Missile Engine Research Articles

Time-to-go based three-dimensional multi-missile spatio-temporal cooperative guidance law: A novel approach for maneuvering target interception

This research presents a novel approach called 'Time-to-target-based multi-missile spatio-temporal cooperative guidance' This approach enables the simultaneous guidance of multiple missiles, allowing them to intercept a maneuvering target from different terminal intercept angles to maximize damage. The article introduces a finite-time optimal cooperative guidance technique to reduce the load on missile engines in the line-of-sight (LOS) direction. It proposes a time-varying sliding mode guidance scheme, which is parameterized by the remaining flight time, for both longitudinal and lateral LOS directions. The scheme helps prevent excessive initial acceleration in the longitudinal and lateral LOS directions while ensuring intercept angle constraints. The time-varying cooperative guidance law proposed in this study enables the simultaneous interception of a maneuvering target with different terminal intercept angles at the moment of terminal intercept. The numerical simulation results indicate that the multi-missile spatio-temporal cooperative guidance method is effective, superior, and robust. The method enables multiple missiles to achieve the minimum acceptable intercept distance at different terminal intercept angles while optimizing fuel in the LOS direction.

Exploring Theoretical Fundamentals of a Physical-Mathematical Model for Unsteady Combustion in Solid Rocket Fuel and Developing Methods for Unsteady Velocity Calculation

The article is dedicated to the theoretical study of the non-stationary Combustion Velocity of Solid Rocket Fuel (CVSRF). To calculate the Internal Ballistic Characteristics (IBC) of solid fuel missile engines, combustion velocity laws are used. These laws represent stationary relationships between the Combustion Velocity of Solid Rocket Fuel (CVSRF) and initial pressure and temperature. These relationships are experimentally determined under “stationary” conditions, i.e., by burning fuel samples in stationary conditions.

Implementation of Passing Vehicle Search Algorithm for Optimization of WEDM Process of Nickel-Based Superalloy Waspaloy.

Nickel-based superalloys find their main use in missile engines, atomic devices, investigational aircraft, aerospace engineering, industrial applications, and automotive gas turbines, spacecraft petrochemical tools, steam power, submarines, and broader heating applications. These superalloys impose certain difficulties during the process fabrication owing to their levels of higher hardness. In the current study, the precise machining of Waspaloy was attempted through the wire electrical discharge machining (WEDM) technique. A multi-objective optimization has been performed, and the influence of multi-walled carbon nanotubes (MWCNTs) has been assessed using the passing vehicle search (PVS) algorithm. The effects of machining variables like current, Toff, and Ton were studied using the output measures of material removal rate (MRR), recast layer thickness (RLT), and surface roughness (SR). The Box-Behnken design was applied to generate the experimental matrix. Empirical models were generated which show the interrelationship among the process variables and output measures. The analysis of variance (ANOVA) method was used to check the adequacy, and suitability of the models and to understand the significance of the parameters. The PVS technique was executed for the optimization of MRR, SR, and RLT. Pareto fronts were derived which gives a choice to the user to select any point on the front as per the requirement. To enhance the machining performance, MWCNTs mixed dielectric fluid was utilized, and the effect of these MWCNTs was also analyzed on the surface defects. The use of MWCNTs at 1 g/L enhanced the performance of MRR, SR, and RLT by 65.70%, 50.68%, and 40.96%, respectively. Also, the addition of MWCNTs has shown that the machined surface largely reduces the surface defects.

Investigation on repairing 30CrMnSiNi2A steel with laser additive and subtractive hybrid remanufacturing technology

The 30CrMnSiNi2A ultra-strength steel features excellent comprehensive mechanical properties and has been widely used to manufacture structural parts such as the aircraft landing gear, the wing girder, the missile engine shell, etc. However, wear and defects are produced on the surface of these parts in the course of their long-term service. In this paper, a continuous-wave laser deposition and pulsed laser finishing hybrid technique was proposed to repair 30CrMnSiNi2A ultra-high strength steel. The microstructure and mechanical properties of 30CrMnSi2A alloy matrix, laser repairing and laser finishing parts were compared. Laser finishing parameters were optimized to further improve the surface properties of the repaired parts. The effect of different process parameters on the surface morphology, microstructures, micro-hardness and wear resistance was explored. The results revealed that the comprehensive surface properties of repair parts with an average surface roughness of 1.12 µm, a micro-hardness of 595.22HV and a wear rate of 4.78 × 10−3 mm3/N·m can be obtained with laser finishing. And, the surface roughness and wear rate were reduced by 64.96% and 27.68% respectively, and the micro-hardness can be improved 23.67% compared with the parts without laser finishing.

