Hello, A yearly allocation for the LCRC cluster has been requested with the following updated information: Submitter/PI: Sibendu Som Project Name: dual-fuel-sprays Division: ES Project title: Supercritical Fuel Injection at Diesel Conditions and Gasoline direct injection transient characterization Associated funding: DOE - University FOA Other Systems: University of Alabama Science: Fuel injection is a crucial process in internal combustion engines that determines the subsequent steps of fuel/air mixing, ignition, heat release and emission formation. Under typical diesel engine conditions with high pressure injection, liquid fuel is usually injected at sub-critical temperature and supercritical pressure, into a chamber with temperature and pressure both higher than the fuel critical properties. Depending on the path through which the fuel/air mix, the liquid fuel could remain in the sub-critical condition with well-defined liquid/gas interface, or becomes supercritical where diffusive mixing dominates. While for Gasoline direct injection (GDI), the injection pressure is usually relatively lower and the chamber is at cooler, lower pressure conditions. Therefore atomization and drop breakup are crucial to the fuel/air mixing. This project will use a Computational Fluid Dynamics (CFD) software called Converge to model fuel injection process, to st udy the impact of fuel properties, ambient conditions and injector geometry on the fuel/air mixing process, in the context of diesel fuel injections, as well as GDI sprays. Project description: In the previous year, a real fluid thermodynamic and transport properties model was developed at University of Alabama. This model will be implemented with the commercial software Converge and used to study fuel injection at diesel conditions. An Eulerian-Eulerian mixture model will be used for the two phase flow simulation. The CFD model will be validated with experimental data taken from a constant pressure flow rig (CFR) operated at conditions covering from subcritical to supercritical conditions, and it is expected to provide more understandings about the transition from subcritical to supercritical mixing. For GDI sprays, a VOF-PLIC model with large eddy simulation (LES) will be applied to track liquid-gas interface and the transient behavior at needle opening will be focused on. A real injector geometry with manufactural details acquired by x-ray scanning will be compared with nominal geometry, to shed more insights on the impact of non-ideal struc ture on the downstream instability development and drop disintegration. Industry partnership: Project URL: http://www.transportation.anl.gov/engines/multi_dim_model_home.html Current FY Hours Used: undetermined amount New FY Requested allocation: 800000 Q1: 200000 Q2: 200000 Q3: 200000 Q4: 200000 Justification: Our recent publication (J. Kodavasal, K. Harms, P. Srivastava, S. Som, S. Quan, K.J. Richards, M. Garcia, “Development of stiffness-based chemistry load balancing scheme, and optimization of I/O and communication, to enable massively parallel high-fidelity internal combustion engine simulations,” Journal of Energy Resource Technology; JERT-16-1022, 2016) together with MCS and Convergent Science discusses the improvements to the Converge tool that has resulted in significant improvement in scaling. Currently, we are able to scale the code up to 4096 processors on Mira with about 70% scaling efficiency for a fixed mesh size. This was achieved due to the implementation of: (1) MPI I/O, (2) Improved Communication, (3) METIS load balancing scheme, (4) Development of a new chemistry load balancing scheme. The above changes are not only expected to benefit calculations on Mira but also help on computing clusters like Bebop and Blues. Storage requirements: 5 TB Thank You, The LCRC Accounts System