SI final
A single cylinder SI engine model has been prepared using the tutorial file and few parameters have been discussed below.
The tempelate End Environment is used to define the ambient pressure and temerature boundary conditions. The object env-inlet has one part env-inlet-1 and the object env-outlet has one part env-outlet-1.
The pipe round template has two objects int-runner and exh-runner which represent the intake manifld and the exhaust manifold. The diameter and length of the intake manifold is 40 mm and 350 mm respectively. The exhaust manifold has a length of 30 mm and 150 mm.
The pipe round template has two more objects int-port and exh-port which is used for intake port and exh-port.
The intake valve and the exhaust valve are shown on the GT-map with various valve profiles has shown in the figure below:
The cam angle time for the intake port is given by 239 and for the exhaust valve is given by 126. The flow coeffecients for the intake port and the exhaust port is given by valve flow lab experimental analysis which is then inputed into the GT.
The eng-cylinder engine cylinder template is used to represent the cylinders in the engine based on the number of cylinders in th engine. The inital state reference object is for the engine is given as 300K and 100kPa. It is also in various objects as well. Intrunner, Intport, cranktrain and cylinder. The reference objects are used to show the initial conditions inside the cylinder. The htr reference object is used to represent the heat transfer taking place inside the cylinder walls. The twall is used to specify the temperature of the cylinder head, cylinder and piston The combustion object is used to carry out the combustion phenomena.
The engine crank train is used to represent the engine speed, and other engine specifications. The engne bore and stroke is given as 86 and 86.07. The compression ratio of the engine is given as 9.5. All these things are specified in the refernce object geom.
The engine was run at 1800 rpm to check various parameters.
The BMEP of the engine was found out to be 9.74 bar.
The air flow rate through the intake valve is given as 458.04mg/cycle
The BSFC comes out be 239.17 g/kW.h
The in cylinder pressure variation according to the cycle.
The second case the engine was run at 3600 rpm and The power output came out to be 16.79kW.
The goal is to improve the performance output by tuning the engine parameters.
The engine bore and stroke size was changed to 87 and 87.5 and the compression ratio was changed to 12 inorder to increase the power output b 10%. the power outputput for the modified engine comes out to be 18.35 which is a good improvement with minimal and realistic.