This chapter investigates the computational fluid dynamic (CFD) simulation of diesel engine cold flow behavior at the speed of 2400 rpm. In this investigation, a three-dimensional (3D) combustion chamber model with an inlet and exhaust port was developed using the numerical tool. The dynamic meshing was done for different piston positions, inlet, and outlet valves operation for the entire range of the engine cycle (0°-720° crank angle (CA)). The standard k-ε turbulence model was used for CFD analysis to observe velocity, pressure, and temperature distribution. The entire process is highly complex, which requires more computational time with the powerful machine. The numerical simulation was carried out using a high-performance computing (HPC) system with 16 parallel cores and a 100 GB memory machine. The result shows the outstanding in-cylinder flow behavior, velocity, temperature, pressure, and turbulent kinetic energy for the diesel engines. The outcome of this study will be helpful to the engine designers for designing a fuel-efficient engine combustion chamber with minimum emission. © 2019 Elsevier Ltd. All rights reserved.