F1 racing... little openings

[Chris Ostlind]

Hey, guys... take a good look at the photo shown below. Yeah, go ahead and blow it up. (I know you're going to anyway)
http://www.boatdesign.net/gallery/sh...hp/photo/16991

Shown is the F1 Powerboat hydroplane of Sami Selio flanked by two lovely ladies in sponsor, Red Devilish outfits. Now look down between their spread legs... on the underside of the boat's bows. Do you see those aligned openings?

I'm not much into F1 racing other than it's fun to watch. I'm not especially connected to the design aspects of the boats and I'm very curious as to the purpose of the, a-hem!... openings that are shown. Are they for air entrainment that facilitates a faster, more efficient planing function at the hull step, or what?

Anybody out there with a take on the design application?

[tunnels]

Originally Posted by Chris Ostlind

Hey, guys... take a good look at the photo shown below. Yeah, go ahead and blow it up. (I know you're going to anyway)
http://www.boatdesign.net/gallery/sh...hp/photo/16991

Shown is the F1 Powerboat hydroplane of Sami Selio flanked by two lovely ladies in sponsor, Red Devilish outfits. Now look down between their spread legs... on the underside of the boat's bows. Do you see those aligned openings?

I'm not much into F1 racing other than it's fun to watch. I'm not especially connected to the design aspects of the boats and I'm very curious as to the purpose of the, a-hem!... openings that are shown. Are they for air entrainment that facilitates a faster, more efficient planing function at the hull step, or what?Anybody out there with a take on the design application?

Yip !! when a tunnel goes into a corner they drop there nose and the back lifts then round they go ! its nose up and tail down and away all in the blink of an eye .
Its when the nose drops that they are getting the water slightly airated with bubbles along the surface and will have a little less water friction !!
Clever aaahhhh!!!

[tom28571]

Rather strange. If they are for air inlets, it would seem not to be the best place or shape for it. I've no clue.

[tunnels]

Originally Posted by tom28571

Rather strange. If they are for air inlets, it would seem not to be the best place or shape for it. I've no clue.

You need to watch very carefully some F1 tunnels boats in action and you will see what i was saying about cornering . Its only airating the front portion of the hull !!! the rest of the time the boat is airbourne and flying !!

[terhohalme]

I think, they are for aerating the first step of the bottom and to prevent huge slowering due suction in tight corners.

Well, tunnels, you were faster...

[tunnels]

Originally Posted by terhohalme

I think, they are for aerating the first step of the bottom and to prevent huge slowering due suction in tight corners.

Well, tunnels, you were faster...

A boat designer friend and my self used to design and build tunnel boats ,we also designed a few of the 45 sst class .
At 80mph they will turn without slowing down at all just drop the trim and turn an up again . The G force is quite high on the driver and one side of the cockpit was completely padded for him to lean into !!
Tunnels boats are the tip of powerboat design ! its where boats become airbourne and fly and you have 3 amazing things all happening one after the other , hydrodynamics , aerodynamics and surface effect , all 3 need to be understood to make tunnels work !

[baeckmo]

Originally Posted by terhohalme

I think, they are for aerating the first step of the bottom and to prevent huge slowering due suction in tight corners.

That's what they are doing. The front step is preventing a deep dive of the narrow hull when trimming down (or coming nose down after beeing airborn). Since that part of the bottom is convex, without those flat pads (ending in a step), the flow would create a downward suction, that could result in the nose digging in and a very spectacular rollover.

"Covering the bottom aft of the step with bubbles" is nonsense; in the hydrodynamical sense, that air is venting the step and thus preventing a low pressure zone to develop, nothing else!

.....Provided we all talk about the same openings, that is..........

[tunnels]

Originally Posted by baeckmo

That's what they are doing. The front step is preventing a deep dive of the narrow hull when trimming down (or coming nose down after beeing airborn). Since that part of the bottom is convex, without those flat pads (ending in a step), the flow would create a downward suction, that could result in the nose digging in and a very spectacular rollover.

"Covering the bottom aft of the step with bubbles" is nonsense; in the hydrodynamical sense, that air is venting the step and thus preventing a low pressure zone to develop, nothing else!

.....Provided we all talk about the same openings, that is..........

Tell me about the sort of hydrodynamics you are into ??

[baeckmo]

Multiphase flows, including cavitating and free gas effects, primarily applied to rotodynamic machinery, but also in the design of planing hulls (including catamarans) etc. Also involved in post-graduate lecturing for engineers in the field since early seventies. Last 25 years as consultant, often involved as a non-affiliated third part in breakdown investigations.

And you sir??

[Dan Ellison]

Originally Posted by Chris Ostlind

Hey, guys... take a good look at the photo shown below. Yeah, go ahead and blow it up. (I know you're going to anyway)
http://www.boatdesign.net/gallery/sh...hp/photo/16991

Shown is the F1 Powerboat hydroplane of Sami Selio flanked by two lovely ladies in sponsor, Red Devilish outfits. Now look down between their spread legs... on the underside of the boat's bows. Do you see those aligned openings?

I'm not much into F1 racing other than it's fun to watch. I'm not especially connected to the design aspects of the boats and I'm very curious as to the purpose of the, a-hem!... openings that are shown. Are they for air entrainment that facilitates a faster, more efficient planing function at the hull step, or what?

Anybody out there with a take on the design application?

Sorry, but they are not openings, what you see are the washers and bolts holding the collapsable sponson tips, a safety feature.

[Chris Ostlind]

Wow! Now that's a different take worth exploring. Thanks, Dan.

Maybe we were all so distracted by the Lil' Devils, that we failed to read the foreshortening effect of the photo angle?

[TollyWally]

Had me fooled

[tunnels]

Originally Posted by Dan Ellison

Sorry, but they are not openings, what you see are the washers and bolts holding the collapsable sponson tips, a safety feature.

are you looking at the same picture as everyone else ? are we even on the same planet ?

[Dan Ellison]

Originally Posted by tunnels

are you looking at the same picture as everyone else ? are we even on the same planet ?

Yes same picture. If your talking about those little black things that may look like a slot are actually a black anodized washer. If you look on the top and the nose of the capsule, they are there also.

[terhohalme]

But our explanations were great...