Plasma Jet Ignition

[steve ravet]

Robert Harris wrote:
> 
> Two Parts to the Plasma Jet Ignition.

I'm fascinated by this plasma jet ignition idea.  But, I'm not sure what
the difference is between what is described below and a typical CD
ignition, except perhaps the energies involved, and the pre-chamber.  Is
that pretty much "it"?

--steve

> 
> First part is that the spark is developed in a small - according to patents
> about 1 or 2 cc - pre chamber that allows it to develop and then fire a much
> larger "Jet" into the main chamber.  Without this pre chamber, it simply
> becomes a warmer ignition and loses most - if not all - its benefits.
> 
> Second is pumping as much energy as possible into the plasma discharge phase.
> 
> Interestingly enough, Rail Gun technology has been miniaturized for this
> purpose.
> 
> Patent 4,487,192 references SAE Paper "Design of a Plasma Jet Ignition System
> for Automotive Applications"   SAE 776355 of 1977.  It describes the use of a
> 10 to 100 picofarad capacitor in parallel with an auxiliary spark gap and
> another firing gap - confined within a plasma chamber.
> 
>   To HV Ignition system
>      |
>      +------------------------------------+
>      |                                      |
>     v                                      |
>         (Auxiliary Gap)             |
>     ^                                     |
>     |                                  ---------
>     |                                  ---------
>    v                                      |
>       ( Plug Gap )                  |
>    ^                                      |
>    |---------------------------------------+
>  ----
>   --
>   -

Why two gaps, and not just one big gap?  Is the auxiliary gap in the
chamber also, or in a plug wire or something?


-- 
Steve Ravet
steve.ravet at arm.com
Advanced Risc Machines, Inc.
www.arm.com