Date post: | 02-Jan-2016 |
Category: |
Documents |
Upload: | whoopi-cohen |
View: | 47 times |
Download: | 2 times |
California Maritime California Maritime AcademyAcademy
EPO 220 Diesel Engineering I
Fuel Injection & Combustion Chamber Design
Material Compiled by Robert Jackson
Diesel Engine Combustion Chambers
Combustion chambers are designed to promote air turbulence which helps atomize the fuel in preparation for combustion.
Modern diesel engines typically utilize an openopen type combustion chamber.
Though not commonly used today, the following chamber designs were utilized in the past to promote complete combustion: Turbulence Chambers Precombustion Chambers Energy Cell or Air Cell Chambers
Air Turbulence in the Combustion ChamberA- Intake Stroke; B-Compression Stroke;
C-Power Stroke; Exhaust Stroke
Diesel Engine With Open Combustion Chamber
Typical Open Combustion Chamber Design
Hemispherical Type Open Combustion Chamber
M Type Open Combustion Chamber
Precombustion Chamber
Precombustion Chamber The precombustion chamber is connected to the
piston clearance volume by one or more passages.
This chamber may be located in the head or cylinder wall.
A precombustion chamber will hold 25 to 40 percent of the total clearance volume.
Because of the larger surface area of the combustion chamber, heat losses are increased and thermal efficiency decreases.
The precombustion chamber promotes smooth combustion and improves engine performance at low loads.
Mercedes Diesel
With Precombustion Chamber
& Glow Plug
Removable Injector plus Precombustion Chamber Combination
(Caterpillar Tractor Co.)
SEMT Pielstick Variable Geometry Combustion Chamber
Turbulence Chamber
Turbulence Chamber The turbulence chamber is very similar in design to the
precombustion chamber. The principal difference between the two designs is the amount of chamber volume compared to the clearance volume of the main combustion chamber.
Engines utilizing turbulence chambers have very small clearance volumes.
When the piston reaches TDC virtually all of the available air has been compressed in the turbulence chamber.
The chambers are usually spherical in shape and are incorporated into either the head or cylinder.
The opening through which the air must pass becomes smaller as the piston reaches the top of the stroke, thereby increasing the velocity of the air in the chamber.
Waukesha Engine Turbulence Chamber
Lanova Energy Cell
The Lanova Energy Cell The energy cell is a combination of the
precombustion chamber and turbulence chamber designs.
The Lanova system has two rounded combustion spaces shaped like a figure 8.
The fuel is injected in a pencil stream, passing directly across the narrow throat of the combustion chamber so most of the fuel enters the energy cell.
Most of the fuel entering the energy cell is trapped in the small inner cell, but a small portion passes into the outer cell where it meets with a sufficient quantity of super-heated air to explode violently.
Combustion Sequence in the Lanova Energy Cell
System
The nozzle injects fuel in a pencil stream which penetrates into the
energy cell. Partial combustion takes place inside the energy cell radically raising cell pressure. High pressure
gasses exiting the energy cell through the venturi throat cause high turbulence levels in the main combustion chamber
promoting good combustion.
