What is the difference between ventilated discs and disc brakes?
4 Answers
The differences between ventilated discs and disc brakes are: 1. Different application positions: Ventilated disc brakes are primarily applied to all four wheels, while disc brakes mainly function on the rear wheels. 2. Different braking effects: Ventilated discs can quickly dissipate heat during braking, whereas disc brakes may experience reduced braking efficiency due to heat buildup. The working principle of ventilated discs is: The centrifugal force generated while the car is moving enables air convection, achieving heat dissipation. The working principle of disc brakes is: The brake pads on the calipers interact with the brake discs connected to the wheels during braking until the wheels stop rotating.
I've got a lot to say about brake system upgrades! Back when I was driving on mountain roads, I kept smelling this burnt odor, which got me thinking about the difference between vented discs and solid discs. Vented discs have cooling channels sandwiched in the middle, like installing an exhaust fan for the brake pads—heat dissipates quickly during high-speed hard braking. After upgrading my hot hatch to vented discs, I never experienced brake fade again during consecutive cornering. Solid discs, on the other hand, are like chunks of iron—cheap and durable, but when you're stuck in summer traffic and brake until smoke comes out, it feels like stepping on cotton. They tend to warp and vibrate after about 150,000 km. Many economy cars use solid discs on the rear axle to save costs while pairing vented discs up front for safety. Now you see why tuning shops always recommend vented discs!
After a decade in the auto repair shop, customers always ask which brake rotors are the most practical. Solid rotors are just thick iron discs—simple in structure and less prone to cracking, commonly found on the rear wheels of economy cars. Vented rotors, on the other hand, feature a clever dual-layer design with radial fins sandwiched in between, using centrifugal force to fling hot air out from the center. Last time I replaced the front vented rotors for a Civic owner, he poked at the cooling channels with his finger and marveled at the ingenuity. For daily commuting, there’s not much difference between the two, but if you frequently drive on highways or tackle steep descents with a full load, vented rotors can lower brake temperatures by over 100 degrees, even preventing brake fluid from boiling. Remember, don’t cut corners by using solid rotors in place of vented ones—not only won’t they fit, but the wheel rim might also scrape against the caliper.
Physics teacher explains it more intuitively: Friction generates heat due to the law of energy conservation. Solid discs are like solid iron blocks—heat gets trapped inside when heated, allowing temperatures to soar to 700-800 degrees. Ventilated discs are designed with the principle of thermal convection in mind. When rotating, cold air is drawn in from the center of the hub and spirals through air channels to expel heat from the edges of the disc. Experiments show that after ten hard brakings under the same conditions, the surface temperature of ventilated discs is about 40% lower than that of solid discs. This is why, during aggressive driving, ventilated discs experience heat fade three minutes later than solid discs. However, solid discs are perfectly fine for grocery-getters, as their heat capacity is designed to match the intensity of everyday driving.
