Space Propulsion Research Articles

Innovations in Laser-Driven Plasma Propulsion Systems for Space Exploration

Laser propulsion has emerged as a promising technology for revolutionizing space exploration by offering rapid and efficient spacecraft propulsion. This paper proposes a novel system that integrates dense corona discharge with electrical mechanisms to significantly enhance the efficiency and effectiveness of laser propulsion. Leveraging plasma physics and laser technology, this system harnesses the synergy between dense plasma and laser-driven propulsion, significantly exceeding the capabilities of conventional systems. Theoretical analysis and computational simulations reveal the potential for increased thrust, improved energy conversion efficiency, and enhanced controllability, paving the way for next-generation spacecraft propulsion technologies.

A Graphical Multi-Fidelity Gaussian Process Model, with Application to Emulation of Heavy-Ion Collisions

With advances in scientific computing and mathematical modeling, complex scientific phenomena such as galaxy formations and rocket propulsion can now be reliably simulated. Such simulations can however be very time-intensive, requiring millions of CPU hours to perform. One solution is multi-fidelity emulation, which uses data of different fidelities to train an efficient predictive model which emulates the expensive simulator. For complex scientific problems and with careful elicitation from scientists, such multi-fidelity data may often be linked by a directed acyclic graph (DAG) representing its scientific model dependencies. We thus propose a new Graphical Multi-fidelity Gaussian Process (GMGP) model, which embeds this DAG structure (capturing scientific dependencies) within a Gaussian process framework. We show that the GMGP has desirable modeling traits via two Markov properties, and admits a scalable algorithm for recursive computation of the posterior mean and variance along at each depth level of the DAG. We also present a novel experimental design methodology over the DAG given an experimental budget, and propose a nonlinear extension of the GMGP via deep Gaussian processes. The advantages of the GMGP are then demonstrated via a suite of numerical experiments and an application to emulation of heavy-ion collisions, which can be used to study the conditions of matter in the Universe shortly after the Big Bang. The proposed model has broader uses in data fusion applications with graphical structure, which we further discuss.

Hall current and ion slip effects on a ternary hybrid nanofluid flow over a bidirectional surface with chemical reaction and Cattaneo–Christov heat flux

The interaction between fluid flow and magnetic fields finds real-life applications in various industries, including semiconductors, fusion energy, plasma processing, and spacecraft propulsion. In this study, our objective is to investigate the behavior of a ternary hybrid nanofluid as it flows over a surface stretched in two directions. We consider the amalgamation of Hall current and ion slip effects, as well as homogeneous–heterogeneous reactions. The flow is influenced by Cattaneo–Christov heat flux, heat generation/absorption, and slip and convective conditions at the surface boundary. This ternary hybrid nanofluid comprises three types of nanoparticles—silicon carbide (SiC), copper oxide (CuO), and titanium oxide (TiO2)—suspended in a base fluid of diathermic oil (DO). We employ numerical methods to solve this system, utilizing the bvp4c function in MATLAB software. The results are presented graphically, demonstrating the correlation between key parameters and associated profiles. The findings reveal that the thermal profile diminishes with increasing Biot number but improves with the thermal relaxation effect. Furthermore, it is examined that the performance of the ternary hybrid nanofluid flow surpasses that of both hybrid and simple nanofluid flows. To corroborate our model, we provide a comparison with a published work in a limiting case within this study.

Regenerative Cooling Comparison of LOX/LCH4 and LOX/LC3H8 Rocket Engines Using the One-Dimensional Regenerative Cooling Modelling Tool ODREC

