6 VERIFICATION AND ENHANCEMENT OF PREDICTIVE COMPUTATIONAL MATERIAL MODELS FOR SOLID-LIQUID MIXTURES BASED ON EXPERIMENTS CONDUCTED ON EARTH IS CHALLENGING BECAUSE OF THE DETRIMENTAL GRAVITATIONAL EFFECTS ON SOLID PARTICLES AND LIQUID MIXTURES E.G. BUOYANCY-INDUCED CONVECTION AND PARTICLE SEDIMENTATION. MICROGRAVITY ENVIRONMENT FOR NASA-PSI 'COARSENING IN SOLID-LIQUID MIXTURES EXPERIMENTS' PROVIDES DATA WITHOUT THE DETRIMENTAL GRAVITATIONAL EFFECTS THAT CAN BE USED FOR VERIFICATION AND ENHANCEMENT OF PREDICTIVE MODELS. IN RETURN, THE VERIFIED/ENHANCED MODEL CAN BE USED TO PREDICT COARSENING IN SOLID-LIQUID MIXTURES THAT IDEALLY ELIMINATES THE NEED TO CONDUCT SIMILAR EXPERIMENTS FOR OTHER MATERIALS AND ALSO EXPERIMENTS FOR OTHER PHENOMENA INVOLVED WITH SOLID-LIQUID COEXISTING. THE MENTIONED PREDICTIVE CAPABILITY IS ONLY POSSIBLE IF THE COMPUTATIONAL MODEL IS NOT DERIVED PHENOMENOLOGICALLY FOR THE SPECIFIC APPLICATION AND MATERIAL PHASE-FIELD CRYSTALS (PFC) ARE A CLASS OF SUCH PREDICTIVE COMPUTATIONAL MODELS. THEREFORE, THE OBJECTIVES OF THIS PROPOSAL ARE: 1) THE DEVELOPMENT OF A QUANTITATIVE MULTI-TIME AND LENGTH-SCALE COMPUTATIONAL MODELING FRAMEWORK AND TOOL AROUND PFC TO PREDICT COARSENING IN PB-SN SOLID-LIQUID MIXTURES. CHALLENGES FOR THIS OBJECTIVE ARE QUANTIFYING THE PFC MODEL AND DEVELOPING AN EFFICIENT COMPUTATIONAL TOOL FOR THREE-DIMENSIONAL (3D) SIMULATIONS. 2) DATA MINING OF NASA-PSI CSLM, CSLM-2, CSLM-2R, AND CSLM-3 EXPERIMENTS AND USING THEM IN SERIES OF SIMULATIONS IN THE DEVELOPED COMPUTATIONAL TOOL FOR ENHANCEMENT AND VERIFICATION OF THE PROPOSED MODELING FRAMEWORK. THE CHALLENGE FOR THIS OBJECTIVE IS THE HUGE NUMBER OF 3D SIMULATIONS THAT REQUIRE SIGNIFICANT AMOUNT OF COMPUTER POWER. 3) QUANTIFYING THE DEVELOPED MODEL AND TOOL TO AL-CU SOLID-LIQUID MIXTURES TO SHOW THE POTENTIAL BENEFITS OF THE PROPOSED RESEARCH. THE CHALLENGE FOR THIS OBJECTIVE IS ONLY THE QUANTIFICATION PROCESS OF THE MODEL. PFC IS A UNIQUE COMPUTATIONAL MODEL WITH THE CAPABILITY OF SIMULATING SOLID-LIQUID PROCESSES ON DIFFUSIVE TIME SCALES WITH ATOMISTIC RESOLUTIONS, WHICH ARE THE REQUIREMENTS FOR QUANTITATIVE SIMULATION OF COARSENING IN SOLID-LIQUID MIXTURES. PFC IS DIRECTLY DEVELOPED FROM DYNAMICAL DENSITY FUNCTIONAL THEORY (DDFT) THUS, IT INHERITS THE SAME PREDICTIVE CAPABILITY AS DDFT. HOWEVER, THE LENGTHSCALE OF PFC NEEDS TO BE EXTENDED TO MICROSCALE WHICH IS THE TYPICAL SIZE OF THE SOLID PARTICLES IN CSLM EXPERIMENTS. THE LENGTH SCALE EXTENSION OF PFC WILL BE ACHIEVED