Hi Paul,
Having read your website,
There are a number of WHATIF flies buzzing around my head if you would
be kind enough to swat them for me for a good night sleep.
1. "It takes HP to suck the combustion air into the engine" .
Does that mean you simply allow more air to go to the combustion chamber
with no MORE EXTRA in FUEL resulting in greater output HP ?
1a) By Output Horsepower my understand is the flywheel will achieve
1000rpm in less time and the flywheel will overcome friction/resistance
using same amount of fuel.
2. If my above assumption of more air no extra fuel is correct then an
ECU like Megasquirt simply continues to squirt (using direct
injection) same amount of fuel into the combustion chamber and firing
the spark at the appropriate time ?
3. To harness the extra Horse Power and rev up the engine you suggested
using the new side throttle system with p-port. Does that mean the using
VERNIER CONTROL Is that the new throttle cable. But I am wondering there
must be some sensor which tells the ECU as you pull the cable to allow
more air fuel into the combustion before the usual sparking ?
4. As far the Megasquirt is concerned should it continue to behave same
usual
even if the engine wasn't p-ported with reference to amount of fuel to
squirt and then spark.
5. If my aircraft has an all in weight of 450kg including engine,pilot,
wallet . I have fuel tank of say 80 litres. I want the fuel to last as
long as possible which engine should I use 13b , 13b P-port, 13b Turbo ,
16b , 16b P-port , 16b Turbo , 13b Turbo Compound or another option ?
Regards
Zahid Rahman
1. The fuel air ratio must be maintained. It all has to do with BSFC.
Brake Specific Fuel Consumption. This is the weight of fuel burned per
HP out of the engine. Google BSFC.
1a. Yes the engine will accelerate faster but HP is not the only factor.
Rotating inertia is a major factor.
2. Mega Squirt maintains the correct fuel air ratio.
3. A slide throttle reduces in internal aerodynamic drag of the intake
system.
4. Same answer as 2. The sensor is either a mass airflow sensor or
simply the intake manifold pressure and air temperature.
5. For best BSFC use a turbo compound RX8 engine. Soon to be available
from Mazda. May not be P-port so a lower BFSC would be possible with a
turbo compound P-port.
Paul Lamar
When is it appropriate to use reduction ratios 2.85 and when should one
use 3.17.
The reverse rotation also available with Ford of 2.17:1 and 1.85:1 , is
it used with piston engines because they turn in the opposite direction
to the rotary.
Zahid Rahman
HP is RPM times torque.
Most aircraft piston engines turn in the same direction as the rotary.
Are you a pilot?
Paul Lamar
Not yet. I going to build my own light aircraft as a hobby. I asked the
question because I thought it said on your website the rotary engine
turn in opposite direction and uses 2.17 reduction ratio.
Zahid Rahman
The Mazda engine rotates the same direction as most AC engines rotate.
Paul Lamar
Hi Zahid, I am building an LSA aircraft, I am using a single rotor 13b
sideported, you will probably want to use the alloy side plates from
Racing Beat in the US. The alloy plates will save a considerable amount
of weight. At 450Kgs if you are a two seat aircraft you will want to be
fairly weight conscious. If you use a single rotor, side porting would
seem the way to go. You will have to find someone to machine the e shaft
as they are not available off the shelf. You should have no difficulty
in producing 120Hp The less Hp you require the less fuel you will burn.
Large savings in fuel burn can be achieved by building the right plane
for your needs. In the LSA Field there are some very efficient aircraft
around. Andrew. CampBell
A side port single rotor is definitely not the way to go.
Paul Lamar
Is it a typo ?
Andrew Campbell wrote "If you use a single rotor, side porting would
seem the way to go."
Then Paul Lamar wrote "A side port single rotor is definitely
*not* the
way to go."
Regards
Zahid
Let me put it another way.
"A side port is definitely
*not* the way to go."
You would not introduce needless aerodynamic drag to the outside of your
air plane so why introduce needless aerodynamic drag to the inside of
your intake manifold?
Air velocity inside an intake manifold is up to 400 MPH.
Paul Lamar
Hi Paul,
Point taken about the intake drag.
Andrew.
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