SI Engine Calibration using GT Power

AIM 

       The objective of the project is to calculate the various parameters of the engine at a particular rpm for a single-cylinder engine.

        Increase the power output by 10% at 3600 rpm by varying different parameters of the engine.

PROCEDURE 

        The GT Power has various tutorial files that are used to find the results depending on our requirements. 

        The single-cylinder port injection engine is used for our purpose and save the file. Tutorials --> Engine performance --> 01-1 cylDlorSl --> 1 cylSl-final.gtm.

        The emission parameter of the engine such as NOx, CO is added for the simulation using Cylinder -->  Combustion object --> Comb --> Advanced --> NOx reference and CO reference separately.

       Then the plot which is required for the results is selected under the cylinder block.                                       Flow - Pressure, Pumping loss, P-V Diagram, Volume, Valve mass flow & lifts.                                     Thermal - Temperature, heat transfer rate.                                                                                       Combustion - Burn rate, In-cylinder energy balance.                                                                         Composition - NOx concentration. 

      Select the F4 option to open the case set up to add more cases use option Cases --> Append cases.

The select run option to run the simulation and unselect the Run each case in parallel option and select the show the graphical user interface under simulation option and confirm it by clicking the finish option and the simulation starts to run.

Outputs

 The first table denotes the value for the 1800 rpm.

   BSFC - It is the rate of fuel consumption divided by the power produced.

   BMEP - The Mean effective pressure calculated from the torque generated at the crankshaft.

   IMEP - It is the average pressure, that induced in the combustion chamber during the complete thermodynamic cycle.

   FMEP -  It is defined as the Mean Effective Pressure lost due to the friction. 

                                        FMEP = IMEP– BMEP

BMEP = IMEP - FMEP 

          =  10.41- 1.13

          = 9.28 bar.

2. Increase the power output by 10 % at 3600 rpm.

The power output can be increased by these factors

i) Compression ratio - Ratio of maximum cylinder volume divided by minimum cylinder volume. The increase in CR value can cause a knocking effect in the engine which will damage the engine so it is not changed.

ii) Geometry - The bore dia value of the engine is increased.

iii) Duration - The time taken for the combustion is reduced to raise the power output but it has an effect on the emission.

iv) Fuel ratio - The effective air to fuel ratio by decreasing the value increases the fuel consumption for the engine.

Case setup 

Engine Output 

RESULTS

       The power output of the engine is increased by 10% by increasing bore dia, decreasing duration time and fuel ratio. The Brake power increased by 24.5 from 21.9 bar by varying the above parameters.