Primary Atomization (Near Nozzle Flows) Guidance on Experiments and Simulations to be Performed Sibendu Som: Argonne National Laboratory October 2 nd 2014

Experimental Objectives Focus on the near nozzle region within first 10 mm Concentrate on non-vaporizing experiments Provide boundary conditions for initializing the simulations for both Spray A and Spray B – Nozzle geometry – Rate of injection – Needle lift & off-axis motion – Injection pressure vs. time Provide data for validation for both Spray A and Spray B – Liquid mass distribution at nozzle exit and in the spray region – Droplet sizes – Qualitative physics to understand the spray processes – liquid penetration Assess the uncertainties for all of these parameters

Modeling Objectives Focus on the near nozzle region within first 10 mm Encourage high-fidelity simulations of fuel sprays to understand the primary atomization physics Capture the SOI and EOI physics for single and multi-hole injectors Capture the spray physics during the main injection process for both single and multi-hole injectors Study the capability of the different modeling approaches (Lagrangian-Eulerian, Eulerian-Eulerian) and CFD frameworks (RANS, LES, DNS) for the simulation of the primary atomization Assess which physical phenomena are important for including in models: Turbulence, Compressibility, …?

Target Injectors Spray A – Diesel nozzle, single hole, n-dodecane, non-cavitating – High resolution (1 mm) X-ray tomography of Nozzle 675 – Ultra High resolution (0.6 mm) tomography for 678, & 679 – Lift and wobble measured for all nozzles – The target injector will be Spray B – Diesel nozzle, 3-hole, n-dodecane –.stl files available for 196, 198, 199, 201 – Lift and wobble measured for all the injectors – The target injector will be 201 – Ultra High resolution (0.6  m) tomography completed and a CFD ready mesh is available

Conditions of Interest: Experiments Spray A and B operating conditions from Argonne: ( – Spray A: 675; Spray B: 201 – Priority 1: Pinj = 150 MPa; Priority 2: 100 MPa – Fuel temperature: Spray A K; Spray B – 338 K Spray A and Spray B conditions at Sandia and Univ. of Brighton: – Spray A: 675; Spray B: 201 – ?? Spray A and Spray B conditions at Chalmers??: – Spray A: 675; Spray B: 201 – ??

Conditions of Interest: Simulations Spray A and B operating conditions from Argonne: ( – Spray A: 675; Spray B: 201 – Priority 1: P inj = 150 MPa; Priority 2: P inj = 100 MPa – Fuel temperature: Spray A K; Spray B – 338 K Ambient gas temperature303 (K) Ambient gas pressure2.0 (MPa) Ambient gas density22.8 (kg/m3) Ambient gas N 2 (by volume)100%

Anticipated Experimental Results Microscopic measurements of the initial penetration and spreading angle as the needle opens Break up and mixing of the sprays at the end of injection at the microscopic level, possible dribble? USAXS droplet sizing and perhaps optically measured droplet size as well X-ray radiography of Spray A and Spray B nozzles and plumes of interest Ballistic imaging of near-nozzle region

For both Spray A and Spray B injectors: Mass flow rate at the nozzle exit from virtual ROI tool from CMT and measured nozzle coefficients (already available from ECN3) Fuel spray penetration vs. time from long-distance microscopy and diffused back-illumination Contour plots of projected liquid density at 0.1 ms and 0.5 ms from Argonne Transverse mass distribution (projected density across the spray) profiles averaged between 0.5 – 1.0 ms: o x = 0.1, 0.6, 2, 6, and 10 mm downstream to nozzle exit o Projection plane is 0°plane (i.e., plane containing fuel inlet, or projection along the z-axis with the injector in the theta = 0 position) Liquid volume fraction (LVF) across cross-section at x = 0.1, 0.6, 2, 6, 10 mm o the y-axis cut plane Transverse integrated mass (TIM) vs. axial 0.5 ms Mean droplet size (SMD) at x = 1, 4, 8 mm at 0.5 ms after SOI o Mean SMD at the above axial positions vs. axial position Data Needed from Experiments

Mass flow rate at the nozzle exit Fuel spray penetration vs. time (0.1% liquid mass fraction) Contour plots of projected density in the 0°plane at 0.1 and 0.5 ms after actual SOI Transverse mass distribution (projected density across the spray) in ug/mm x = 0.1, 0.6, 2, 6, and 10 mm downstream to nozzle exit: o between 0.5 – 1.0 ms after SOI, at intervals of 0.1 ms o Averaged profiles between ms at the above locations 2D contours of LVF at x = 0.1, 0.6, 2, 6, 10 mm at 0.5, 0.75, and 1.0 ms Transverse integrated mass profiles at 0.5 ms after SOI: o x = 0.1 mm, 0.6 mm, 2 mm, 6 mm, and 10 mm Mean droplet size (SMD) at x = 1, 4, 8 mm at 0.5 ms after SOI o Mean SMD at the above axial positions vs. axial position o Distributions of SMD vs. radial position at the above axial positions Dynamics: peak projected density and Full Width Half Maximum (FWHM) of distribution at x = 0.1, 2, 6 mm from nozzle for entire duration of the injection event (in intervals of 20 μs) Data Needed from Spray A Simulations Set-up conditions from Argonne

Spray B target injector (201): Compare results between different plumes for condition # 1 o Penetration vs. time o Transverse mass distribution at 0.1 mm, 2 mm, and 6 mm o Mean SMD at 1, 4 mm at 0.5 ms after SOI vs. axial position Data Needed from Spray B Simulations For plume # 3 which is measured at Argonne Contour plots of projected density in the 0°plane at 0.1 and 0.5 ms Transverse mass distribution (projected density across the spray) in ug/mm x = 0.1, 0.6, 2, 6, and 10 mm downstream to nozzle exit: o between 0.5 – 1.0 ms after SOI, at intervals of 0.1 ms o Averaged profiles between ms at the above locations 2D contours of LVF at x = 0.1, 0.6, 2, 6, 10 mm at 0.5, 0.75, 1.0 ms Transverse integrated mass profiles at 0.5 ms after SOI: o x = 0.1 mm, 0.6 mm, 2 mm, 6 mm, and 10 mm Mean droplet size (SMD) at x = 1, 4, 8 mm at 0.5 ms after SOI o Mean SMD at the above axial positions vs. axial position o Distributions of SMD vs. radial position at the above axial positions Set-up conditions from Argonne

Confirmed Participants and Volunteers Experiments Argonne, Sandia, Univ. of Brighton Confirm participation: Chalmers Simulations Argonne + Univ. of Perugia, ASU, Aachen, Sandia, CMT, GATECH Confirm participation: UMass, IFPEN, Coria Possible volunteers Experiments: ?? Simulations: ??