BY USING THE AMPLITUDE EQUATIONS OF PFC (EXTENDED LENGTH-SCALE PFC, EL-PFC) AND DEVELOPING A HIGHLY-PARALLEL SEMI-IMPLICIT SPECTRAL AND OPERATOR SPLITTING NUMERICAL ALGORITHM. MOLECULAR DYNAMICS (MD) SIMULATIONS WILL BE USED TO PROVIDE THE NECESSARY MATERIAL PROPERTIES (E.G. LIQUID STRUCTURE FACTOR AND SOLID/LIQUID ELASTIC CONSTANTS AT EUTECTIC TEMPERATURE) TO QUANTIFY PFC/EL-PFC MODEL FOR PB-SN AND AL-CU. THE EXPLAINED MD, PFC, AND EL-PFC MODELING FRAMEWORK AND NUMERICAL ALGORITHM RESULT IN A QUANTITATIVE COMPUTATIONAL TOOL THAT CAN PREDICT COARSENING IN SOLID-LIQUID MIXTURES. THE IMAGES OF COARSENING SN PARTICLES IN PB-SN LIQUID MIXTURES WILL BE EXTRACTED FROM CSLM EXPERIMENTS. THE IMAGES AT THE INITIAL TIME WILL BE USED AS THE INITIAL MICROSTRUCTURE AT THE DEVELOPED COMPUTATIONAL TOOL AND LONGER-TIME MICROSTRUCTURES WILL BE PREDICTED VIA SIMULATIONS FOR VERIFICATION/ENHANCEMENT OF THE DEVELOPED MODEL. THE PROPOSED COMPUTATIONAL TOOL WILL ESTABLISH A VIRTUAL LABORATORY THAT CAN BE USED TO STUDY INFLUENCE OF VOLUME FRACTION, GRAIN BOUNDARIES AND ORIENTATIONS, VACANCIES, DISLOCATIONS, AND IMPURITIES ON COARSENING RATE AND MECHANISM. WE WILL USE THIS VIRTUAL LABORATORY TO STUDY COARSENING IN AL-CU LIQUID MIXTURES TO DEMONSTRATE THE POTENTIAL APPLICATION OF THE PROPOSED RESEARCH. THE RESULTS OF THIS RESEARCH WILL BE DISSEMINATED TO THE PUBLIC IN FORMS OF PEER REVIEWED ARTICLES, SCIENTIFIC REPORTS, A PROJECT-SPECIFIC WEBSITE, AND DATA UPLOADED TO NASA-PSI WEBSITE. Funding Only Action ($4k) 6/22/20 Not listed VERIFICATION AND ENHANCEMENT OF PREDICTIVE COMPUTATIONAL MATERIAL MODELS FOR SOLID-LIQUID MIXTURES BASED ON EXPERIMENTS CONDUCTED ON EARTH IS CHALLENGING BECAUSE OF THE DETRIMENTAL GRAVITATIONAL EFFECTS ON SOLID PARTICLES AND LIQUID MIXTURES E.G. BUOYANCY-INDUCED CONVECTION AND PARTICLE SEDIMENTATION. MICROGRAVITY ENVIRONMENT FOR NASA-PSI 'COARSENING IN SOLID-LIQUID MIXTURES EXPERIMENTS' PROVIDES DATA WITHOUT THE DETRIMENTAL GRAVITATIONAL EFFECTS THAT CAN BE USED FOR VERIFICATION AND ENHANCEMENT OF PREDICTIVE MODELS. IN RETURN THE VERIFIED/ENHANCED MODEL CAN BE USED TO PREDICT COARSENING IN SOLID-LIQUID MIXTURES THAT IDEALLY ELIMINATES THE NEED TO CONDUCT SIMILAR EXPERIMENTS FOR OTHER MATERIALS AND ALSO EXPERIMENTS FOR OTHER PHENOMENA INVOLVED WITH SOLID-LIQUID COEXISTING.THE MENTIONED PREDICTIVE CAPABILITY IS ONLY POSSIBLE IF THE COMPUTATIONAL MODEL IS NOT DERIVED PHENOMENOLOGICALLY FOR THE SPECIFIC APPLICATION AND MATERIAL PHASE-FIELD CRYSTALS (PFC) ARE A