Due to the extreme temperatures inside the combustion chambers of liquid propellant rocket engines, the walls of the combustion chamber and the nozzle are cooled by either the fuel or the oxidizer in what is known as regenerative cooling. This study presents an indigenous computational tool developed for the analysis of heat transfer in regenerative cooling of such rocket engines. The developed tool incorporates a one-dimensional (1-D) combustion analysis to calculate the thermophysical properties of the combustion gas. Basic engine properties were calculated and used to generate a thrust chamber profile based on a bell-shaped nozzle. The hot gas side was analyzed using 1-D isentropic flow assumptions, along with heat transfer correlations. The coolant side was evaluated using the hydraulic analysis in the axial direction and the heat transfer analysis in the radial direction. Thermophysical properties and the phase of the coolant were determined using the given property tables and the instantaneous state of the coolant. This flexible and computationally less demanding tool was used to analyze two small-scale engines utilizing liquid hydrocarbon fuels, which are used in modern rocket propulsion. The wall cooling analyses of a liquid oxygen (LOX)/liquid methane (LCH4) engine and a liquid oxygen (LOX)/liquid propane (LC3H8) engine are presented. Fuel and oxidizer were used separately as coolants for both engines, and both of them experienced phase change. Results reveal the advantage of the high mass flow rate of the oxidizer in cooling performance. In addition, the results of this study show that the cooling of the LOX/LC3H8 engine is somewhat more challenging compared to the LOX/LCH4 engine.

Wave field structure and power coupling features of blue-core helicon plasma driven by various antenna geometries and frequencies

This paper deals with wave propagation and power coupling in blue-core helicon plasma driven by various antennas and frequencies. It is found that compared to non-blue-core mode, for blue-core mode, the wave can propagate in the core region, and it decays sharply outside the core. The power absorption is lower and steeper in radius for blue-core mode. Regarding the effects of antenna geometry for blue-core mode, it shows that half helix antenna yields the strongest wave field and power absorption, while loop antenna yields the lowest. Moreover, near axis, for antennas with m = +1, the wave field increases with axial distance. In the core region, the wave number approaches to a saturation value at much lower frequency for non-blue-core mode compared to blue-core mode. The total loading resistance is much lower for blue-core mode. These findings are valuable to understanding the physics of blue-core helicon discharge and optimizing the experimental performance of blue-core helicon plasma sources for applications such as space propulsion and material treatment.

Plasma Accelerator Utilizing the Medium of Near-Earth Space for Orbital Transfer Vehicles

The development of plasma accelerators for spacecraft propulsion that can capture space matter and energy shows great promise for spacecraft advancement. Such a technical approach offers a viable solution to the challenges associated with traditional rocket fuel. In the present paper, we explore the utilization of interplanetary matter as fuel for plasma thrusters on space vehicles, specifically for flights within the vicinity of Earth. Herein, solar radiation is considered a source of energy for the ionization and acceleration of particles captured from the space environment.

ANALYSIS OF FOREIGN EXPERIENCE OF DUAL USE SOLID ROCKET MOTORS

In countries, such as the United States, China, India, France, Israel and many others, solid-propellant rocket engine technologies are used not only in military missiles, but also in launch vehicles of the rocket and space industry. Such an approach of dual application of technologies makes it possible to introduce and develop new innovative solutions to increase the degree of unification of related technologies. One of the most important factors influencing the efficiency of using solid propellant rocket engines in space programs is the cost of solid rocket propellants and propulsion system components. For this reason, a high degree of unification of solid fuel products for various purposes is aimed at ensuring a high utilization of the industry’s production capacities, which can significantly reduce prices for materials, fuel and the design of propulsion systems as a whole. The analysis confirmed that the creation of launch vehicles based on rocket engines of solid fuel for military missiles naturally leads to a reduction in the time and costs for the development of such products, a reduction in technical risks and an increase in the reliability of the technologies used.

Lab-on-PCB for space propulsion: Integrated membraneless micro-ignitor for MEMS solid propellant thruster

Lab-on-PCB for space propulsion: Integrated membraneless micro-ignitor for MEMS solid propellant thruster

Calculation procedure for design parameters of transport channels of capillary in -tank devices for space propulsion systems propellant tanks

Calculation procedure for design parameters of transport channels of capillary in -tank devices for space propulsion systems propellant tanks

Exploring the potential of boron carbide in enhancing energy output of solid fuels for SFRJ and hybrid rocket propulsion systems

