Aerial Wheels - Over Aerostability and Sail Effect
Monday, October 22, 2018 9:51:57 AM America/New_York
The selection of aerodynamic wheels is great. There are many manufacturers offering wheels in different rim heights, designs, quality levels and price categories. It's hard to keep track. What is important in the choice of wheels and how much does an aerobar actually deliver?
When you talk about being as "aerodynamic" on the bike as possible, that means keeping air resistance as low as possible. If we look at the overall system, consisting of athlete and bike, then the complete wheel is responsible for only 25 percent of the total air resistance . The wheels - as part of the complete wheel - account for eight percent of the total drag. Whereas the athlete a whopping 75 percent of power. The legitimate question is, why on earth should one spend so much money on wheels with this knowledge?
Imke Oelerich deals with this topic and mentions her three reasons why she still thinks it's worth investing in high-quality wheelsets.
Aerial wheels and aerostability
Stability means having the bike under control regardless of the wind situation. If you can not control your bike, you'll have to leave the aeroposition, reach for the basebar, and the aerodynamic drag you create as an athlete (75 percent) will "slow you down." If you can hold your position, exactly these 75 percent of air resistance will be positively affected. Did you know that wheels really do make a big contribution to the improved handling of your bike? If the aerofoils of your impeller meet the highest quality standards, then these are ideally designed so that the so-called steering torque remains low even at high angles of attack and the stall is very smooth and even. These very characteristics are crucial
Aerial wheels and sail effect
Another advantage of good Aerofelgen is the so-called sail effect. Whether you believe it or not, wheels can produce noticeable forward thrust (negative air resistance) through a higher angle of attack. The angle of attack is the angle of Windanströmung and direction of the athlete. Higher approach angles of more than ten degrees are quite common in reality. The lower the profile height of the rim, the greater this sailing effect can be. On the rear wheel, you can almost always drive a very low rim height, since the air is already very swirling, until it hits the rear wheel and thus has little negative impact on the stability. In strong and gusty wind conditions, you should make sure to reduce the rim height of the front wheel accordingly. The front wheel is flown directly and is accordingly wind-prone. Say it affects the steering behavior significantly more than the rear wheel.
An aero wheel is more than an aerofoil
The Aerofelge is just the beginning. If you want to take money in order to get an aerobatic bike, then it is a "good thing". Make sure that not only the rim but also the spokes, the nipples and the hub shell are aerodynamically optimized. Aero-optimized spokes - flat forged - have a huge impact on the rotational air resistance. This is the air resistance to which the spokes are exposed as they rotate about the axis of the impeller. With the nipples you should make sure that they are within the rim. The hub shell also has a measurable positive influence on the air resistance by reducing the flange height and the hub diameter.
However, with all the points you should always keep in mind:
Aerostability goes before sail effect!
If you're small and light, you'll want to reach lower rim heights in strong winds to ensure aerostability. If you can hold your aeroposition, you will benefit more and more from it as the sail effect.
Now you should be provided with enough information to equip yourself with the right wheelset, even on a stiff North Sea breeze or cross-winds in Hawaii, to fully exploit your performance.