CLASS OF SUCH PREDICTIVE COMPUTATIONAL MODELS. THEREFORE THE OBJECTIVES OF THIS PROPOSAL ARE:1) THE DEVELOPMENT OF A QUANTITATIVE MULTI-TIME AND LENGTH-SCALE COMPUTATIONAL MODELING FRAMEWORK AND TOOL AROUND PFC TO PREDICT COARSENING IN PB-SN SOLID-LIQUID MIXTURES. CHALLENGES FOR THIS OBJECTIVE ARE QUANTIFYING THE PFC MODEL AND DEVELOPING AN EFFICIENT COMPUTATIONAL TOOL FOR THREE-DIMENSIONAL (3D) SIMULATIONS.2) DATA MINING OF NASA-PSI CSLM CSLM-2 CSLM-2R AND CSLM-3 EXPERIMENTS AND USING THEM IN SERIES OF SIMULATIONS IN THE DEVELOPED COMPUTATIONAL TOOL FOR ENHANCEMENT AND VERIFICATION OF THE PROPOSED MODELING FRAMEWORK. THE CHALLENGE FOR THIS OBJECTIVE IS THE HUGE NUMBER OF 3D SIMULATIONS THAT REQUIRE SIGNIFICANT AMOUNT OF COMPUTER POWER.3) QUANTIFYING THE DEVELOPED MODEL AND TOOL TO AL-CU SOLID-LIQUID MIXTURES TO SHOW THE POTENTIAL BENEFITS OF THE PROPOSED RESEARCH. THE CHALLENGE FOR THIS OBJECTIVE IS ONLY THE QUANTIFICATION PROCESS OF THE MODEL.PFC IS A UNIQUE COMPUTATIONAL MODEL WITH THE CAPABILITY OF SIMULATING SOLID-LIQUID PROCESSES ON DIFFUSIVE TIME SCALES WITH ATOMISTIC RESOLUTIONS WHICH ARE THE REQUIREMENTS FOR QUANTITATIVE SIMULATION OF COARSENING IN SOLID-LIQUID MIXTURES. PFC IS DIRECTLY DEVELOPED FROM DYNAMICAL DENSITY FUNCTIONAL THEORY (DDFT) THUS IT INHERITS THE SAME PREDICTIVE CAPABILITY AS DDFT. HOWEVER THE LENGTHSCALE OF PFC NEEDS TO BE EXTENDED TO MICROSCALE WHICH IS THE TYPICAL SIZE OF THE SOLID PARTICLES IN CSLM EXPERIMENTS. THE LENGTH SCALE EXTENSION OF PFC WILL BE ACHIEVED BY USING THE AMPLITUDE EQUATIONS OF PFC (EXTENDED LENGTH-SCALE PFC EL-PFC) AND DEVELOPING A HIGHLY-PARALLEL SEMI-IMPLICIT SPECTRAL AND OPERATOR SPLITTING NUMERICAL ALGORITHM. MOLECULAR DYNAMICS (MD) SIMULATIONS WILL BE USED TO PROVIDE THE NECESSARY MATERIAL PROPERTIES (E.G. LIQUID STRUCTURE FACTOR AND SOLID/LIQUID ELASTIC CONSTANTS AT EUTECTIC TEMPERATURE) TO QUANTIFY PFC/EL-PFC MODEL FOR PB-SN AND AL-CU. THE EXPLAINED MD PFC AND EL-PFC MODELING FRAMEWORK AND NUMERICAL ALGORITHM RESULT IN A QUANTITATIVE COMPUTATIONAL TOOL THAT CAN PREDICT COARSENING IN SOLID-LIQUID MIXTURES. THE IMAGES OF COARSENING SN PARTICLES IN PB-SN LIQUID MIXTURES WILL BE EXTRACTED FROM CSLM EXPERIMENTS. THE IMAGES AT THE INITIAL TIME WILL BE USED AS THE INITIAL MICROSTRUCTURE AT THE DEVELOPED COMPUTATIONAL TOOL AND LONGER-TIME MICROSTRUCTURES WILL BE PREDICTED VIA SIMULATIONS FOR VERIFICATION/ENHANCEMENT OF THE DEVELOPED MODEL. THE PROPOSED COMPUTATIONAL TOOL WILL ESTABLISH A VIRTUAL LABORATORY THAT