AbstractBoron carbide (B4C) is known for its exceptional hardness and high energy release during combustion, despite its ignition processes presents considerable challenges. This study focuses on exploring the potential of B4C as an enhancer for the energy output of solid fuels designed for hybrid rocket engines (HRE) or solid fuel ramjets (SFRJ). This study presents the successful incorporation of B4C and fluorinated PTFE (polytetrafluoroethylene) polymer into the HTPB (hydroxyl‐terminated polybutadiene) fuel matrix, aiming to enhance the ignition, combustion, and regression rate performance of solid fuel. Five different fuel compositions were formulated with varying mass ratios of B4C, and their post‐combustion products were characterized using XRD (X‐ray diffraction), HRSEM (high‐resolution scanning electron microscopy), and EDS (energy‐dispersive X‐ray spectroscopy) techniques. The HRSEM‐EDS analysis confirmed a uniform dispersion of B4C/PTFE additives throughout the HTPB matrix. To evaluate the combustion behavior of the B4C/PTFE additives, an opposite flow burner was employed with a gaseous oxygen oxidizer. The F4 fuel sample, loaded with B4C/PTFE (10/20), exhibited an average regression rate increase ranging from 0.61 to 1.15 mm/s when evaluated within the oxidizer flux range of 36–77 kg/m2s, in comparison to that of pure HTPB (0.4 mm/s to 0.76 mm/s). The ignition delay time was investigated as a key parameter affected by the B4C concentration in the solid fuel formulations. Furthermore, a comprehensive combustion mechanism is proposed and discussed for B4C/PTFE loaded in the HTPB matrix under an oxygen environment.

Thermal Characteristics Enhancement of AN/Mg/NC Composite Using Activated Carbon/Cobalt Oxide as Highly Effective Catalytic Additive

Our study examined the potential of using activated carbon/nanosized cobalt oxide (AC-Co3O4) as a new catalytic additive to improve the efficiency of the parent ammonium nitrate/magnesium/nitrocellulose (AN/Mg/NC) composite. These findings demonstrate a significant improvement in the thermal characteristics of AN/Mg/NC/AC-Co3O4 compared to the initial AN/Mg/NC. Raman spectra confirmed the multilayered nature of AC. Fourier-transform infrared spectroscopy (FTIR) analysis confirmed the presence of cobalt oxide in the synthesized additive. Differential scanning calorimetry (DSC) revealed the catalytic effect of AC-Co3O4 on the AN/Mg/NC composite, resulting in the reduction in the decomposition peak temperature (Tmax) from 277.4 °C (for AN/Mg/NC) to 215.2 °C (for AN/Mg/NC/AC-Co3O4). Thermal gravimetric analysis (TG) determined the overall mass losses (%) for AN/Mg/NC (70%), AN/Mg/NC/AC (75%), and AN/Mg/NC/AC-Co3O4 (80%). This analysis highlights the significant role of AC-Co3O4 in enhancing the energy release during decomposition. Moreover, the use of the differential thermogravimetric (DTG) technique demonstrated the two-step decomposition pathways attributed to the multi-component system. Finally, the combustion tests under the pressure of 3.5 MPa validated the catalytic efficiency of the AC-Co3O4 additive, which enhanced the burning rate (rb) of the AN/Mg/NC/AC-Co3O4 composite from 10.29 to 19.84 mm/s compared to the initial AN/Mg/NC composite. The advantageous nature of the AN/Mg/NC/AC-Co3O4 composite with a lowered decomposition temperature can be applied in rocket propulsion systems, where the precise control of combustion and ignition processes is crucial.

Rapid and Automatic Reachability Estimation of Electric Propulsion Spacecraft

Rapid and Automatic Reachability Estimation of Electric Propulsion Spacecraft

Research on solar sail attitude maneuvering method based on adaptive sliding mode control

A solar sail is a spacecraft propulsion system that uses the pressure of light to push a spacecraft. It consists of a lightweight support structure that deploys a large area of flexible film. During attitude maneuvering in space, the solar sail will excite vibrations in the flexible support structure and film, which can affect the accuracy of the attitude control system. To address this issue, this article first establishes a rigid-flexible coupled dynamic model of the solar sail that includes attitude motion and flexible structure elastic vibrations. Then, based on an adaptive sliding mode control method, a solar sail attitude maneuvering method is proposed. Finally, a numerical simulation is conducted using a hexagonal-shaped solar sail as the object. The numerical simulation results show that the attitude maneuvering method has the performance of attitude tracking and attitude stabilization, can meet the requirements of large-angle attitude maneuvering for solar sail spacecraft, and has strong robustness to model parameter uncertainty.

