Performance Analysis of Skip-Glide Trajectories for Hypersonic Waveriders in Planetary Exploration

A performance analysis for skip and glide is being studied to investigate the potential usage of waverider technology for interplanetary explorations. While the skip and glide equations themselves were first explored by Eggers, this thesis will implement his equations, but then add waverider technology, to determine the possibility of using trajectory assist to navigate around four planets (Earth, Mars, Jupiter and Venus). All trajectory calculations will be based on the waverider lift-to-drag ratios for various planets to determine the maximum range distance. For this research, skip and glide trajectory will be handled separately to determine which is best suited in covering the most distance for a given planet. Ballistic trajectory will only be mentioned in reference to the derivation of the skip trajectory equation, but will not be covered by itself in this research. Hence, it is possible to study a total of 98 cases of skip trajectories, 12 cases of glide trajectories and any additional cases for the four planets. Even though the skip and glide equations bear no planetary effect, all results listed in this research are based on Earth with a waverider lift-to-drag (L/D) ratio of 8.61. For a skip trajectory, the maximum number of skips is set to be 3. A high velocity ratio of 1.0 results in a low incidence angle of 0.1° with the highest range parameter of 3.52 after 3 skips. A low velocity ratio of 0.2, on the other hand, would result in a high incidence of angle of 39.5° with the least range parameter coverage of 0.05. lying the same velocity ratio and lift-to-drag to both skip and glide trajectory calculations result in a big percent difference. For example, a L/D = 8.61 and a velocity ratio (Vf) of 1.0 will have a skip range parameter of 3.52 (22,451.09 km) after 3 skips. The glide range parameter, on the other hand, comes out to be 20.60 (131,389.89 km). The percent increase turns out to be around 485.23%. Based on these numbers, it is clear that using a glide trajectory by itself would gain the most range distance for Earth

Multi-Objective Trajectory Optimization of a Hypersonic Reconnaissance Vehicle with Temperature Constraints

Temperature-constrained optimal trajectories for a scramjet-based hypersonic reconnaissance vehicle were generated by developing an optimal control formulation and solving it using a variable order Gauss-Radau quadrature collocation method. The vehicle was assumed to be an air-breathing reconnaissance aircraft that has specified takeoff/landing locations, airborne refueling constraints, specified no-fly zones, and specified targets for sensor data collections. The aircraft model included fight dynamics, aerodynamics, and thermal constraints. This model was incorporated into an optimal control formulation that includes constraints on both the vehicle as well as mission parameters, such as avoidance of no-fly zones and coverage of high-value targets. Optimal trajectories were be developed using several different performance costs in the optimal control formulation--minimum time, minimum time with control penalties, and maximum range. The resulting analysis demonstrated that optimal trajectories that meet specified mission parameters and constraints can be determined and used for larger-scale operational and campaign planning

A Survey of Gaps, Obstacles, and Technical Challenges for Hypersonic Applications

The object of this study is to canvas the literature for the purpose of identifying and compiling a list of Gaps, Obstacles, and Technological Challenges in Hypersonic Applications (GOTCHA). The significance of GOTCHA related deficiencies is discussed along with potential solutions, promising approaches, and feasible remedies that may be considered by engineers in pursuit of next generation hypersonic vehicle designs and optimizations. Based on the synthesis of several modern surveys and public reports, a cohesive list is formed, consisting of widely accepted areas needing improvement and falling under several general categories. These include: aerodynamics, propulsion, materials, analytical modeling, CFD modeling, and education in high speed flow physics. New methods and lines of research inquiries are suggested such as the homotopy-based analysis (HAM) for the treatment of strong nonlinearities, the use of improved turbulence models and unstructured grids in numerical simulations, the need for accessible validation data, and the refinement of mission objectives for Hypersonic Air-Breathing Propulsion (HABP)

A Parametric Study of Hypersonic Waverider Flight Mechanics in Optimized Trajectories during Atmospheric Entry

Over the years, many aerospace corporations and agencies have attempted to develop hypersonic vehicles. However, until recently, they have only achieved very limited success due to a lack of air-breathing hypersonic propulsion technology. Now, as technology is advancing and funds are becoming more available, aviation is once again shifting its focus towards hypersonic flight. One of many hypersonic applications is atmospheric reentry, whether reentry into Earth's atmosphere or entry into another planetary body's atmosphere. While basic theories on hypersonic reentry flight mechanics are already in use, these analyses have yet to be applied to optimizing trajectories for hypersonic waveriders in skip-glide atmospheric entry trajectories. The purpose of this research project was to provide a brief analysis of unpowered skip and glide entry trajectories and to present an optimized hypersonic waverider trajectory for a simple atmospheric reentry scenario. Five main types of unpowered glide trajectories—constant flight path angle, constant sinking speed, constant flight speed, constant dynamic pressure, and constant heating rate—were analyzed using MATLAB to model the altitude, velocity, flight path angle, and lift modulation profiles. Additionally, constant aerodynamic efficiency skip trajectories were analyzed for their ability to extend reentry ranges. The results of these analyses were then used to optimize a combined skip-glide atmospheric reentry trajectory for hypersonic waveriders about the Earth's equator. This research utilized a classical optimization approach, using MATLAB to graph the applicable design spaces for the analysis. The resulting trajectory maximizes the range of the reentry trajectory while conforming to applied maximum aerodynamic heating and maximum dynamic pressure constraints. The findings of this research will benefit the aerospace community by providing insight into hypersonic waverider performance during Earth reentry after completed space missions. This information can be used to inform flight vehicle design decisions for optimizing hypersonic waverider performance. Moreover, beyond just Earth atmospheric reentry, the analyses used in this research can also be applied to atmospheric entry into other planetary atmospheres, aiding in vehicle design and planning for interplanetary missions.The Ohio State University College of EngineeringNo embargoAcademic Major: Aerospace Engineerin

