temperature.

I suggest that you treat the blade loading as an experimental variable, and run a series of experiments to optimize it.

 

[Colin Wilson]

Thank you for your input.
In any case woke up this morning and decided to put pressure sensors on each blade and subtract those readings from the motor reading so problem solved!