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OsSi is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Os4+ is bonded in a body-centered cubic geometry to eight equivalent Si4- atoms. All Os–Si bond lengths are 2.56 Å. Si4- is bonded in a body-centered cubic geometry to eight equivalent Os4+ atoms.
Dy(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Dy3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All Dy–Os bond lengths are 3.19 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Dy3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.48 Å.
Lu(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Lu3+ is bonded to eight equivalent Os+1.50- atoms to form distorted edge-sharing LuOs8 hexagonal bipyramids. All Lu–Os bond lengths are 3.16 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Lu3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.39 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.41 Å.
Gd(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Gd3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All Gd–Os bond lengths are 3.22 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Gd3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.52 Å.
OsSi crystallizes in the cubic P2_13 space group. The structure is three-dimensional. Os4+ is bonded in a 7-coordinate geometry to seven equivalent Si4- atoms. There are a spread of Os–Si bond distances ranging from 2.39–2.80 Å. Si4- is bonded in a 7-coordinate geometry to seven equivalent Os4+ atoms.
Th(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Th4+ is bonded in a 8-coordinate geometry to eight equivalent Os2- atoms. All Th–Os bond lengths are 3.24 Å. Os2- is bonded in a 4-coordinate geometry to four equivalent Th4+ and four equivalent Si atoms. All Os–Si bond lengths are 2.42 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os2- and one Si atom. The Si–Si bond length is 2.56 Å.
Yb(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Yb3+ is bonded to eight equivalent Os+1.50- atoms to form distorted edge-sharing YbOs8 hexagonal bipyramids. All Yb–Os bond lengths are 3.19 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Yb3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.52 Å.
La(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. La3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All La–Os bond lengths are 3.29 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent La3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.41 Å. Si is bonded in a 4-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.73 Å.
Y(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Y3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All Y–Os bond lengths are 3.19 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Y3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.49 Å.
Tm(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded to eight equivalent Os+1.50- atoms to form distorted edge-sharing TmOs8 hexagonal bipyramids. All Tm–Os bond lengths are 3.17 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Tm3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.39 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.44 Å.
Nd(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Nd3+ is bonded in a 8-coordinate geometry to eight equivalent Os+1.50- atoms. All Nd–Os bond lengths are 3.25 Å. Os+1.50- is bonded in a 4-coordinate geometry to four equivalent Nd3+ and four equivalent Si atoms. All Os–Si bond lengths are 2.41 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os+1.50- and one Si atom. The Si–Si bond length is 2.62 Å.
U(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. U4+ is bonded in a 8-coordinate geometry to eight equivalent Os2- atoms. All U–Os bond lengths are 3.17 Å. Os2- is bonded in a 4-coordinate geometry to four equivalent U4+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os2- and one Si atom. The Si–Si bond length is 2.37 Å.
Np(OsSi)2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Np4+ is bonded in a 8-coordinate geometry to eight equivalent Os2- atoms. All Np–Os bond lengths are 3.17 Å. Os2- is bonded in a 4-coordinate geometry to four equivalent Np4+ and four equivalent Si atoms. All Os–Si bond lengths are 2.40 Å. Si is bonded in a 5-coordinate geometry to four equivalent Os2- and one Si atom. The Si–Si bond length is 2.35 Å.
This paper presents a three-dimensional (3-D) computational fluid dynamics (CFD) study of a motored cooperative fuel research (CFR) engine at research octane number (RON) relevant condition. The boundary conditions for 3-D simulations were generated with a one-dimensional GT-Power model. For the first time in literature, a carburetor was added to a virtual CFR engine model with 3-D CFD. Therefore, the proposed setup can simulate the fuel and thermal stratifications inside the engine cylinder with realistic detail. The transient simulations in this work were performed within the Reynolds-averaged Navier-Stokes (RANS) framework with a Realizable k-ε turbulence model. Major conclusions from the present work are: (1) The in-cylinder flow of the CFR engine is swirl-dominated due to the existence of the intake valve shroud. (2) There is a significant amount of liquid droplets entering the cylinder during the intake stroke. The maximum instantaneous amount of liquid for 50% PRF 87 (containing 87% iso-octane and 13% n-heptane (v/v)) and 50% ethanol mixture is indicated to be around 26% of total injected fuel mass. (3) The heat of vaporization (HoV) of the fuel is responsible for creating both temperature and charge stratification inside the cylinder.