Search

This article examines how the Australian government began to formulate its approach to space research, exploring the way it approached the establishment of American tracking stations from 1956, proposals for a civilian space research program in 1959, involvement with British space research and, from 1960, the negotiations for the European Launcher Development Organisation use of rocket testing facilities at Woomera. It argues that financial and strategic considerations were foremost in the minds of the Menzies government in shaping its approach to space policy, in particular in the context of rocket testing at Woomera. Ultimately, while the decisions taken between 1956 and 1962 laid the foundations for significant and often celebrated Australian involvement in space during the 1960s, the way in which these decisions were made reflected a reluctance to be involved at all. [ABSTRACT FROM AUTHOR]

Highlights • The dynamics model and topology of Multiple Launch Rocket System(MLRS) is established using the transfer matrix method for multibody systems. • The vibration characteristics and dynamics response of MLRS is simulated, and the relevant modal test are conducted to validate the correctness of simulation. • The launch and flight dynamic simulation system for MLRS is developed, and the genetic algorithm is introduced to optimize the launch modes of rockets. • In order to optimize the launch modes of rockets, the genetic algorithm is introduced. • The relevant firing test are conducted to validate the correctness of the simulated results. Abstract This paper studies the test dynamics method of non-full loading firing for multiple launch rocket system (MLRS), and provides a new method for dynamics analysis of the MLRS coupled with rigid bodies and elastic bodies. The launch dynamics model, eigenfrequency equations and dynamics response equations of the MLRS are established using the launch dynamics and transfer matrix method for multibody systems (MSTMM). The corresponding vibration characteristics and dynamics response are simulated, and the simulated results are verified by a series of tests directly, including modal test, pulse thrust test. Then, the simulation system of launch and flight dynamics of the MLRS is developed combining the Monte Carlo simulation technology. The initial disturbance and firing precision are simulated and verified by the live firing test. On above basis, the relationship between the dynamics characteristics and firing precision of the MLRS is analyzed. And then, the test dynamics method of non-full loading firing is proposed for reducing the rocket consumption in firing precision test by optimizing the launch modes of the MLRS. Finally, a seven-shot non-full loading firing test scheme for a practical MLRS is designed. And the correctness of the scheme is proved by practical contrastive firing test. The test results show that the amount of the rockets consumption in firing precision test is reduced by 61% compared with the conventional test method. [ABSTRACT FROM AUTHOR]

Abstract A project-based course involving the design, analysis, manufacturing, testing, and launching of mid-power solid-propellant rockets over a ten-week period has been developed and taught as an approach to enhance the education and preparation of aerospace engineers at the university level. The course consists of a sequence of structured laboratory assignments that expose students to common software tools, aerospace materials, manufacturing techniques, and testing methods that directly inform and run parallel to the project. Teams of four to five students complete the project (and portions of the labs) collaboratively within an engineering competition framework. Individual students within each team are assigned specific engineering roles (e.g. design engineer, manufacturing engineer) to create an interdependence that reflects a typical integrated product team in industry and exposes students to realistic social dynamics. Student teams conduct design reviews as progressive milestones for assessment, in addition to laboratory assignments. At a per-student cost on the same order as a textbook, the project-based course combines theoretical content from several subjects with a high-order learning approach (create, evaluate, analyze) to advance the engineering skills of university students. Highlights • 10-week rocket design-build-launch course developed for aerospace education. • Project-based learning hybridized with structured laboratory sessions. • Integration of industry-relevant analytical tools, manufacturing & testing methods. [ABSTRACT FROM AUTHOR]

As a multiple-start ignition method for liquid-fuel rocket engines, the gas-dynamic igniter has many advantages, such as a simple configuration, low weight and high structural strength. However, because of the complexity of the flow of the working fluid, the details of the thermal processes involved are not clearly understood. In this study, the thermal and flow characteristics of a gas-dynamic igniter are investigated through numerical simulations using the software OpenFOAM. The simulation results show that the pressure within the igniter undergoes oscillations. The axial flow velocity decreases across the pressure wave front so that the kinetic energy of the flow is converted to thermal energy. The temperature increase within the oscillation tube of the igniter is strongly correlated with the entry mass flow. Therefore, the tube inlet area should be designed according to the igniter nozzle flow to achieve the best performance from a gasdynamic igniter. [ABSTRACT FROM AUTHOR]