How Missile Engineering is Taking Product Line Engineering to the Extreme at Raytheon

AbstractThis paper describes a new approach to designing and building missiles by Raytheon Missile and Defense Systems. Key aspects of the approach include (1) modular common components connected through identified standards, (2) modular open systems approaches and standards based interfaces, (3) Feature‐based Product Line Engineering (FbPLE) practices for identifying commonality and managing variation, and (4) implementing digital transformation through digital engineering capabilities to begin a missile's digital twin. Much more ambitious than simply reusing existing component designs from previously built missiles, this approach involves automatic generation, exploration, and pruning of an automatically generated trade space of possible missile designs that satisfy a given set of requirements. The goal is to radically lower development and production costs by rapidly settling on a viable design that can be taken to design validation, then complete design and production, all in a digital ecosystem. The paper focuses on the FbPLE aspect of the engineering approach and shows how its technology is used to create and manage the trade space, and then create a digital twin of a chosen design.

Introduction to Neutrosophic Reliability Theory

Reliability is one of the most important indicators of the quality of any system or product, ranging from the simplest machines as a product in any factory to the most complex system, such as phone or aircraft or missile engines, etc. The accuracy of these products indicates their high reliability, and therefore the customer or business owner will have confidence in products and will request more quantity. To reach the highest level of accuracy for the reliability of any system, the corresponding data must be very accurate. For this purpose, we proposed to add accuracy to reliability by adding data that contains more pieces of information about a specific product or problem. We introduced a new logic (Neutrosophic logic) of data instead of classical logic which gives us more accuracy of data that contain indeterminacy such as extremist, vague, and unclear data. We defined the neutrosophic reliability according to the modern neutrosophic logic by constructing a neutrosophic reliability function. We have used the type of series as an application of neutrosophic reliability and introduced some examples. Neutrosophic reliability theory can be applied in computer science and decision support systems.

Development of a computational mesh generator for the OpenFOAM software environment used at industrial enterprises

The paper is devoted to special features of the development of an application with a graphical user interface to prepare computational meshes (CMs), when performing numerical simulation based on the OpenFOAM software environment (SE), used at enterprises of missile engineering, automobile industry, engine building, shipbuilding and other industries. OpenFOAM, if used, permits successfully conducting numerical simulation in the phase of engineering of finished goods through 3D modelling of deformable solids, investigation of their characteristics, when interacted with liquid and gaseous media, and also study of mechanics of deformable solids that correspond to the models. The paper provides the comparative characteristics of available software with a graphical user interface mainly used to prepare CMs and the revealed drawbacks of the software. The urgency of an issue is highlighted, special features of the development of the new application are given. The study scientific novelty that lies mainly in the enlargement of a list of types of CMs available for preparation through a graphical user interface, and possible operation with any number of mesh models in one OpenFOAM case, is defined. The program has a certificate №2018616380 dated May 30th, 2018 on registration by Federal Institute of Industrial Property.

Experimental Taguchi approach and Gray–Taguchi optimization on mechanical properties of aluminum 8011 alloy sheet under uniaxial tensile loads

Abstract Aluminum alloys are making a special consideration for extreme temperature applications in service background of aircraft structures, missile engines, and pressure containers. This creates crucial to recognize various mechanical properties of the Al 8011 alloy such as yield strength (ys), % of elongate and ultimate strength (uts) have been valued by depleting uniaxial tensile loads. The mechanical properties of aluminum alloy materials are purely reliant on the rate at which the part is heated and quenched. The tensile experiments are accompanied at 150 °C and 450 °C with different strain conditions (0.1 s−1, 0.001 s−1) to find the material behavior of Al 8011 alloy sheet. The Taguchi orthogonal array and the (S/N) signal to noise ratio are used to analyze the effect of elected process considerations and their levels.