CAN BE USED TO STUDY INFLUENCE OF VOLUME FRACTION GRAIN BOUNDARIES AND ORIENTATIONS VACANCIES DISLOCATIONS AND IMPURITIES ON COARSENING RATE AND MECHANISM. WE WILL USE THIS VIRTUAL LABORATORY TO STUDY COARSENING IN AL-CU LIQUID MIXTURES TO DEMONSTRATE THE POTENTIAL APPLICATION OF THE PROPOSED RESEARCH. THE RESULTS OF THIS RESEARCH WILL BE DISSEMINATED TO THE PUBLIC IN FORMS OF PEER REVIEWED ARTICLES SCIENTIFIC REPORTS A PROJECT-SPECIFIC WEBSITE AND DATA UPLOADED TO NASA-PSI WEBSITE. ($4k) 6/22/20 5 VERIFICATION AND ENHANCEMENT OF PREDICTIVE COMPUTATIONAL MATERIAL MODELS FOR SOLID-LIQUID MIXTURES BASED ON EXPERIMENTS CONDUCTED ON EARTH IS CHALLENGING BECAUSE OF THE DETRIMENTAL GRAVITATIONAL EFFECTS ON SOLID PARTICLES AND LIQUID MIXTURES; E.G. BUOYANCY-INDUCED CONVECTION AND PARTICLE SEDIMENTATION. MICROGRAVITY ENVIRONMENT FOR NASA-PSI 'COARSENING IN SOLID-LIQUID MIXTURES EXPERIMENTS' PROVIDES DATA WITHOUT THE DETRIMENTAL GRAVITATIONAL EFFECTS THAT CAN BE USED FOR VERIFICATION AND ENHANCEMENT OF PREDICTIVE MODELS. IN RETURN, THE VERIFIED/ENHANCED MODEL CAN BE USED TO PREDICT COARSENING IN SOLID-LIQUID MIXTURES THAT IDEALLY ELIMINATES THE NEED TO CONDUCT SIMILAR EXPERIMENTS FOR OTHER MATERIALS AND ALSO EXPERIMENTS FOR OTHER PHENOMENA INVOLVED WITH SOLID-LIQUID COEXISTING. THE MENTIONED PREDICTIVE CAPABILITY IS ONLY POSSIBLE IF THE COMPUTATIONAL MODEL IS NOT DERIVED PHENOMENOLOGICALLY FOR THE SPECIFIC APPLICATION AND MATERIAL; PHASE-FIELD CRYSTALS (PFC) ARE A CLASS OF SUCH PREDICTIVE COMPUTATIONAL MODELS. THEREFORE, THE OBJECTIVES OF THIS PROPOSAL ARE: 1) THE DEVELOPMENT OF A QUANTITATIVE MULTI-TIME AND LENGTH-SCALE COMPUTATIONAL MODELING FRAMEWORK AND TOOL AROUND PFC TO PREDICT COARSENING IN PB-SN SOLID-LIQUID MIXTURES. CHALLENGES FOR THIS OBJECTIVE ARE QUANTIFYING THE PFC MODEL AND DEVELOPING AN EFFICIENT COMPUTATIONAL TOOL FOR THREE-DIMENSIONAL (3D) SIMULATIONS. 2) DATA MINING OF NASA-PSI CSLM, CSLM-2, CSLM-2R, AND CSLM-3 EXPERIMENTS AND USING THEM IN SERIES OF SIMULATIONS IN THE DEVELOPED COMPUTATIONAL TOOL FOR ENHANCEMENT AND VERIFICATION OF THE PROPOSED MODELING FRAMEWORK. THE CHALLENGE FOR THIS OBJECTIVE IS THE HUGE NUMBER OF 3D SIMULATIONS THAT REQUIRE SIGNIFICANT AMOUNT OF COMPUTER POWER. 