Naval Postgraduate School
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Decision Science in the Navy Budget
No full textNPS NRP Executive SummaryThis study aimed to identify systematic behavioral biases in the Program Objective Memorandum (POM) process and accordingly propose correctional approaches intended to improve the POM process quality. The analysis framework is deeply rooted in behavioral economics, which deviates from mainstream rational economics and incorporates psychological and social influences into explanations of human behavior. We find that various cognitive biases, such as confirmation bias, anchoring effect, overconfidence bias, endowment effect, prospect theory, and herding behavior, pose a significant challenge to the Navy's ability to allocate resources efficiently and align them with strategic objectives. To enhance the integrity of the POM process and mitigate the negative impact of cognitive biases, a multifaceted approach is necessary. The recommendations we proposed encompass training and education, decision support tools, diverse decision-making teams, independent reviews and oversight, clear evaluation criteria, continuous monitoring, and strategic clarity.Approved for public release. Distribution is unlimited.This research is supported by funding from the Naval Postgraduate School, Naval Research Program (PE0605853N/2098). https://nps.edu/nrpChief of Naval Operations (CNO)N8 - Integration of Capabilities & Resource
NPS Energy Academic Group, International Fellow Add Expertise to Black Sea Maritime Forum
No full textTHE DESIGN AND ANALYSIS OF AN ADDITIVELY MANUFACTURED GYROID TRIPLY PERIODIC MINIMAL SURFACE HEAT EXCHANGER
No full textCurrent heat exchanger technology relies on conventional manufacturing techniques that limit the ability to enhance heat transfer between fluids. Advances in additive manufacturing encourage the use of complex geometries in heat exchanger design, such as Triply Periodic Minimal Surfaces (TPMS). There are many different types of TPMS geometries, but the gyroid surface was the primary area of focus in this research for its balanced thermal and hydraulic performance. The periodic nature of the gyroid surface incurs a higher friction factor and pressure losses across the geometry but also enhances heat transfer between fluids. The primary goal of this research was to design, manufacture, and test a TPMS heat exchanger to characterize TPMS heat transfer and hydraulic resistance. Additional goals included performing Computational Fluid Dynamic (CFD) studies on the gyroid surface and an analytical method was used with existing and derived correlations to calculate the expected pressure loss and heat transfer rate. It was found that a TPMS heat exchanger required a 150\% smaller volume to achieve a similar heat transfer rate compared to a conventional cross flow shell and tube heat exchanger, but at a higher pressure drop per unit length. The designed TPMS heat exchanger achieved a heat transfer rate of 25 kW.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisEnsign, United States Nav
ANALYZING THE IMPACT OF CONTRACTOR OPERATED FLIGHT TRAINING PROGRAMS ON STUDENT NAVAL AVIATOR THROUGHPUT
No full textStudents in the Naval Aviation training pipeline currently face significant waiting times, ranging from weeks to months, to begin different stages of training. There exists a compilation of issues contributing to these waiting times, related to instructor availability and aircraft maintenance, and issues exacerbated by “black swan” events such as the COVID-19 pandemic. These queues result in an inefficient use of time, waste of resources, loss of information between stages of training, and general underproduction of winged Naval Aviators. The Chief of Naval Air Training (CNATRA) has recently implemented a new program that employs civilian pilots and aircraft to train Student Naval Aviators (SNAs) in rotary aircraft, called Contractor Operated Primary Training – Rotary (COPT-R). This program aims to reduce the Naval Aviation training pipeline bottlenecks by offering students an alternative pipeline to earn their wings. Students enter this program on a voluntary basis as they are committed to learning to fly rotary aircraft only. Through coordination with CNATRA, this thesis implements current data into an aggregate discrete-event simulation that models the status of the pipeline. The approach implements queueing and simulation methods to determine the effects of modifying the percentage of students in COPT-R to achieve the best reduction in wait times across all pipelines.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States NavyNPS Naval Research ProgramThis project was funded in part by the NPS Naval Research Program
CONSTRUCTION, FLOW SIMULATION, AND VALIDATION OF A MACH 5+ HYPERSONIC WIND TUNNEL
No full textHypersonics has been listed as a research priority by the Department of Defense for the past seven years. The Naval Postgraduate School has analyzed the design of a Mach 5+ hypersonic wind tunnel that would allow for long-runtime, hypersonic data to be collected at a range of high-Mach number flows. The significance of such a tunnel is the ability to get experimental validation of hypersonic flow simulations as well as providing a consistent and robust testing facility for air and spacecraft designs, such as re-entry vehicles. This paper details the construction and validation of a hypersonic tunnel capable of supporting these high-Mach number flows. The assembly process and design rationale are included, as well as the operating instructions of the valve and heater. This paper presents supporting flow simulations of the entire wind tunnel system. Finally, recommendations for future work and the project status of the Naval Postgraduate School’s Mach 5+ wind tunnel are given.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
2025 ASSESSMENT OF THE SENIOR ENLISTED PROGRAM AT THE UNITED STATES NAVAL ACADEMY