Independent component analysis enhanced pulse thermography for high silicon oxygen phenolic resin (HSOPR) sheet with subsurface defects

As an important part of solid-propellant missile engine, the quality assurance of cladding layer ‘high silicon oxygen phenolic resin (HSOPR) sheet’ is very important. In this paper, independent component analysis enhanced pulse thermography (ICA-PT) was introduced to detect the subsurface defect of HSOPR. The basic principle of ICA was described. The experiment of HSOPR sheet with simulated flat bottomed holes (FBHs) detected by ICA-PT was carried out. Moreover, the comparative experiments of different algorithms such as pulse phase thermography, continuous wavelet transform and principal component analysis were carried out. The SNR of the characteristic image was analyzed. The experimental results demonstrated that ICA algorithm can improve the detection SNR significantly. Therefore, the research on ICA-PT is of significant importance to quantitative evaluation the quality of the high silicon oxygen phenolic resin sheet.

Dynamic thermal tomography based on continuous wavelet transform for debonding detection of the high silicon oxygen phenolic resin cladding layer

Photothermal diffusion-wave imaging and thermal tomography are promising techniques for the analysis of debonding detection of the solid-propellant missile engine. In this paper, the dynamic thermal tomography based on continuous wavelet transform (CWT-DTT) was introduced to detect the defect and reconstruct the 3D (three-dimensional) visualization of the high silicon oxygen phenolic resin cladding layer. The basic principle of CWT-DTT and the tomography processing were described. Moreover, 3D thermal wave model stimulated by pulse signal was developed. The relationship between the SNR of the feature image and the scale factor of CWT was analyzed. The tomography experiment of cladding layers with simulated flat bottomed holes (FBHs) defects by CWT-DTT was carried out. The experimental results demonstrated that the measuring depth of all FBHs has a good agreement with the actual depth. Therefore, the research on CWT-DTT is of significant importance to quantitative evaluation the quality of the high silicon oxygen phenolic resin cladding layer.

Pulse Phase Dynamic Thermal Tomography Investigation on the Defects of the Solid-Propellant Missile Engine Cladding Layer

Pulse phase dynamic thermal tomography (PP-DTT) was introduced as a nondestructive inspection technique to detect the defects of the solid-propellant missile engine cladding layer. One-dimensional thermal wave mathematical model stimulated by pulse signal was developed and employed to investigate the thermal wave transmission characteristics. The pulse phase algorithm was used to extract the thermal wave characteristic of thermal radiation. Depth calibration curve was obtained by fuzzy c-means algorithm. Moreover, PP-DTT, a depth-resolved photothermal imaging modality, was employed to enable three-dimensional (3D) visualization of cladding layer defects. The comparison experiment between PP-DTT and classical dynamic thermal tomography was investigated. The results showed that PP-DTT can reconstruct the 3D topography of defects in a high quality.

Retrospective Identification of the Virtual Analogues of Ballistic Missiles

Разработка ракет как сложных технических изделий требует системного анализа проектных параметров, тактических, эксплуатационных и технических характеристик реальных ракет, прошедших все этапы жизненного цикла: разработка, производство, испытания, эксплуатация. Одним из эффективных методов решения таких задач является анализ конструкторской и технологической документации, а также конкретных образцов изделий. Если по объективным причинам это невыполнимо, необходимо воссоздать виртуальные аналоги ранее созданных ракет. Наиболее подходящим для этих целей является метод ретроспективной идентификации, заключающийся в имитационном моделировании исследуемых ракет с последовательной детализацией их параметров. Рассмотрен процесс идентификации виртуальных аналогов одноступенчатых баллистических ракет - от анализа «уравнения существования» до имитационного моделирования траектории полета управляемой одноступенчатой баллистической ракеты с вертикальным стартом и программным изменением угла тангажа и угла атаки. Приведены параметры и характеристики виртуальных аналогов одноступенчатых баллистических ракет: 11 ракет с двигателями на жидких криогенных топливах; 13 ракет с двигателями на жидких высококипящих топливах; 12 ракет с двигателями на твердых топливах. Для ракет с ЖРД методом наименьших квадратов получены полиномы, определяющие зависимости от максимальной дальности полета, минимальных и средних значений относительных масс топлива и конструкции двигательной установки.