3) QUANTIFYING THE DEVELOPED MODEL AND TOOL TO AL-CU SOLID-LIQUID MIXTURES TO SHOW THE POTENTIAL BENEFITS OF THE PROPOSED RESEARCH. THE CHALLENGE FOR THIS OBJECTIVE IS ONLY THE QUANTIFICATION PROCESS OF THE MODEL. PFC IS A UNIQUE COMPUTATIONAL MODEL WITH THE CAPABILITY OF SIMULATING SOLID-LIQUID PROCESSES ON DIFFUSIVE TIME SCALES WITH ATOMISTIC RESOLUTIONS, WHICH ARE THE REQUIREMENTS FOR QUANTITATIVE SIMULATION OF COARSENING IN SOLID-LIQUID MIXTURES. PFC IS DIRECTLY DEVELOPED FROM DYNAMICAL DENSITY FUNCTIONAL THEORY (DDFT); THUS, IT INHERITS THE SAME PREDICTIVE CAPABILITY AS DDFT. HOWEVER, THE LENGTHSCALE OF PFC NEEDS TO BE EXTENDED TO MICROSCALE WHICH IS THE TYPICAL SIZE OF THE SOLID PARTICLES IN CSLM EXPERIMENTS. THE LENGTH SCALE EXTENSION OF PFC WILL BE ACHIEVED BY USING THE AMPLITUDE EQUATIONS OF PFC (EXTENDED LENGTH-SCALE PFC, EL-PFC) AND DEVELOPING A HIGHLY-PARALLEL SEMI-IMPLICIT SPECTRAL AND OPERATOR SPLITTING NUMERICAL ALGORITHM. MOLECULAR DYNAMICS (MD) SIMULATIONS WILL BE USED TO PROVIDE THE NECESSARY MATERIAL PROPERTIES (E.G. LIQUID STRUCTURE FACTOR AND SOLID/LIQUID ELASTIC CONSTANTS AT EUTECTIC TEMPERATURE) TO QUANTIFY PFC/EL-PFC MODEL FOR PB-SN AND AL-CU. THE EXPLAINED MD, PFC, AND EL-PFC MODELING FRAMEWORK AND NUMERICAL ALGORITHM RESULT IN A QUANTITATIVE COMPUTATIONAL TOOL THAT CAN PREDICT COARSENING IN SOLID-LIQUID MIXTURES. THE IMAGES OF COARSENING SN PARTICLES IN PB-SN LIQUID MIXTURES WILL BE EXTRACTED FROM CSLM EXPERIMENTS. THE IMAGES AT THE INITIAL TIME WILL BE USED AS THE INITIAL MICROSTRUCTURE AT THE DEVELOPED COMPUTATIONAL TOOL AND LONGER-TIME MICROSTRUCTURES WILL BE PREDICTED VIA SIMULATIONS FOR VERIFICATION/ENHANCEMENT OF THE DEVELOPED MODEL. THE PROPOSED COMPUTATIONAL TOOL WILL ESTABLISH A VIRTUAL LABORATORY THAT CAN BE USED TO STUDY INFLUENCE OF VOLUME FRACTION, GRAIN BOUNDARIES AND ORIENTATIONS, VACANCIES, DISLOCATIONS, AND IMPURITIES ON COARSENING RATE AND MECHANISM. WE WILL USE THIS VIRTUAL LABORATORY TO STUDY COARSENING IN AL-CU LIQUID MIXTURES TO DEMONSTRATE THE POTENTIAL APPLICATION OF THE PROPOSED RESEARCH. THE RESULTS OF THIS RESEARCH WILL BE DISSEMINATED TO THE PUBLIC IN FORMS OF PEER REVIEWED ARTICLES, SCIENTIFIC REPORTS, A PROJECT-SPECIFIC WEBSITE, AND DATA UPLOADED TO NASA-PSI WEBSITE. Other Administrative Action $0 1/28/19 Not listed VERIFICATION AND ENHANCEMENT OF PREDICTIVE COMPUTATIONAL MATERIAL MODELS FOR SOLID-LIQUID MIXTURES BASED ON EXPERIMENTS CONDUCTED ON EARTH IS CHALLENGING BECAUSE OF THE DETRIMENTAL GRAVITATIONAL EFFECTS ON SOLID PARTICLES AND LIQUID MIXTURES; E.G. BUOYANCY-INDUCED CONVECTION AND PARTICLE SEDIMENTATION. MICROGRAVITY ENVIRONMENT FOR NASA-PSI 'COARSENING IN SOLID-LIQUID MIXTURES EXPERIMENTS' PROVIDES DATA WITHOUT THE DETRIMENTAL GRAVITATIONAL EFFECTS THAT CAN