No full textThis thesis revisits Captain (Ret.) David K. Richardson’s (2000) assessment of the Senior Enlisted Leader (SEL) Program at the United States Naval Academy (USNA). Based on 34 focused interviews, Richardson's study identified eight key themes, six highlighting positive aspects of the program and two addressing areas for improvement. His findings suggested that the SEL Program significantly contributed to midshipmen leadership development and had a lasting impact on USNA.This study addresses the research question: How effectively is the SEL Program implemented and perceived across stakeholder groups at USNA? Using a mixed-methods exploratory design, the study gathered survey data from SELs, Battalion Officers, and midshipmen, and conducted interviews with senior Academy leadership. Thematic and statistical analyses identified six central challenges: role ambiguity, inconsistent evaluation, variable integration, underutilized mentorship potential, gaps in professionalism, and inadequate onboarding.Despite these issues, SELs were viewed as valuable leadership mentors, particularly when well-integrated. The findings suggest that program success varies widely due to a lack of standardization. The study concludes with recommendations to formalize SEL onboarding, clarify roles, enhance training, and establish feedback mechanisms. These improvements aim to strengthen the SEL Program’s institutional alignment and reinforce its value as a developmental asset in officer education.Distribution Statement A. Approved for public release: Distribution is unlimited.Chief Petty Officer, United States NavyLieutenant, United States NavySenior Chief Petty Officer, United States Nav
INTEGRATION OF MODELS TO ENHANCE THE VERIFICATION PROCESS OF NUCLEAR SYSTEMS
No full textThe lack of integration between computer-aided engineering (CAE) and model-based systems engineering (MBSE) tools hinders the assessment of how design changes affect system requirements. To address this challenge, this thesis proposes a model breakdown structure methodology implemented using MathWorks’ System Composer to integrate MBSE and CAE models. The Brazilian Multipurpose Reactor is used as a case study to demonstrate the effectiveness of the proposed methodology. An enhanced, automated verification process is achieved by linking system requirements to a finite element analysis that calculates fuel and cladding temperature distributions in a slow loss of flow accident scenario. First, a Latin hypercube design is employed to evaluate how variations in design factors influence cladding temperature. Second, the Wilks’ theorem is applied to calculate the maximum response with a 95% confidence level and 95% probability. The results indicate that the 95/95 upper limit of the peak cladding temperature remains below the onset of nucleate boiling. Furthermore, the integrated model is expected to significantly reduce the effort required for uncertainty quantification.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisCapitão de Corveta, Brazilian Nav
COST EFFECTIVENESS ANALYSIS FOR CAPITALIZING UNIT-LEVEL SHIP INVENTORIES
No full textSome U.S. Navy ships operate under Navy Working Capital Fund (NWCF) while others are mission funded. This thesis evaluates the feasibility, cost implications, and operational impacts of transitioning Navy ship inventories from mission-funds to the Navy Working Capital Fund. This study builds upon prior research by expanding the data set and incorporating updated logistics performance metrics. Using a Cost Effectiveness Analysis via the Multi-Objective Decision-Making framework, the study analyzes 30 months of supply effectiveness data, inventory valuation, and manning data. In addition to quantitative analysis, this thesis also incorporates qualitative analysis of procedural, policy, and cultural factors that influence transition feasibility. The analysis includes a cost estimate for inventory capitalization, an assessment of system compatibility, and a phased implementation aligned with the Optimized Fleet Response Plan. The findings show that NWCF platforms consistently outperformed mission-funded counterparts in terms of supply responsiveness and funding availability, particularly during periods of high operational demand. The projected annual transition cost was modest, with no major system or procurement disruptions identified. By combining quantitative and qualitative insights, this study provides a data-driven framework for Navy leadership to evaluate a potential enterprise-wide transition of unit-level ship inventory funding to the NWCF model.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Commander, United States NavyLieutenant Commander, United States NavyLieutenant Commander, United States Nav
APPLICABILITY OF HYDROGEN FUEL IN SMALL GAS TURBINES
No full textThe trend for the demand of power and energy has increased and continues into the future. The utilization of alternative fuels such as hydrogen could decrease the dependence on hydrocarbon fuels while maintaining performance. This research considered the Capstone C30 Microturbine and its performance using hydrogen as a fuel compared to propane. Modification and upgrades were conducted as necessary for operation and testing. The research was conducted and investigated experimentally, collecting data, and analytically, using Computational Fluid Dynamics (CFD). From the research, gas turbines such as the C30 can be operated on hydrogen fuel successfully. Analytical models were further refined so as to be able to model the operation of the C30 at design and off-design.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States NavyOffice of Naval Research, Arlington, VA 22203 under the NextSTEP Progra
Faces of NPS: Lt. Col. Devin Smiley, USMC (Ret)
No full textFaces of NPS features interviews spotlighting the students, faculty, staff and alumni of our Nation's premier defense education and research institution