Технологии информационной поддержки жизненного цикла бортовой радиоэлектронной аппаратуры ракетно-космической техники

Технологии информационной поддержки жизненного цикла бортовой радиоэлектронной аппаратуры ракетно-космической техники

Comparative Studies on Various Turbulent Models with Liquid Rocket Nozzle through Computational Tool

Supersonic flows associated with missiles, aircraft, missile engine intake and rocket nozzles are often steady. In this present work, the computational analysis was conducted on C-D (convergent –divergent) nozzle for understanding the flow regime with various flow properties such as velocity and various turbulent models (spalert almaras, K-ε and K-ω). The Scale down model of C-D nozzle was chosen for this study and it was modelled computationally with Gambit software package. In this integrated component model, the inlet flow is assumed a two-dimensional, steady, compressible, turbulent and supersonic. The physics based mathematical model of the considered flow consists of conservation of mass, momentum and energy equations subject to appropriate boundary conditions as defined by the physical problem stated above. The system of the governing equations with turbulent effects is solved numerically using different turbulence models to demonstrate their numerical accuracy in predicting the characteristics of turbulent gas flow in such complex geometry. Fluent software package was used for solving gas flow equations with turbulence models. The Mach number was chosen for different cases of analyses were 1.2, 1.5 and 2. For each case, different turbulence were engaged and solved and all the results were compared finally.

The Design Research of Millimeter-Wave Homing Empty - Empty Ammunition Ballistics

The millimeter-wave terminal guidance ammunition monitoring scanning field is small. The modified design is in order to improve the search section trajectory guidance. This study established seeker search area to capture the target model, which leads to the missile engine unpowered glide distance formula after flameout. At the millimeter-wave terminal on the missiles contraction section ballistic. Each missile is designed for the flat road, the swash decline ballistic programs. Flat missile road program scans and does not shrink. Its flight speed falls and declines rapidly, has different gliding distance and terminal velocity. After the missile engine is flameout, its start-gliding speed is great. Ramp fell ballistic program enhances the air-air (or air-ground) guided missile’s gliding ability, helping to improve range. But shortcomings are that target tracking scanning domain contracts. Using the seeker optical axis in the pitch direction can achieve accurate positioning with the height precession. Two ballistic designs can both meet the target seeker’s scanning, thus effectively improve the striking precision.

Research on the Damage Effect to Supersonic Missile Engine Cabin by Discrete Rod Warhead

For study the damage effect of discrete rod warhead to supersonic missile engine cabin, the rods attacking the supersonic missile engine cabin were simulated by using ANSYS / LS-DYNA software. Acquired the influence rules that the postures of the rods and the number of the rods attacking the target to damage the supersonic missile engine cabin. The results show: the postures of the rods have great influences to damage the supersonic missile engine cabin; When the rods are straight circular permutation, the rods have the best damage effect to engine cabin; the smaller of the angle between the rods vertical axis and the engine cabin vertical axis, the damage ability is the strongest. Really not the more number of the rods attack into the supersonic missile engine cabin, the damage effect is the better; contrasted the conditions with the same rotation angles, the damage effect to engine cabin, the conditions of 4 rods attacking into the engine cabin are better than the conditions of 5 rods attacking into the engine cabin.

Hybrid Carbon-Carbon Ablative Composites for Thermal Protection in Aerospace

Composite materials have been steadily substituting metals and alloys due to their better thermomechanical properties. The successful application of composite materials for high temperature zones in aerospace applications has resulted in extensive exploration of cost effective ablative materials. High temperature heat shielding to body, be it external or internal, has become essential in the space vehicles. The heat shielding primarily protects the substrate material from external kinetic heating and the internal insulation protects the subsystems and helps to keep coefficient of thermal expansion low. The external temperature due to kinetic heating may increase to about maximum of 500°C for hypersonic reentry space vehicles while the combustion chamber temperatures in case of rocket and missile engines range between 2000°C and 3000°C. Composite materials of which carbon-carbon composites or the carbon allotropes are the most preferred material for heat shielding applications due to their exceptional chemical and thermal resistance.