BE USED FOR VERIFICATION AND ENHANCEMENT OF PREDICTIVE MODELS. IN RETURN THE VERIFIED/ENHANCED MODEL CAN BE USED TO PREDICT COARSENING IN SOLID-LIQUID MIXTURES THAT IDEALLY ELIMINATES THE NEED TO CONDUCT SIMILAR EXPERIMENTS FOR OTHER MATERIALS AND ALSO EXPERIMENTS FOR OTHER PHENOMENA INVOLVED WITH SOLID-LIQUID COEXISTING.THE MENTIONED PREDICTIVE CAPABILITY IS ONLY POSSIBLE IF THE COMPUTATIONAL MODEL IS NOT DERIVED PHENOMENOLOGICALLY FOR THE SPECIFIC APPLICATION AND MATERIAL; PHASE-FIELD CRYSTALS (PFC) ARE A CLASS OF SUCH PREDICTIVE COMPUTATIONAL MODELS. THEREFORE THE OBJECTIVES OF THIS PROPOSAL ARE:1) THE DEVELOPMENT OF A QUANTITATIVE MULTI-TIME AND LENGTH-SCALE COMPUTATIONAL MODELING FRAMEWORK AND TOOL AROUND PFC TO PREDICT COARSENING IN PB-SN SOLID-LIQUID MIXTURES. CHALLENGES FOR THIS OBJECTIVE ARE QUANTIFYING THE PFC MODEL AND DEVELOPING AN EFFICIENT COMPUTATIONAL TOOL FOR THREE-DIMENSIONAL (3D) SIMULATIONS.2) DATA MINING OF NASA-PSI CSLM CSLM-2 CSLM-2R AND CSLM-3 EXPERIMENTS AND USING THEM IN SERIES OF SIMULATIONS IN THE DEVELOPED COMPUTATIONAL TOOL FOR ENHANCEMENT AND VERIFICATION OF THE PROPOSED MODELING FRAMEWORK. THE CHALLENGE FOR THIS OBJECTIVE IS THE HUGE NUMBER OF 3D SIMULATIONS THAT REQUIRE SIGNIFICANT AMOUNT OF COMPUTER POWER.3) QUANTIFYING THE DEVELOPED MODEL AND TOOL TO AL-CU SOLID-LIQUID MIXTURES TO SHOW THE POTENTIAL BENEFITS OF THE PROPOSED RESEARCH. THE CHALLENGE FOR THIS OBJECTIVE IS ONLY THE QUANTIFICATION PROCESS OF THE MODEL.PFC IS A UNIQUE COMPUTATIONAL MODEL WITH THE CAPABILITY OF SIMULATING SOLID-LIQUID PROCESSES ON DIFFUSIVE TIME SCALES WITH ATOMISTIC RESOLUTIONS WHICH ARE THE REQUIREMENTS FOR QUANTITATIVE SIMULATION OF COARSENING IN SOLID-LIQUID MIXTURES. PFC IS DIRECTLY DEVELOPED FROM DYNAMICAL DENSITY FUNCTIONAL THEORY (DDFT); THUS IT INHERITS THE SAME PREDICTIVE CAPABILITY AS DDFT. HOWEVER THE LENGTHSCALE OF PFC NEEDS TO BE EXTENDED TO MICROSCALE WHICH IS THE TYPICAL SIZE OF THE SOLID PARTICLES IN CSLM EXPERIMENTS. THE LENGTH SCALE EXTENSION OF PFC WILL BE ACHIEVED BY USING THE AMPLITUDE EQUATIONS OF PFC (EXTENDED LENGTH-SCALE PFC EL-PFC) AND DEVELOPING A HIGHLY-PARALLEL SEMI-IMPLICIT SPECTRAL AND OPERATOR SPLITTING NUMERICAL ALGORITHM. MOLECULAR DYNAMICS (MD) SIMULATIONS WILL BE USED TO PROVIDE THE NECESSARY MATERIAL PROPERTIES (E.G. LIQUID STRUCTURE FACTOR AND SOLID/LIQUID ELASTIC CONSTANTS AT EUTECTIC TEMPERATURE) TO QUANTIFY PFC/EL-PFC MODEL FOR PB-SN AND AL-CU. THE EXPLAINED MD PFC AND EL-PFC MODELING FRAMEWORK AND NUMERICAL