Modeling Heat Loss through Piston and Effects of Thermal Boundary Coatings in Diesel Engine Simulations using Conjugate Heat Transfer models

Conference · Mon Oct 17 04:00:00 EDT 2016

DOI:https://doi.org/10.4271/2016-01-2235· OSTI ID:1395154

Kundu, Prithwish; Scarcelli, Riccardo; Som, Sibendu; Ickes, Andrew; Wang, Yan; Kiedaisch, John; Rajkumar, M

Heat loss through wall boundaries play a dominant role in the overall performance and efficiency of internal combustion engines. Typical engine simulations use constant temperature wall boundary conditions. These boundary conditions cannot be estimated accurately from experiments due to the complexities involved with engine combustion. As a result they introduce a large uncertainty in engine simulations and serve as a tuning parameter. Modeling the process of heat transfer through the solid walls in an unsteady engine computational fluid dynamics (CFD) simulation can lead to the development of higher fidelity engine calculations. These models can be used to study the impact of heat loss on engine efficiency and explore new design methodologies that can reduce heat losses. In this work, a single cylinder diesel engine is modeled along with the solid piston coupled to the fluid domain. Conjugate heat transfer (CHT) modeling techniques were implemented to model heat losses for a full cycle of a Navistar diesel engine. This CFD model is then validated against experimental data available from thermocouples embedded inside the piston surface. The overall predictions from the model match closely with the experimental observations. The validated model is further used to explore the benefits of thermal barrier coatings (TBC) on piston bowls. The effect of TBC coatings were modeled as a thermal resistance in the heat transfer models. Full cycle 3D engine simulations provide quantitative insights into heat loss and thus calculate the efficiency gain by the use of TBC coatings. The work establishes a validated modeling framework for CHT modeling in reciprocating engine simulations.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE) - Office of Vehicle Technology
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 1395154
• Country of Publication: United States
• Language: English