Propulsion Systems PNN (Non-Newtonian Propulsion)

As the facts incontrovertibly demonstrate, rocket astronautics has been unable to place permanent outposts on the Moon since the time of Apollo 11 or more than half a century ago. I don't know if you realize that today with Project Artemis NASA is trying to redo what it did over 50 years ago! The tragic failure and scrapping of the Space Shuttle (14 dead astronauts) in about 30 years of launches has in fact taught nothing to those who are about to waste more time with the inevitably failing project for rocket chemical propulsion.

Structural Stability Analysis of Underwater High-Speed Moving Vehicles in Supercavity Flow Velocity

The purpose of this paper is to analyze the structural stability of an underwater high-speed vehicle. The drag characteristics of a moving body moving at high speed in water were analyzed, and a stability analysis of the structure was performed by applying the non-conservative property according to the driven force in a rocket propulsion environment. To this end, the fluid characteristics that enable high-speed maneuvering in an underwater environment were described, and the structural stability was analyzed by simplifying modeling by increasing the resulting drag. In addition, for high-speed underwater movement, an analysis of the following force according to drag and axial load and the effect on structural stability was conducted by simplifying the structure attached to a specific location when a supercavitation occurs.

Investigation on unsteady thermal process of NEPE propellant based on an refined chemical kinetic model

This study presents a sophisticated investigation into the intricate heat and mass transfer mechanisms of NEPE composite propellant under realistic rocket motor conditions, with particular emphasis on the rapid depressurization effects. To accomplish this, we have developed an innovative particle packing algorithm coupled with a novel semi-global kinetics model. By integrating detailed chemical kinetics models for Ammonium perchlorate (AP) oxidizing powders, Cyclotetramethylene tetranitramine (HMX) oxidizing powders, and Nitroglycerin/1,2,4-Butane triol trinitrate (NG/BTTN) fuel-binder, we have constructed a meso-scale model of NEPE propellant based on comprehensive experimental data. Furthermore, a refined 9-step kinetic mechanism has been incorporated into the meso-scale model, along with a pressure drop model that accurately captures the intricate gas reaction domain. The predicted parameters of NEPE propellant have been meticulously compared with experimental results, demonstrating a remarkable level of agreement. Moreover, meticulous analyses have been carried out to investigate the complex thermal processes exhibited by this composite propellant under the challenging conditions of rapid depressurization combustion. These analyses primarily focus on unraveling the dynamic evolution of the gas-solid phase and the underlying thermal regression mechanism of the solid phase. Notably, our findings reveal intriguing temporal changes in local heat flux feedback spikes throughout the entire depressurization process, owing to the intricate topology structure of NEPE propellant, which comprises multiscale oxidizing micro-particles embedded within a fuel-binder matrix. This research significantly enhances our understanding of the thermal behavior and performance characteristics of NEPE composite propellant, thereby paving the way for future advancements in rocket propulsion technology.

Bridging the Technology Gap: Strategies for Hybrid Rocket Engines

Hybrid rocket propulsion, first demonstrated by the Russian GIRD-09 rocket in 1933, combines liquid oxidizer and solid fuel for thrust generation. Despite numerous advantages, such as enhanced safety, controllability, and potential environmental benefits, hybrid propulsion has yet to achieve its full potential in space applications. In recent years, the research on hybrid propulsion has gained enormous momentum in both academia and industry. Recent accomplishments such as the altitude record for student rockets (64 km), the launch of the first electric pump-fed hybrid rocket, and a successful 25 s hovering test highlight the potential of hybrid rockets. However, although the hybrid community is growing constantly, industrial utilizations and in-space validations do not yet exist. In this work, we reassess the possibilities of hybrid rocket engines by presenting potential fields of applications from the literature. Most importantly, we identify the technical challenges that hinder the breakthrough of hybrid propulsion in the space sector and evaluate the technologies and approaches necessary to bridge the gaps in hybrid rocket development.