ALGORITHM RESULT IN A QUANTITATIVE COMPUTATIONAL TOOL THAT CAN PREDICT COARSENING IN SOLID-LIQUID MIXTURES. THE IMAGES OF COARSENING SN PARTICLES IN PB-SN LIQUID MIXTURES WILL BE EXTRACTED FROM CSLM EXPERIMENTS. THE IMAGES AT THE INITIAL TIME WILL BE USED AS THE INITIAL MICROSTRUCTURE AT THE DEVELOPED COMPUTATIONAL TOOL AND LONGER-TIME MICROSTRUCTURES WILL BE PREDICTED VIA SIMULATIONS FOR VERIFICATION/ENHANCEMENT OF THE DEVELOPED MODEL. THE PROPOSED COMPUTATIONAL TOOL WILL ESTABLISH A VIRTUAL LABORATORY THAT CAN BE USED TO STUDY INFLUENCE OF VOLUME FRACTION GRAIN BOUNDARIES AND ORIENTATIONS VACANCIES DISLOCATIONS AND IMPURITIES ON COARSENING RATE AND MECHANISM. WE WILL USE THIS VIRTUAL LABORATORY TO STUDY COARSENING IN AL-CU LIQUID MIXTURES TO DEMONSTRATE THE POTENTIAL APPLICATION OF THE PROPOSED RESEARCH. THE RESULTS OF THIS RESEARCH WILL BE DISSEMINATED TO THE PUBLIC IN FORMS OF PEER REVIEWED ARTICLES SCIENTIFIC REPORTS A PROJECT-SPECIFIC WEBSITE AND DATA UPLOADED TO NASA-PSI WEBSITE. $0 1/28/19 Not listed VERIFICATION AND ENHANCEMENT OF PREDICTIVE COMPUTATIONAL MATERIAL MODELS FOR SOLID-LIQUID MIXTURES BASED ON EXPERIMENTS CONDUCTED ON EARTH IS CHALLENGING BECAUSE OF THE DETRIMENTAL GRAVITATIONAL EFFECTS ON SOLID PARTICLES AND LIQUID MIXTURES; E.G. BUOYANCY-INDUCED CONVECTION AND PARTICLE SEDIMENTATION. MICROGRAVITY ENVIRONMENT FOR NASA-PSI 'COARSENING IN SOLID-LIQUID MIXTURES EXPERIMENTS' PROVIDES DATA WITHOUT THE DETRIMENTAL GRAVITATIONAL EFFECTS THAT CAN BE USED FOR VERIFICATION AND ENHANCEMENT OF PREDICTIVE MODELS. IN RETURN THE VERIFIED/ENHANCED MODEL CAN BE USED TO PREDICT COARSENING IN SOLID-LIQUID MIXTURES THAT IDEALLY ELIMINATES THE NEED TO CONDUCT SIMILAR EXPERIMENTS FOR OTHER MATERIALS AND ALSO EXPERIMENTS FOR OTHER PHENOMENA INVOLVED WITH SOLID-LIQUID COEXISTING.THE MENTIONED PREDICTIVE CAPABILITY IS ONLY POSSIBLE IF THE COMPUTATIONAL MODEL IS NOT DERIVED PHENOMENOLOGICALLY FOR THE SPECIFIC APPLICATION AND MATERIAL; PHASE-FIELD CRYSTALS (PFC) ARE A CLASS OF SUCH PREDICTIVE COMPUTATIONAL MODELS. THEREFORE THE OBJECTIVES OF THIS PROPOSAL ARE:1) THE DEVELOPMENT OF A QUANTITATIVE MULTI-TIME AND LENGTH-SCALE COMPUTATIONAL MODELING FRAMEWORK AND TOOL AROUND PFC TO PREDICT COARSENING IN PB-SN SOLID-LIQUID MIXTURES. CHALLENGES FOR THIS OBJECTIVE ARE QUANTIFYING THE PFC MODEL AND DEVELOPING AN EFFICIENT COMPUTATIONAL TOOL FOR THREE-DIMENSIONAL (3D) SIMULATIONS.2) DATA MINING OF NASA-PSI CSLM CSLM-2 CSLM-2R AND CSLM-3 EXPERIMENTS AND USING THEM IN SERIES