Aeronautical engineering: A continuing bibliography with indexes (supplement 262)

This bibliography lists 474 reports, articles, and other documents introduced into the NASA scientific and technical information system in Jan. 1991. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

Intelligent Autonomous Decision-Making and Cooperative Control Technology of High-Speed Vehicle Swarms

This book is a reprint of the Special Issue “Intelligent Autonomous Decision-Making and Cooperative Control Technology of High-Speed Vehicle Swarms”,which was published in Applied Sciences

Aeronautical Engineering: a Continuing Bibliography with Indexes (Supplement 244)

This bibliography lists 465 reports, articles, and other documents introduced into the NASA scientific and technical information system in September 1989. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics

DeepM&Mnet for hypersonics: Predicting the coupled flow and finite-rate chemistry behind a normal shock using neural-network approximation of operators

In high-speed flow past a normal shock, the fluid temperature rises rapidly triggering downstream chemical dissociation reactions. The chemical changes lead to appreciable changes in fluid properties, and these coupled multiphysics and the resulting multiscale dynamics are challenging to resolve numerically. Using conventional computational fluid dynamics (CFD) requires excessive computing cost. Here, we propose a totally new efficient approach, assuming that some sparse measurements of the state variables are available that can be seamlessly integrated in the simulation algorithm. We employ a special neural network for approximating nonlinear operators, the DeepONet, which is used to predict separately each individual field, given inputs from the rest of the fields of the coupled multiphysics system. We demonstrate the effectiveness of DeepONet by predicting five species in the non-equilibrium chemistry downstream of a normal shock at high Mach numbers as well as the velocity and temperature fields. We show that upon training, DeepONets can be over five orders of magnitude faster than the CFD solver employed to generate the training data and yield good accuracy for unseen Mach numbers within the range of training. Outside this range, DeepONet can still predict accurately and fast if a few sparse measurements are available. We then propose a composite supervised neural network, DeepM&Mnet, that uses multiple pre-trained DeepONets as building blocks and scattered measurements to infer the set of all seven fields in the entire domain of interest. Two DeepM&Mnet architectures are tested, and we demonstrate the accuracy and capacity for efficient data assimilation. DeepM&Mnet is simple and general: it can be employed to construct complex multiphysics and multiscale models and assimilate sparse measurements using pre-trained DeepONets in a "plug-and-play" mode.Comment: 30 pages, 17 figure

Propulsion integration of hypersonic air-breathing vehicles utilizing a top-down design methodology

In recent years, a focus of aerospace engineering design has been the development of advanced design methodologies and frameworks to account for increasingly complex and integrated vehicles. Techniques such as parametric modeling, global vehicle analyses, and interdisciplinary data sharing have been employed in an attempt to improve the design process. The purpose of this study is to introduce a new approach to integrated vehicle design known as the top-down design methodology. In the top-down design methodology, the main idea is to relate design changes on the vehicle system and sub-system level to a set of over-arching performance and customer requirements. Rather than focusing on the performance of an individual system, the system is analyzed in terms of the net effect it has on the overall vehicle and other vehicle systems. This detailed level of analysis can only be accomplished through the use of high fidelity computational tools such as Computational Fluid Dynamics (CFD) or Finite Element Analysis (FEA). The utility of the top-down design methodology is investigated through its application to the conceptual and preliminary design of a long-range hypersonic air-breathing vehicle for a hypothetical next generation hypersonic vehicle (NHRV) program. System-level design is demonstrated through the development of the nozzle section of the propulsion system. From this demonstration of the methodology, conclusions are made about the benefits, drawbacks, and cost of using the methodology

Aeronautical engineering: A continuing bibliography with indexes (supplement 293)

This bibliography lists 476 reports, articles, and other documents introduced into the NASA scientific and technical information system in July, 1992. Subject coverage includes: design, construction and testing of aircraft and aircraft engines; aircraft components, equipment, and systems; ground support systems; and theoretical and applied aspects of aerodynamics and general fluid dynamics