A PRESENTATION ON “TRANSONIC ENGINE” Presented To: Presented By: Chhabile Sharan Bansal Assistant Professor 11EVVME018 Department of Mechanical Engg. B.Tech IV Year VIII Sem.
Transcript
1. A PRESENTATION ON TRANSONIC ENGINE Presented To: Presented
By: Chhabile Sharan Bansal Assistant Professor 11EVVME018
Department of Mechanical Engg. B.Tech IV Year VIII Sem.
2. CONTENTS Introduction Transonic combustion Transonic engine
principle Transonic combustion technology Ignition timing the key
Common rail system Supercritical Fuel and injection system The
comparison of liquid and supercritical fuel Taking aim at gas
guzzlers Benefits of TSCi engine Pollution chart conclusion
3. Spark ignition gasoline engine efficiency is limited by a
number of factors; these include the pumping losses that result
from throttling for load control, spark ignition and the slow burn
rates that result in poor combustion phasing and a compression
ratio limited by detonation of fuel. A new combustion process has
been developed based on the patented concept of injection-ignition
known as Transonic Combustion or TSCi; this combustion process is
based on the direct injection of fuel into the cylinder as a
supercritical fluid. Supercritical fuel achieves rapid mixing with
the contents of the cylinder and after a short delay period
spontaneous ignition occurs at multiple locations. Multiple
ignition sites and rapid combustion combine to result in high rates
of heat release and high cycle efficiency. The injection-ignition
process is independent from the overall air/fuel ratio contained in
the cylinder and thus allows the engine to operate un-throttled.
INTRODUCTION
4. TRANSONIC COMBUSTION The stratified nature of the charge
under part load conditions reduces heat loss to the surrounding
surfaces, resulting in further efficiency improvements. The short
combustion delay angles allow for the injection timing to be such
that the ignition and combustion events take place after TDC. This
late injection timing results in a fundamental advantage in that
all work resulting from heat release produces positive work on the
piston. Other advantages are the elimination of droplet burning and
increased combustion stability that results from multiple ignition
sources. Engine test results are presented over a range of speed,
load and operating conditions to show fuel consumption, emission
and combustion characteristics from initial injector and combustion
system designs. The results are correlated with thermo-dynamic
modelling and comparisons are made with contemporary engines.
5. TRANSONIC ENGINE PRINCIPLE Transonic engine is based on the
principle of the fuel injection. In transonic engine ignition
system is removed and redesigned the fuel injection. fundamentally
new fuel injection technologies that enable conventional internal
combustion automotive engines to run at ultra-high efficiency. By
operating high compression engines that incorporate precise
ignition timing with carefully minimized waste heat generation,
Transonic Combustion may have a transformational technology-one
that can achieve double efficiency compared to current gasoline
powered vehicles in urban driving. In turn, the companys products
also may significantly reduce fossil fuel consumption and GHG
emissions.
6. THE TRANSONIC COMBUSTION TECHNOLOGY The Transonic Technology
provides a heated catalysed fuel injector for dispensing fuel
predominately or substantially, exclusively during the power stroke
of an IC engine. This injector lightly oxidizes the fuel in a
supercritical vapour phase via externally applied heat from an
electrical heater or other means. The injector may operate on a
wide range of liquid fuels including gasoline, diesel and various
bio fuels. The injector fire at room pressure and up to the
practical compression limit of IC engines. Since the injector may
operate independent of spark ignition or compression ignition, its
operation is referred to herein as injection-ignition.
7. To minimise friction losses, the transonic engineers have
steadily reduced the compression of their test engines to between
20:1 and 16:1, with the possibility of 13:1 for gasoline engines.
There may be some advantage to going a little higher, but the
developers had tried to keep the fuel system within the range that
OEMs understand. The fundamental problem is that on average about
15% of the energy from the gasoline you put into your tank gets
used to move your car down the road . The rest of the energy is
lost to engine and driveline inefficiencies and idling. Normal
engines runs with rich air to fuel ratios, which also results in
fuel being trapped in the crevice as well as partially combusting
near the cylinder walls, this energy loss is the core of automotive
inefficiency
8. IGNITION TIMING THE KEY SC fluids have unique properties.
For a start, their density is midway between those of a liquid and
gas, about half to 60% that of the liquid. They also feature the
molecular diffusion rates of a gas and so can dissolve substances
that are usually tough to place in solution. SC fluid has a very
low surface tension. This enables quicker mixing, and it exhibits
catalytic activity that is two to three orders of magnitude faster
than the purely liquid form of the substance. If we eliminates the
time it takes to vaporize fuel and the heat lost with contact with
the cylinder walls, we could improve the base efficiency of an
engine. It is been figured that by changing the ignition delay so
the fuel ignited in that area, the flame can be kept away from
contact with the walls, which take heat out the engine.
9. COMMON RAIL SYSTEM In this system a high pressure pump
supplies fuel to fuel header as shown. the high pressure in the
header forces the fuel to each of the nozzles located in the
cylinders. At the proper time a mechanically operated (by means of
push rod and rocker arm) valve allows the fuel to enter the
cylinder through nozzle.
10. SUPERCRITICAL FUELAND INJECTION SYSTEM A comparison of
standard direct injection of liquid fuel and transonics novel
supercritical injection process (as viewed through an optical
engine fitted with a quartz window) shows that the new TSCi fuel
delivery system does not create fuel droplets.
11. THE COMPARISON OF LIQUID AND SUPERCRITICAL FLUID Throughout
the history of internal combustion engine, engineers have boosted
cylinder compression to extract more mechanical energy from a given
fuel-air charge. The extra pressure enhances the mixing and
vaporization of the injected droplets before burning.
12. When people think about reducing gasoline consumption,
alternative-fuel and hybrid cars usually come to mind. A
superefficient fuel injector designed to integrate easily into
conventional cars. Unlike standard fuel injectors, the TSCi
injector pressurizes and heats gasoline to 400 degrees Celsius,
bringing it to a supercritical state that is partway between liquid
and gas. When the substance enters the combustion chamber, it
combusts without a spark and mixes with air quickly, allowing it to
burn more efficiently than the liquid droplets produced by standard
injectors. A Transonic test car the size and weight of a Toyota
Prius achieved 64 miles per gallon at highway speeds, compared with
the 48 mpg highway rating on the Prius. Transonic is working with
three major automakers and expects the first TSCi-equipped vehicles
to hit the market in 2016. Multi Tasker Transonic is testing its
10.5-inch-long injector with ethanol, biodiesel, and vegetable oil,
in addition to gasoline. TAKING AIM AT GAS GUZZLERS
13. BENEFITS OF TSCi SYSTEM Improved fuel efficiency Lower
green house emission Multi-fuel compatible Economical OEM
Powertrain integration Near term adoption Global automotive
industrial sustainability Energy independence
14. POLLUTION CHART
15. CONCLUSION If it works as promised, the transonic
combustion engine technology would improve fuel economy by far more
than other options, some of which can improve efficiency on the
order of 20 percent. It is expected to cost about as much as high
end fuel injection systems currently on the market.