OF SIMULATIONS IN THE DEVELOPED COMPUTATIONAL TOOL FOR ENHANCEMENT AND VERIFICATION OF THE PROPOSED MODELING FRAMEWORK. THE CHALLENGE FOR THIS OBJECTIVE IS THE HUGE NUMBER OF 3D SIMULATIONS THAT REQUIRE SIGNIFICANT AMOUNT OF COMPUTER POWER.3) QUANTIFYING THE DEVELOPED MODEL AND TOOL TO AL-CU SOLID-LIQUID MIXTURES TO SHOW THE POTENTIAL BENEFITS OF THE PROPOSED RESEARCH. THE CHALLENGE FOR THIS OBJECTIVE IS ONLY THE QUANTIFICATION PROCESS OF THE MODEL.PFC IS A UNIQUE COMPUTATIONAL MODEL WITH THE CAPABILITY OF SIMULATING SOLID-LIQUID PROCESSES ON DIFFUSIVE TIME SCALES WITH ATOMISTIC RESOLUTIONS WHICH ARE THE REQUIREMENTS FOR QUANTITATIVE SIMULATION OF COARSENING IN SOLID-LIQUID MIXTURES. PFC IS DIRECTLY DEVELOPED FROM DYNAMICAL DENSITY FUNCTIONAL THEORY (DDFT); THUS IT INHERITS THE SAME PREDICTIVE CAPABILITY AS DDFT. HOWEVER THE LENGTHSCALE OF PFC NEEDS TO BE EXTENDED TO MICROSCALE WHICH IS THE TYPICAL SIZE OF THE SOLID PARTICLES IN CSLM EXPERIMENTS. THE LENGTH SCALE EXTENSION OF PFC WILL BE ACHIEVED BY USING THE AMPLITUDE EQUATIONS OF PFC (EXTENDED LENGTH-SCALE PFC EL-PFC) AND DEVELOPING A HIGHLY-PARALLEL SEMI-IMPLICIT SPECTRAL AND OPERATOR SPLITTING NUMERICAL ALGORITHM. MOLECULAR DYNAMICS (MD) SIMULATIONS WILL BE USED TO PROVIDE THE NECESSARY MATERIAL PROPERTIES (E.G. LIQUID STRUCTURE FACTOR AND SOLID/LIQUID ELASTIC CONSTANTS AT EUTECTIC TEMPERATURE) TO QUANTIFY PFC/EL-PFC MODEL FOR PB-SN AND AL-CU. THE EXPLAINED MD PFC AND EL-PFC MODELING FRAMEWORK AND NUMERICAL ALGORITHM RESULT IN A QUANTITATIVE COMPUTATIONAL TOOL THAT CAN PREDICT COARSENING IN SOLID-LIQUID MIXTURES. THE IMAGES OF COARSENING SN PARTICLES IN PB-SN LIQUID MIXTURES WILL BE EXTRACTED FROM CSLM EXPERIMENTS. THE IMAGES AT THE INITIAL TIME WILL BE USED AS THE INITIAL MICROSTRUCTURE AT THE DEVELOPED COMPUTATIONAL TOOL AND LONGER-TIME MICROSTRUCTURES WILL BE PREDICTED VIA SIMULATIONS FOR VERIFICATION/ENHANCEMENT OF THE DEVELOPED MODEL. THE PROPOSED COMPUTATIONAL TOOL WILL ESTABLISH A VIRTUAL LABORATORY THAT CAN BE USED TO STUDY INFLUENCE OF VOLUME FRACTION GRAIN BOUNDARIES AND ORIENTATIONS VACANCIES DISLOCATIONS AND IMPURITIES ON COARSENING RATE AND MECHANISM. WE WILL USE THIS VIRTUAL LABORATORY TO STUDY COARSENING IN AL-CU LIQUID MIXTURES TO DEMONSTRATE THE POTENTIAL APPLICATION OF THE PROPOSED RESEARCH. THE RESULTS OF THIS RESEARCH WILL BE DISSEMINATED TO THE PUBLIC IN FORMS OF PEER REVIEWED ARTICLES SCIENTIFIC REPORTS A PROJECT-SPECIFIC WEBSITE AND DATA UPLOADED TO NASA-PSI WEBSITE. $59.0k 3/15/18