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Old 13th February 2008, 21:09   #181
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Hi TURBOSAM,

What I understood is

1)Heat is the Energy created in combustion by burning fuel & is converted into mechanical energy by pushing piston down.We want maximum of this heat energy to be converted into mechanical output.

2)But thats not the case,33% of heat energy is lost thorugh exhaust and in cooling.

3)By using wasted heat energy from exhaust for pre heating the intake charge,we are using otherwise wasted heat energy in more efficient manner.

4) Using hotter intake charge increases Thermal Efficiency of an engine as it doesnt absorb more heat from engine components thereby making them less cooler....so on next expansion stroke there is lesser amount of heat energy absorbed by engine components...hence more heat energy is available for mechaical conversion......so we are increasing Thermal Efficiency of an engine.....

5)With same amount of fuel we are getting faster pressure build up in expansion stroke hence faster piston downward movement in pre heated air fuel....

I m really learning so much....thanks for such detailed technical reply.....
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Old 18th February 2008, 09:44   #182
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Default thanks!

heating the fuel adds still more benifits!
use coolent by pass AND main line <separately> to heat the fuel just before entering the injectors.
the heat absorbed by the fuel will help automise the fuel much faster.
--- just before the injectors.. because if the system uses a return line for the fuel .. the repeated heating of extra fuel will drastically evaporate light fractions and heavy residual fuel will add the cold starting problem!

Quote:
Originally Posted by finetuning View Post
Hi TURBOSAM,

What I understood is

1)Heat is the Energy created in combustion by burning fuel & is converted into mechanical energy by pushing piston down.We want maximum of this heat energy to be converted into mechanical output.

2)But thats not the case,33% of heat energy is lost thorugh exhaust and in cooling.

3)By using wasted heat energy from exhaust for pre heating the intake charge,we are using otherwise wasted heat energy in more efficient manner.

4) Using hotter intake charge increases Thermal Efficiency of an engine as it doesnt absorb more heat from engine components thereby making them less cooler....so on next expansion stroke there is lesser amount of heat energy absorbed by engine components...hence more heat energy is available for mechaical conversion......so we are increasing Thermal Efficiency of an engine.....

5)With same amount of fuel we are getting faster pressure build up in expansion stroke hence faster piston downward movement in pre heated air fuel....

I m really learning so much....thanks for such detailed technical reply.....
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Old 18th February 2008, 09:58   #183
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Default hi gemi!

there is lot more than just the numbers..
wide band oils<0w40 5w 50> cost in multiples so unless u use a premimum car the manu. will not recomand the costly oil.
0 w 40 or 5 w 50 oils will definately reduce the oil pumping losses at lower temp.
as when itis cold it will act as if its 5 w oil
it will remain stable as it will behave as if its 50 w oil when hot.
u get much wider range of protection at much wider range of temp at much higher cost
if u need all round protection then stick to mobil 1 fully synthetic 15 w 50
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Originally Posted by gemithomas View Post
Just a few doubts. FIAT recommends 15W40. What will be the adverse effects and advantages of shifting to
1)5W40
2)5W50 (is it actually advisable to shift from the recommended '40' value to a '50'??)
3)0W40

WOuld really appreciate your help on this.
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Old 18th February 2008, 10:56   #184
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Actually 25-30% is the energy that is utilized by IC engines. The majority is lost in the exhaust.
Couldn't the exhaust pressure be used to charge the batteries (turbo like fan) or other accessories ?
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Old 20th February 2008, 08:34   #185
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Default hi srishiva!

actually only 30% of energy is available in pertol engines that too at wide open throttle and full load at max torque rpm.!!
in all other conditions , the efficiency is much lower @ 5-15%
if we use some mechanical energ converter.. like turbine to charge the alternator.. 1-the back pressure will increase the pumping losses of the engine 2-the alternator will need a re designing as the turbine rpm is around 80000-150000 rpm. the std alt will blow itself in seconds...
if we use the step down gears.. the cost will rise too..
its possible and being done in turbo prop engines.. but not for auto engines!!
stationary engines can use the exhaust heat in heat exchanger to pre heat some other material... water for boilers, furnace fuel, and sky is the limits.... but out of our scope as an auto engine!
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Originally Posted by srishiva View Post
Actually 25-30% is the energy that is utilized by IC engines. The majority is lost in the exhaust.
Couldn't the exhaust pressure be used to charge the batteries (turbo like fan) or other accessories ?
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Old 21st February 2008, 12:20   #186
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Default Can we use LPG vapouriser for vapourising fuel?

Hi TURBOSAM,

Heating fuel with hot coolent is good idea.

Can we use vapouriser of LPG gas kit for preheating petrol/diesel?.

It is also called pressure reducer.It gets heat from hot coolent.LPG is stored with some pressure in liquid form.With reduction in pressure to normal atmospheric it changes its state to gas before entering combustion chamber.
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Old 22nd February 2008, 08:28   #187
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Default definately!

easier and simpler and economical method will be a simple copper eubing wound over the metal fuel line .
and hot coolent which passes thrugh the cabin heating side flown through it .
as the cabin heating coolent line is tapped BEFORE the thermostat valve, the coolent is always hot and the temp variance is also less..PLUS a part of wasted hear is used for the regeneration!
the same way the same heated coolent then can be routed over a metal pipe of dia 2.5 to 3 inch and intake pipe is fitted to it. this will raise the temp of the intake air< heating air will drop the max power potential in all out effort>
heating fuel just before the injection will increase the power out put + increase the fuel efficiency in all terms. kmpl as well as kw/kg/hr
Quote:
Originally Posted by finetuning View Post
Hi TURBOSAM,

Heating fuel with hot coolent is good idea.

