I modeled a fan (link 1 has the image) and used a drone brushless motor (KV720) for this model. My goal is to reach 2500 rpm, but the dc motor drew 10+ amps at 12 volts and 1000 rpm. When I pushed a little harder without noticing it, the smell came and I stopped testing. I wonder whatever I do, will I draw 20 or 30 amps at 2500 rpm or can I get rid of this problem if I change the dc motor? (My limit goal is 12 -13 amper at 12v) If yes, How should the characteristics of the dc motor you recommend?
I looked through a car fan manufacturer's catalog. As the fan sizes increased, they used high-torque and large-sized fans. Can I overcome this problem with using a big fan with high torque dc motor? Or whatever I do will I draw extremely high current? In addition, I want to give an example which is lived. I purchased a car air conditioner fan (mini radial fan pic link2) model from this company and I modeled with the same size propeller and tested it with a brushless motor (drone motor). They drew almost the same currents at the same speed, but the dutycycle of the brushless motor was less than 50% (that is, it was actually quite efficient). So if I use a large dc motor for large fan, can I get more efficiency from a brushless motor(drone motor?
Fan 1 : Link 1: The propeller has an end-to-end length of 265mm, a height of 50mm and 10 propellers.
Fan 2: Link 2: The dimensions specified with the product I purchased are exactly the same. The only difference is a dc motor.
Brushless motor link: https://www.f1depo.com/urun/sunnysky-x3108s-kv720-fircasiz-motor