If you like off beat engines...

Take a look at this:
http://www.fairdiesel.co.uk/

In article
,
bildan wrote:

Take a look at this:
http://www.fairdiesel.co.uk/

A Diesel version of the cam engine! This engine was certificated (in
gasoline version) in 1946 and was tested in a Piper Arrow, IIRC, in the
1980s.

I saw one of these run at a fly-in in Southern California about that
time -- it had a 4-blade prop attached and sounded like a baby Merlin.

I do not know the results, but I have seen some engineering materials
analysis, which indicates that it pushes the stress limits of some major
components -- namely the main cam followers, which drive the pistons. I
would think that a Diesel version would place even higher stress on
these components than a gasoline version would.

The design is intriguing and would offer a very low frontal area and
incredible smoothness. I think that it would have to be water-cooled,
due to its compactness -- air-cooling would be next to impossible.

--
Remove _'s from email address to talk to me.

On Jan 27, 9:27*pm, Orval Fairbairn
wrote:
In article
,

*bildan wrote:
Take a look at this:
http://www.fairdiesel.co.uk/

A Diesel version of the cam engine! This engine was certificated (in
gasoline version) in 1946 and was tested in a Piper Arrow, IIRC, in the
1980s.

I saw one of these run at a fly-in in Southern California about that
time -- it had a 4-blade prop attached and sounded like a baby Merlin.

I do not know the results, but I have seen some engineering materials
analysis, which indicates that it pushes the stress limits of some major
components -- namely the main cam followers, which drive the pistons. I
would think that a Diesel version would place even higher stress on
these components than a gasoline version would.

The design is intriguing and would offer a very low frontal area and
incredible smoothness. I think that it would have to be water-cooled,
due to its compactness -- air-cooling would be next to impossible.

--
Remove _'s *from email address to talk to me.

One thing about the opposed piston configuration is that it spreads
the loads from one power stroke over two cam followers. If the power
ramps on the cams are very steep, maybe the loads could be minimized.
Ultimately, it's about how much torque you can ask it to produce.

One thing I like is the pistons can be held at TDC for the whole
injection interval. That removes one of the big issues for high RPM
diesels.

On 28 Jan, 04:46, bildan wrote:
On Jan 27, 9:27*pm, Orval Fairbairn
wrote:

In article
,

*bildan wrote:
Take a look at this:
http://www.fairdiesel.co.uk/

One thing I like is the pistons can be held at TDC for the whole
injection interval. *That removes one of the big issues for high RPM
diesels.
They mention an improvement in efficiency is possible
but don't give any numbers. I suppose that for an essentially
fixed speed application such as an aircraft engine the cam
profile could be selected to optimise efficiency at that speed.

Interesting.

On Feb 3, 8:48*am, bod43 wrote:
On 28 Jan, 04:46, bildan wrote:

On Jan 27, 9:27*pm, Orval Fairbairn
wrote:
In article
,

*bildan wrote:
Take a look at this:
http://www.fairdiesel.co.uk/
One thing I like is the pistons can be held at TDC for the whole
injection interval. *That removes one of the big issues for high RPM
diesels.

They mention an improvement in efficiency is possible
but don't give any numbers. I suppose that for an essentially
fixed speed application such as an aircraft engine the cam
profile could be selected to optimise efficiency at that speed.

Interesting.

....the dyna cam engine, which is what the diesel design is based on,
was originally designed during WW2 to power torpedoes. ergo, when
first designed, component life was not an issue beyond a minute or
so... and anyone with a father, uncle or grandfather who sailed on ww2
pig boats who passed down war stories will attest to how reliable our
torpedoes weren't. pat wilks and dennis palmer formed a corporation
during the 80s to develop the technology for light aircraft, and flew
an Archer around to airshows to promote it. Then they got into a pi$
$ing match with a company call axial vector technologies (originally
over licensing the technology to axial), and lost the right to further
develop (or for that matter even talk about) the engine.

bottom line: very smooth, tons of torque at 1800 - 2000 rpm (and 200
horsepower), nice exhaust note, but also very heavy and with
substantial cooling problems that were never remedied.

wrote

passed down war stories will attest to how reliable our
torpedoes weren't. pat wilks and dennis palmer formed a corporation
during the 80s to develop the technology for light aircraft, and flew
an Archer around to airshows to promote it. Then they got into a pi$
$ing match with a company call axial vector technologies (originally
over licensing the technology to axial), and lost the right to further
develop (or for that matter even talk about) the engine.

Reply to above post, from Jim:
The major problem with the torpedoes were the fact that they would not go
"boom" when they got to the target, not the engines.

Yes, there were some engine problems, but they were reliable enough.
--
Jim in NC

On Feb 3, 3:46*pm, "Morgans" wrote:
wrote

passed down war stories will attest to how reliable our
torpedoes weren't. * pat wilks and dennis palmer formed a corporation
during the 80s to develop the technology for light aircraft, and flew
an Archer around to airshows to promote it. *Then they got into a pi$
$ing match with a company call axial vector technologies (originally
over licensing the technology to axial), and lost the right to further
develop (or for that matter even talk about) the engine.

Reply to above post, from Jim:
The major problem with the torpedoes were the fact that they would not go
"boom" when they got to the target, not the engines.

Yes, there were some engine problems, but they were reliable enough.
--
Jim in NC

Torpedo engines and the Dynacam have very little in common with this
engine except that they fall in the general category of "barrel
engines". That's like saying the little 3-cylinder Anzani and the
mighty R4360 were the same because they were both "radials".

The Fairdiesel is an opposed piston, 2-stroke diesel. That puts it in
the category of the Fairbanks Morse OP diesels and the Junkers Jumo
205 aircraft engines. The Fairdiesel had the added advantage that the
intake and exhaust port timing and port duration can be non-
symmetrical and highly optimized. Also the piston travel at "TDC" can
be delayed while the fuel injection happens. The Fairdiesel is a
theoretical masterpiece.

The only question is the durability of the cam followers at some
specified torque. That will require some testing to prove.

In article ,
"Morgans" wrote:

wrote

passed down war stories will attest to how reliable our
torpedoes weren't. pat wilks and dennis palmer formed a corporation
during the 80s to develop the technology for light aircraft, and flew
an Archer around to airshows to promote it. Then they got into a pi$
$ing match with a company call axial vector technologies (originally
over licensing the technology to axial), and lost the right to further
develop (or for that matter even talk about) the engine.

Reply to above post, from Jim:
The major problem with the torpedoes were the fact that they would not go
"boom" when they got to the target, not the engines.

And secondarily, problems with running at the proper set depths.

Yes, there were some engine problems, but they were reliable enough.