Can we use vapouriser of LPG gas kit for preheating petrol/diesel?.

It is also called pressure reducer.It gets heat from hot coolent.LPG is stored with some pressure in liquid form.With reduction in pressure to normal atmospheric it changes its state to gas before entering combustion chamber.
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Old 22nd February 2008, 20:01   #188
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Hi TURBOSAM,

Heating fuel before injectors requires efficient heat exchanger,because fuel is made up of so many different components we need such a heat exchanger where fuel gets sufficient heat to vapourise complete fuel particles.For that we need to have such design that allows fuel to rest inside such exchanger for sufficient time to get heated & vapourised.

Do look at this link...

BrightGreen Fuel Device Install
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Old 29th February 2008, 08:56   #189
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Default great..

this is exactly what i was trying to express..!!
this will definately help out in a great way.
one piece of caution..
heated diesel creates problems in countries like ours, because the addultrated diesel, when heated ,wash away the lubricating filme fron the fuel injection pumps.
some cars have closed lines.with return to tank function... restrictor s needed there.lke uno 1.2 siena 1.2
some cars have returnless fuel line <palio 1.6 stile >u dont need restrictor for it ..
... one friendly advice..!!!!
NEVER DESIGN , INSTALL A MOD. KIT OR ANY FITMENT IN SOMEONE ELSE'S CAR,GENERALLY IT BECOMES TOO POTENT TO HANDLE FOR THE POOR OWNER- HE BANGS..AND HIS RELATIVES TAKE UR A@#$!!!
Quote:
Originally Posted by finetuning View Post
Hi TURBOSAM,

Heating fuel before injectors requires efficient heat exchanger,because fuel is made up of so many different components we need such a heat exchanger where fuel gets sufficient heat to vapourise complete fuel particles.For that we need to have such design that allows fuel to rest inside such exchanger for sufficient time to get heated & vapourised.

Do look at this link...

BrightGreen Fuel Device Install
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Old 5th March 2008, 19:57   #190
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Default improving the aerodynamics!

drag is a major power sapping entity .
above 60 kmph it becomes progressively potent.
with properly designed ,and exucuated attachments to the vehicle<i mean proper, not fancy attachments!>significant fuel /power can be saved..
cd figures are totelly misleading ... for example cd of volkswagen combi<panel van like omni> has much lower cd than the jaguar racer of the same year.!!!!
but when u compare the real deag value< cd multiplied by the frontal area that is CdA> the combi is a real power sapper.
better front air dams, better real taper -vertical as well as at the sides- offers significant gains.
most of the wings, spoilers which are designed for the down force CREATE A LOT OF DRAG..
f1 cars have tremandous amount of drag as well as the down force< which saps lot of power and offers a lot of road holding. this again adds the rolling resistence ... which saps additional power!
ground effects <treatments on the underbody >can offer lot of aerodynamic aid without sapping power...

Last edited by TURBOSAM : 5th March 2008 at 20:01.
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Old 30th March 2008, 15:18   #191
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Default aerodynamics!

aerodynamics can provide valuable addition to the kms travelled per litre of fuel.
nderbody irregularities can and do cause significent amount of drag and the drag causes power to propel the vehicle ..
with better aerodynamics,, we can have same fuel efficiency for higher top speed, or we can save some fuel at the same speeed .
its one time investment and can reap life long benifits!!!
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Old 17th June 2008, 11:43   #192
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Default better cycles --

generally most of the petrol engines work on -otto-cycle ,
which is very much in efficient at part throttle .
one of the reasons the compresion ratio is same as expansion ratio.
in atkinson cycle and miller cycle the expansion ratio is longer than the compression ratio.. increasing the mechanical efficiency.its not very difficult to modify the otto cycle to atkinson cycle ... though peak power can be slightly lesser, low end torque is much higher improving the driving pleasure if properly done..
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Old 17th June 2008, 13:23   #193
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Quote:
Originally Posted by TURBOSAM View Post
in atkinson cycle and miller cycle the expansion ratio is longer than the compression ratio.. increasing the mechanical efficiency.
What do you mean by longer ratio?
Do you mean that the duration for expansion is longer?
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Old 18th June 2008, 16:11   #194
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Quote:
Originally Posted by Vinaygv View Post
Hi, with regard to additives in fuel and driving styles, this is something that I came across on the net while researching acetone. Please check this link. Makes some interesting while validating most of the ideas discussed on this thread.

Acetone In Fuel Said to Increase Mileage
This actually works. I have tried it on my sept 03 Santro Xing. First I switched from Speed to regular petrol. Then with the help of the link above, I calculated that 15-20 ml of Acetone per 10 Lt of petrol does make a noticable difference, not only in FE but in performance as well. The pickup has improved, noise and vibrations have reduced. I wanted to make sure that these conclusions are not "make-believe" types, so I followed the same gear shifting pattern and driving style for 3 fillings and the results were surprising. The improvement is @14%, not bad. Off course there are other factors as well, such as tyre pressure etc. But, for better results I would say do not cross 16-18ml/10 lt mark. More Acetone would not help to get the desired results.
P.S. these observations/findings are my own on my own car and are not representative in any manner.
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Old 18th June 2008, 17:51   #195
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During slow moving traffic, is it good to ride in 2nd gear with legs on half-clutch & brake as needed (or) in 1st gear? Which is good for engine life as well as FE?
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