Week 11: Project 2 - Emission characterization on a CAT3410 engine

AIM:- To simulate, analyze, and compare the significances of both omega and open w pistons

INTRODUCTION:-

In this project, I will demonstrate the diesel engine simulation and the characteristic difference between open w type piston and omega type piston.

The simulation will be a close sector analysis with a 60-degree angle and this includes on fuel injector nozzle.

THEORY:-

I will illustrate the step-by-step procedure to construct a complete setup to begin and analyze the simulation.

GEOMETRY :-

• In this analysis, I have performed simulation on close sector surface/geometry.
• To make the sector surface we need the geometry file. By using the "Make engine sector surface" tool we can create a surface file.
• To extract the sector files, upload the surface file in the below-shown dialog box and click on extract.
• A set of files are generated in the directory as shown in the second picture.

Diagnosis :-

Case Setup :-

• The above picture shows the crank angle-based IC_Engine setup. The values for this setup are provided in the challenge section.
• In the reference field initially, the ID's are not available we should flag the boundaries and name them in order to get the paths in the reference section.
• I have flagged the boundaries prior to setting up or feeding the values into the application dialogue box.

Crank angle -based :-

MATERIALS:

There are a couple of options to be enabled in this section.

1. Parcel Simulation.
2. Reaction Mechanism.
3. Species.

After enabling the above parameters, start setting up the section.

Gas simulation :-

Use the default options for this parameter. However, we will be using atmospheric air with fuel.

Parcel simulation :-

Global transport parameters :-

Reaction mechanism :-

It is always advisable to set up a reaction mechanism before setting up the parcel simulation. As we may not find the option we should enable.

• In the reaction mechanism, upload the mech.dat file and check properties. Initial this will show some error because the mechanical files that contain the species in the mech.dat are incomplete without thermodynamic properties.
• So, there will be another file called therm.dat. We can upload the input file by File-> Import -> Import Input File(s) and here upload the desired file.
• Now check the properties, This time the reaction mechanism shows zero errors.

Species :-

• In species, enable the parcel option and add the DIESEL2 species as shown in the below picture.
• To introduce a new species click on the "PLUS" button on the right side and enter the title.
• With this, the Material setup is completed.

Gas Simulation :-

Simulation time parameters :-

• The starting and ending time is -147 degrees and 135 degrees respectively.
• For other values, I have followed the information provided on the challenge page.

Solver parameters :-

• In solver, parameters use the density-based Navier-Stokes solver.

Boundary Flagging :-

• There are few boundaries in this geometry compared to the complete IC_Engine simulation.

• In piston boundary conditions check the piston motion option.

Regions and initialization :-

• In this simulation, as this is a close sector analysis we have only one region.

Spray modeling :-

Combustion modeling [SAGE/Adaptive zoning] :-

• In this combustion modeling, I have used the SAGE model by using the values provided on the challenge page.

Emissions modeling :-

Turbulence modeling[RANA_K_EPS_RNG] :-

Base grid :-

Adaptive Mesh Refinement :-

• I have used AMR for temperature and velocity in intake ports 1 & 2, and cylinder head.

Fixed embedding :-

Post Variable Selection :-

Output Files :-

Plotting :-

Pressure

Volume(m^3) :-

Max_Temp :-

Max_Pres :-

Mass :-

Kin_Visc (m^2/s) :-

Integrated_HR :-

HR_Rate :-

Dyn_Visc :-

C_v :-

C_p :-

Base Grid:-

• The rough cell count is estimated for the open-W piston to be 6073 cells.
• The rough cell count is estimated for Omega piston to be 6736.38 cells.