Heat Shielding

[CorbinJ PBR]

I was just wondering what some other teams use for heat shielding. Specifically heat shielding that can be attached to the back of the drivers seat to protect them from the heat from the header, or something that can be used to coat the inside of the engine bay of a carbon fiber monocoque.

[NickFavazzo]

We have used ceramic coatings on the exhaust (does a great job alone) then some aly sheet and insulation (wool type stuff, glass, ceramic fibre etc) gold leaf if you have the sponsorship, I have also heard of a company doing metallic/ceramic/gold carbon coatings in the uk so that may be something to look into. When we design the exhaust we do try to provide as much gap as possible to components and with plenty of heat shielding and making sure the hot air can escape the carbon can stay well below problematic tempertures

[CorbinJ PBR]

We Do the ceramic coating on the header with fiber glass wrap as well. Unfortunately it still gets quite hot. We then put a low quality reflective backed heat shielding on the back of the seat but once again it still gets quite hot, and the heat shielding eventually gets burned to crap. There's gotta be some higher quality stuff out there that we can use for the back of the seat.

[Menisk]

We had our fuel tank literally mm away from the headers this year and had it wrapped in rockwool and then we covered that in reflective tape. So maybe the same could work on the back of your seat. Adhere some rockwool to the back of the seat and then use reflective heat tape over the back of that.

[Nath_01]

Corbin,
We used a similar stuff to this in Formula ford to protect the fiberglass bodywork from the exhausts which virtually sat directly on top.

http://www.revolutionracegear....1&PSV=Primary&CDO=12 (http://www.revolutionracegear.com.au/index.php?PCID=10314&PSO=245&PSID=3389010401&PSV=Primary&CDO=12)

It's not 'cheap' but when is anything cheap in motorsport ehh???

[Warpspeed]

A reflective heat shield, maybe thin gauge mirror finish stainless should bounce that infrared right back.

But you also need an effective air space between heat shield and seat to circulate cool air between.

You may be able to adapt the engine cooling fan to somehow draw, or blow, some cool air behind the seat.

Insulation probably will not work well enough just by itself, it really needs some active heat removal.

[Boffin]

Having worked at an OEM supplier for heat shields during my time in formula, I'll share what I know.

The two things you need for effective heat shielding, is a barrier to reflect the radiant heat and an air gap to insulate (both before and after the heat shield).

The stuff that nath posted is nothing but shit and glitter. Admittedly we used to sell it, but for the only reason that people asked for it (same with header wrap actually). Miss information spreads quickly (they run it on car X, so it must be good)

The best heat shields are multiple layers (generally aluminium or steel), with either an air gap between the layers or an insulating material.
Plain sheets of material do not work either. They need to be dimpled or corrugated to provide an irregular surface so heat is not reflected straight back and to increase the surface area of the material.

The best way to stop the heat is at the source. I’ll use my example of a car and exhaust pipe heat getting into the cabin here.
The best option to stop heat getting into the cabin is to install a shield onto the exhaust pipe, sitting about 10mm off the pipe. By mounting the shield with a gap to the pipe you still allow the exhaust pipe to grow and swell as it heats up and does not trap the heat in the pipe, hence it will not damage it over time. Mounting the shield to the pipe allows the shield to heat up slightly but to not heat the floor pan of the car. The further benefit is by allowing an air gap between the pipe and heat shield, and an air gap from the heat shield to the body; you have two sides of the heat shield for airflow to draw the heat out of the shield.

The medium option is to mount a heat shield on the floor pan of the body. This stops the radiant heat getting directly to the body, and by making the heat shield out of aluminium in this case, allows it to heat up quicker than what the steel body would. This creates a heat sink of greater area than the exhaust pipe for which the air flow can draw heat from.

The worst option is the put a shield inside the car. However by this time the heat is already in the cabin and you are more trying to create a large heat sink that won’t heat up enough in normal driving.

Now, what I did on our car after learning some of this was to run a 6 layer heat shield that we made as the OEM manufacturer. All aluminium with each layer dimpled in a differing pattern, which captured air in between the layers.
The exhaust was really close to the chassis bars.

http://sphotos-b.ak.fbcdn.net/hphotos-ak-snc6/227947_10100164375467132_4133184_n.jpg

We ran gold reflective tape on the tank (carry over from previous years), and I made up a 3 sided box of the heat shield (exhaust to oil cooler, exhaust to tank, exhaust to firewall). This was in two pieces, oil cooler and fuel tank as one.
The shielding to the driver was on the exhaust side of those chassis bars, and the aluminium firewall was on the inside of the chassis bars.
We used to run a peak Exhaust gas temperature of 750°C to 800°C. I never saw much increase in fuel temp from data logging (10°C increase over the length of an extended enduro, after the car had been running for most the day. Fuel lines were unshielded though), and I could never feel any temperature in the firewall with my hand after running.
You can see the firewall shield here.

http://sphotos-e.ak.fbcdn.net/hphotos-ak-ash4/317180_10100323543153812_697048169_n.jpg

This is a good range available in North America
http://vibrantperformance.com/...cPath=1022_1355_1356 (http://vibrantperformance.com/catalog/index.php?cPath=1022_1355_1356)

Any questions feel free to ask and I’ll help where I can.