Combined Cycle Nuclear System Architecture for Crewed Mars Spacecraft Propulsion and Power

Nuclear thermal propulsion can potentially reduce the time of flight and spacecraft system mass needed for human spaceflight beyond cislunar space. This nuclear propulsion system has comparable thrust capability to chemically impulsive systems, which at about twice the specific impulse, can double the delta-velocity (ΔV) for the same propellant mass. However, the canonical problem for nuclear propulsion has always been that its benefits are shadowed by low technology readiness of a complex system. This paper describes a combined cycle nuclear thermal rocket (CCNTR) system architecture for propulsion and electrical power that comprises a 42-MWt-capable nuclear reactor core to provide 9.4 kN thrust on demand at a specific impulse of 940 s. The liquid hydrogen propellant flow through the rocket chamber cools the reactor during burns, thereby producing thrust while concurrently rejecting waste heat to space. The reactor also produces up to 100 kWe power for the spacecraft, eliminating the need for solar power generation and averting challenges associated with restarting a cold reactor for propulsive burns. Radiators reject the waste heat from electrical power production. Earth-to-Mars orbital transfers less than 100 days appear feasible assuming 680,000 kg of liquid hydrogen propellant and a vehicle dry mass of 83,000 kg that includes the 13,000 kg CCNTR system. Together, these results suggest that a CCNTR could be most promising to enable crewed missions to Mars.

Удосконалення методів нагріву ксенону для запобігання потраплянню рідкої фази робочої речовини до системи подачі

Among the various types of electric propulsion, the Hall thruster type is becoming the most common. This is due to the fact that the use of a Hall thruster makes it possible to obtain high values of the thruster characteristics with a simple design compared to other types of space propulsion systems. For Hall electric propulsion thrusters, the main working substance is xenon because of its fairly high atomic weight, low ionization energy, and unreactiveness, which makes it possible to obtain high thruster characteristics with ease of operation. The use of xenon as a working substance features a peculiarity involving its critical temperature (289.74 K), which gives rise to the liquid phase in the tank and, accordingly, pressure jumps, thus making it impossible to use the xenon feed system. To exclude the ingress of the liquid phase of xenon into the accumulator tank in electric propulsion systems, heaters are placed on the xenon tank to maintain its temperature within a given range. However, this approach has the following disadvantages: the low thermal conductivity of composite tanks impairs heater-to-xenon heat transfer; warming up the whole of the tank before starting the thruster increases the thruster start-up preparation time; the continuous maintenance of the tank temperature increases energy consumption by the propulsion system; and it is impractical to maintain the temperature of the whole of the xenon, while only a few grams of it are consumed for one thruster start-up. The problem that was solved in this work consists in changing the approach to heating the working substance that enters the feed system. The analysis of literary sources showed that this problem is relevant and offers ways to improve existing methods. To solve this problem, theoretical calculations were carried out and verified by experiment. As a result, a method was proposed to calculate the gasifier so that it may maintain the temperature of the working substance entering the accumulator tank within the range from 293 K to 298 K, thus eliminating the possible ingress of the liquid phase of xenon into the accumulator tank of the feed system. This study allows one to use the proposed structural element (gasifier) instead of tank heaters, which significantly reduces power consumption and maintains the stable operation of the working substance feed system. The conclusions drawn from the study may be useful to most developers of storage and feed systems for electric propulsion systems.

Public–private partnerships in fostering outer space innovations

As public and private institutions recognize the role of space exploration as a catalyst for economic growth, various areas of innovation are expected to emerge as drivers of the space economy. These include space transportation, in-space manufacturing, bioproduction, in-space agriculture, nuclear launch, and propulsion systems, as well as satellite services and their maintenance. However, the current nature of space as an open-access resource and global commons presents a systemic risk for exuberant competition for space goods and services, which may result in a “tragedy of the commons” dilemma. In the race among countries to capture the value of space exploration, NASA, American research universities, and private companies can avoid any coordination failures by collaborating in a public–private research and development partnership (PPRDP) structure. We present such a structure founded upon the principles of polycentric autonomous governance, which incorporate a decentralized autonomous organization framework and specialized research clusters. By advancing an alignment of incentives among the specified participatory members, PPRDPs can play a pivotal role in stimulating open-source research by creating positive knowledge spillover effects and agglomeration externalities as well as embracing the nonlinear decomposition paradigm that may blur the distinction between basic and applied research.