Definition,Expansion and Screening of Architectures for Planetary Exploration Class Nuclear Electric Propulsion and Power Systems By Bryan K.Smith Submitted to the System Design and Management Program in Partial Fulfillment of the Requirements for the Degree of Master of Science in Engineering and Management. ABSTRACT This work applies a structured approach to architectural definition,expansion and screening of Nuclear Electric Propulsion and Power concepts capable of achieving planetary exploration class science missions.Problem definition is first achieved through the completion of domain identification,functional decompositions,determining interdependencies and mapping the functions to the general design form.The thesis then adapts an architectural framework that allows the introduction of a spectrum of architectural influences and further defines top-level goals and objectives.Concepts are described by functional elements and the associated concept combination matrices are generated by first level function.In order to resolve complexity,this analysis distinguishes between what are pivotal elements of the architecture and what are only design attributes.The most influential architectural concept elements form the basis for inclusion in the concept combination matrices.Reductions in concepts are first achieved through a filtering of the individual subsystem element combination matrices using the results of the architectural framework analysis and defined objectives and goals.Concept screening is then accomplished through the development of screening criteria and application of the criteria to a relative concept scoring matrix that rates the remaining system level concepts.The highest scoring concept combinations are identified for further quantitative study and potential technology investment.Applicability of the results is discussed for the formulation of a multidisciplinary design problem that can be further investigated when detailed subsystem models are developed. Thesis Supervisor:Olivier L.de Weck Title:Assistant Professor of Aeronautics Astronautics and Engineering Systems 3Definition, Expansion and Screening of Architectures for Planetary Exploration Class Nuclear Electric Propulsion and Power Systems By Bryan K. Smith Submitted to the System Design and Management Program in Partial Fulfillment of the Requirements for the Degree of Master of Science in Engineering and Management. ABSTRACT This work applies a structured approach to architectural definition, expansion and screening of Nuclear Electric Propulsion and Power concepts capable of achieving planetary exploration class science missions. Problem definition is first achieved through the completion of domain identification, functional decompositions, determining interdependencies and mapping the functions to the general design form. The thesis then adapts an architectural framework that allows the introduction of a spectrum of architectural influences and further defines top-level goals and objectives. Concepts are described by functional elements and the associated concept combination matrices are generated by first level function. In order to resolve complexity, this analysis distinguishes between what are pivotal elements of the architecture and what are only design attributes. The most influential architectural concept elements form the basis for inclusion in the concept combination matrices. Reductions in concepts are first achieved through a filtering of the individual subsystem element combination matrices using the results of the architectural framework analysis and defined objectives and goals. Concept screening is then accomplished through the development of screening criteria and application of the criteria to a relative concept scoring matrix that rates the remaining system level concepts. The highest scoring concept combinations are identified for further quantitative study and potential technology investment. Applicability of the results is discussed for the formulation of a multidisciplinary design problem that can be further investigated when detailed subsystem models are developed. Thesis Supervisor: Olivier L. de Weck Title: Assistant Professor of Aeronautics & Astronautics and Engineering Systems 3