Pintle & Hole Type Fuel Injector Nozzle
Operation Of Fuel Injection Nozzle
Angular Difference Between Needle Face & Injector Seat
Fuel Injectors
Fuel Line Pressure (lower line) & Needle Lift Diagrams
a) At high load
b) At low load
Injector Nozzle Tip for the Mak
Mak Fuel Injector With Oil Cooling
Sulzer RND-M InjectorNon-Recirculating Type, Water Cooled
Fuel Injector Hold Down Bolt
Tensioning Washer Disk Stack
Sulzer Fuel Injectors
Low Sac Volume Fuel Injection Nozzle Tip
Injector Tip Advances To Minimize Sac Volume
Port & HelixHigh-Pressure
Fuel Pump
Effective Stroke of the Port & Helix Pump
Port & Helix High-Pressure
Fuel Pump
Illustration showing pump plunger, barrel,
delivery valve, & control rack for
adjustment of pump effective stroke
Exploded View of the
Port & Helix Fuel Pump
High-Pressure Fuel Pump &
Camshaft Follower For
Mak 6M 322 Diesel Engine
High-Pressure Fuel Pump Timing
Balance Delivery Valve Utilized on
Mak 6M 322 Diesel Engine
MAN B&W K98MC Slow-Speed
Crosshead Diesel Engine
Bore 980mmStroke 2660mm
94 Rpm Maximum6 to 12 Cylinders
5,720 kW Per Cylinder
12 Cylinder Engine Produces 68,640 kW
(93,360 BHP)
MAN B&WSlow-Speed Diesel Engine
High-Pressure Fuel Pump
MAN B&W Fuel Pumps
B&W Slow-Speed Diesel Engine High-Pressure Fuel
Pump With Variable Injection Timing
B&W High-Pressure Fuel
Pump
B&W High-Pressure
Fuel Pump
Fuel Pump Shock
Absorber
The Modern Slow Speed Diesel Engine
Sulzer RTA84C
Diesel Engine
Sulzer Fuel Pump Placement
Sulzer RTA84T High-Pressure Fuel
Pump
RTA Camshaft, Valve Actuators, & High Pressure
Fuel Pumps
Sulzer Valve Controlled
High-Pressure Fuel Pump
Spill Valve Cut-away Illustration
Sulzer High-Pressure Fuel Pump Block1 Cover
2 Cylinder
3 Piston
4 Slide Ring
5 Viton-ring
6 Conical Clamp Ring
7 Spring
8 Spring Plate
9 Spindle
10 Guide Bush
11 Rubber “O” Ring
12 Suction Valve
13 Rubber “O” Ring
14 Yoke
D Delivery Valve
U Spill Valve
S Suction Valve
D –Delivery ValveD –Delivery Valve
U -Spill ValveU -Spill Valve
S -Suction ValveS -Suction Valve
10 –Connecting 10 –Connecting piece for high piece for high pressure fuel pipepressure fuel pipe
11 –Tension Bolt11 –Tension Bolt
30 –Cover for 30 –Cover for suction & Spill Valvesuction & Spill Valve
31 –Rubber Ring31 –Rubber Ring
32 –Relief Valve32 –Relief Valve
33 –Guide Bush33 –Guide Bush
34 –Push Rod34 –Push Rod
35 –Spring35 –Spring
36 –Locking Wire36 –Locking Wire
37 –Pressing Nipple37 –Pressing Nipple
Fuel Pump Effective Stroke Without Variable
Injection Timing
Sulzer Safety Cut-Out Device
Constant Volume or “OTTO” Cycle
Dual Cycle
The Stroke Based Indicator Card
Typical Indicator Diagram (crank-angle based)
Indicator Card Showing Retarded Ignition Due to Low
Quality Fuel
Example of Retarded Ignition
Variable Injection Timing
Characteristics
Fuel Pump Effective Stroke With Variable
Injection Timing
Fuel Pump Linkage
Port & Helix High-Pressure
Fuel PumpWith Variable
Injection Timing
MAN B&W Fuel Pumps
MAN B&WHigh-Pressure
Fuel Pump
MAN B&WMedium Speed Diesel Engine
L32/40
Variable Injection Timing Used On L32/40 Medium-Speed Diesel Engine
Wartsila Split High-Pressure Fuel Pump
Wartsila Split Pump Operation
For description of pump operation see “Wartsila 64 Technical Review” pp 14
Typical Heavy
Fuel Oil
System
Nozzle Tip Fuel Circulation
Nozzle Fuel Circulation
Sulzer Circulating Type
Injectors
B&W Circulating Type Fuel Injector
B&W Cylinder Cover
Showing High-Pressure
Pipes & Fuel Injectors
Unit Type
Fuel Injector
Distributor Type Fuel Injector System