It‘s not so much about that it’s induction, it’s what kind of cooking you do. Greasy smoky things like bacon will be that way whether cooked on induction or not.

Here is a thread from a couple weeks ago: [https://www.houzz.com/discussions/cfms-for-induction-range-dsvw-vd~5597927?n=23[(https://www.houzz.com/discussions/cfms-for-induction-range-dsvw-vd~5597927?n=23)

“what is the recommended distance from the cooktop to the ceiling ventilation?”

The distance from the cooktop to the bottom of the hood must be between 30“ and 36”.

The reason the OP can't find CFM requirements anywhere (except for 100's of threads here at the Garden Web/Houzz appliance forum) is that in the residential cooking appliance world, magic and folklore were deemed an adequate substitute for science and engineering. In the commercial world, there is an expansive collection of measurements that can be generalized not only to commercial ventilation, but also to residential ventilation.

tl;dr

Use 90 CFM per square foot of hood entry aperture to assure that the portion of the cooking plume captured by the hood entry aperture is contained by being pulled through the baffles instead of reflecting off of them and escaping. This specific flow rate has to be achieved in the present of pressure losses from the hood entry aperture to outside and back to the cooking zone. This requires a higher rated blower; without exact analysis, a factor of 1.5 should prove sufficient.

Hoods are manufactured with a recommended distance above the cooktop. A rationale for height vs. hood entry aperture size can be made based on measurements of cooking plumes upward expansion. At 30 to 36 inches, overlap of 3 inches all around may be sufficient. This means that an 18 x 36 inch cooktop should have a 24 x 42 inch hood. This should be the entry aperture for best results, so with switches and lights a somewhat greater front to back depth may be desirable along with installing the hood so that the center of the hood entry aperture (and not the hood overall area) is at the center of the locus of pan base extents over the cooking zones.