Investigation of the Oxidizer Charge Impact Onto Energetic Characteristics Demonstrated by the Stream of Gunpowder Gas Ejected by Solid-Propellant Missile Engines

Abstract The study discloses outputs from examinations devoted to charges of oxidizers and their impact on behaviour of missile engine operation with particular attention to measures that are undertaken to counteract stall of a helicopter engine. Homogenous solid propellant for missile engines exhibits a negative oxygen balance. When a series of rocket missiles driven by means of such fuel is launched from the helicopter board there is a hazard of the engine stall effect that may lead to killing its engines. Admixture of potassium (II) sulphate (VI) that is added into the combustion chamber of a missile engine as an inhibitor of the combustion reaction favourably alters characteristics of the engine output power and, at the same time, is irrelevant to the available thrust of the engine. Application of the oxidizer as an insert into the engine substantially improves flight safety when rocket missiles are launched from an aircraft and makes it possible to avoid significant changes in the engine design. The paper outlines the results from investigations when a charge of K2SO4 was introduced into the Mk66 missile engine as a compressed bar and the working parameters of the engine were measured. The investigations on a vertical workbench comprised measurements of the engine thrust and temperature in the stream of exhaust gases. The measurement results were compared against figures sourced from the original data sheets of engines

Field‐scale evaluation of a biobarrier for the treatment of a trichloroethene plume

AbstractIn the 1960s, trichloroethene (TCE) was used at what is now designated as Installation Restoration Program Site 32 Cluster at Vandenberg Air Force Base to flush missile engines prior to launch and perhaps for other degreasing activities, resulting in releases of TCE to groundwater. The TCE plume extends approximately 1 kilometer from the previous launch facilities beyond the southwestern end of the site. To limit further migration of TCE and chlorinated degradation by‐products, an in situ, permeable, reactive bioremediation barrier (biobarrier) was designed as a cost‐effective treatment technology to address the TCE plume emanating from the source area. The biobarrier treatment would involve injecting carbon‐based substrate and microbes to achieve reductive dechlorination of volatile organic compounds, such as TCE. Under reducing conditions and in the presence of certain dechlorinating microorganisms, TCE degrades to nontoxic ethene in groundwater.To support the design of the full‐scale biobarrier, a pilot test was conducted to evaluate site conditions and collect pertinent design data. The pilot test results indicated possible substrate delivery difficulties and a smaller radius of influence than had been estimated, which would be used to determine the final biobarrier well spacing. Based on these results, the full‐scale biobarrier design was modified. In January 2010, the biobarrier was implemented at the toe of the source area by adding a fermentable substrate and a dechlorinating microbial culture to the subsurface via an injection well array that spanned the width of the TCE plume.After the injections, the groundwater pH in the injection wells continued to decrease to a level that could be detrimental to the population of Dehalococcoides in the SDC‐9TM culture. In addition, 7 months postinjection, the injection wells could not be sampled due to fouling. Cleaning was required to restore their functions. Bioassay and polymerase chain reaction analyses were conducted, as well as titration tests, to assess the need for biobarrier amendments in response to the fouling issues and low pH. Additionally, slug tests were performed on three wells to evaluate possible localized differences in hydraulic conductivity within the biobarrier. Based on the test results, the biobarrier was amended with sodium carbonate and inoculated a second time with SDC‐9TM. The aquifer pH was restored, and reductive dechlorination resumed in the treatment zone, evidenced by the reduction in TCE and the increase in degradation products, including ethene. © 2011 Wiley Periodicals, Inc.

Advanced Ni base superalloys for small gas turbines

Ni base superalloy cast materials provide an outstanding balance of high temperature strength, fatigue resistance, oxidation resistance and coating performance, and can be produced to very tight tolerances in extremely complex configurations, such as axial and centrifugal integral cast turbine wheels. As a result, cast superalloys are used in the most demanding applications of aero and industrial gas turbine engines. Use of these materials is expanding to smaller microturbine, turbojet, turbocharger and missile engine applications due to this unique combination of desirable properties. This paper will present an overview of the application of investment cast Ni base superalloys and process capability to small turbine and missile engines.Les matériaux moulés de superalliage à base de Ni fournissent une balance exceptionnelle de résistance à haute température, de résistance à la fatigue, de résistance à l’oxydation et de performance du revêtement. On peut également les produire à des tolérances très serrées dans des configurations extrêmement complexes, comme des roues de turbine à coulée axiale et centrifuge d’une seule pièce. Conséquemment, les superalliages moulés sont utilisés dans les applications les plus exigeantes des turbines à gaz aéro- et industrielles. L’utilisation de ces matériaux s’étend à des applications de plus petite micro turbine, de turboréacteur, de turbocompresseur et de moteur de missile grâce à cette combinaison unique de propriétés désirables. Ce document présente une revue de l’application des superalliages à moulage de précision à base de Ni et de la capacité opérationnelle du processus pour les petites turbines et les moteurs de missile.