A mixture of combustion products (mainly hydrogen chloride, aluminum oxide, and water) and entrained soil, referred to as Test Fire Soil (TFS), can be deposited on crops during static solid rocket motor tests. The impact of a reported worst-case event was previously evaluated by exposing corn and alfalfa to 3200-g TFS/m 2 at 54 days after emergence. Exposures via soil and leaves were evaluated separately. Reduced growth (soil exposure) and leaf “scorch” (leaf exposure) were attributed mainly to the high chloride concentrations in the TFS (56,000 mg/kg). A follow-up study was conducted to evaluate the effect of a typical deposition event (70-g TFS/m 2 , estimated by radar during several tests) and exposure (soil and leaves simultaneously) on juvenile corn, alfalfa, and winter wheat. Younger crops were used to examine potential age sensitivity differences. Impact was evaluated by comparing the growth, elemental composition, and leaf chlorophyll content of treated and untreated plants. The relationship between deposition exposure and response was also addressed. Growth of corn, alfalfa, and winter wheat exposed to a typical TFS loading was not impacted, although slightly elevated concentrations of aluminum and iron were found in the leaves. At the highest loadings used for the exposure-response experiment, concentrations of chloride and calcium were higher in TFS-exposed corn leaves than in the untreated leaves. Overall results indicate that exposure to a typical deposition event does not adversely impact juvenile crops and that younger plants may be less vulnerable to TFS. However, higher TFS loadings can cause leaf scorch and increase the leaf concentrations of some elements. [ABSTRACT FROM AUTHOR]

Under a project undertaken at NASA’s Stennis Space Center, an integrated framework has been developed for intelligent monitoring of smart elements. Integrated Systems Health Monitoring is an implementation of a monitoring system which is robust, user friendly, and adaptable. This paper focuses on smart sensors, and shows the advantage of utilizing an enhanced version of a previously developed intelligent system, DATA-SIMLAMT, called Enhanced DATA-SIMLAMT or EDATA-SIMLAMT. This new version contains additional properties and states for improved data interpretation. The additional properties are based on wavelets. The major advantage provided by adding wavelet analysis is the ability to detect sudden transitions as well as obtaining the frequency content using a much smaller data set then that required by the traditional Fourier transform method. Historically, sudden transitions could only be detected by a visual method or by offline analysis of the data. EDATA-SIMLAMT provides an opportunity to automatically detect sudden transitions as well as many additional data anomalies, and provide improved data-correction and sensor health diagnostic abilities. The newly developed system has been tested on actual rocket test data from NASA’s Stennis Space Center. [ABSTRACT FROM AUTHOR]

The review presents the author's papers on specific features of experimental development of oxygen-hydrogen liquid rocket engines (LRE), namely the 11D56, 11D57, RD0120, KVD1, and a number of propulsion units and power plants, as well as compares some data on propulsion development activities with relevant data obtained abroad. Also has been shown a role of model studies, component-level tests of engine units and systems, including those performed at simulated flight conditions, and integrated tests in support of experimental development of advanced engines and propulsion systems designed for rocket upper stages. There have been considered techniques and equipment intended to ensure safety of ground testing of rocket engines and power plants involving the use of effective diagnostic systems and emergency protection systems. [ABSTRACT FROM AUTHOR]

A finite element model is established to investigate the strength and slip characteristic of sunk screw connections in the rocket. A typical configuration is used as the basic model of parametric study to analyze the influence of pretension, friction coefficient and the angle of sunk head. It is found that with the rise of pretension force, the maximum von Mises of sunk screw connection decreases before the optimal pretension force and then increases, and the optimal pretension force can be predicted by finite element method. The friction coefficient has positive influence on structural behavior. With the rise of angle of sunk head, the maximum Von Mises increases and then decreases, and the position of stress concentration transfer from the middle of sunk screw to the lower edge of sunk head. [ABSTRACT FROM AUTHOR]

The performance characteristics of ammonium perchlorate/aluminum powder rocket motor were investigated experimentally based on a powder rocket testing system. Three-pulse experiment with one hour interval and four-pulse experiment with 15 s interval were conducted with a bi-propellant powder feed system. The experiments demonstrate the feasibility of the powder rocket for the multiple-pulse operation and the synchronization of powder feed method. The multiple-pulse performance characteristics were analyzed accordingly. It shows that the motor initiates steadily with the mass flow rate of 2.5 g/s for oxidizer powder fluidization gas and 2.0 g/s for fuel powder fluidization gas. The relative standard deviation was adopted to describe the repeatability characteristics of the pulses. The relative standard deviation of ammonium perchlorate and aluminum pistons velocity is 0.072 and 0.007, and that of oxidizer-fuel mass feed ratio is 0.052. The motor performed well with good repeatability of combustor pressure, start-up response and combustion efficiency during the multiple-pulse tests. Low frequency combustion pressure oscillations，3.6–4.2 Hz with amplitudes up to 18.7% of mean combustor pressure, were encountered. The phenomenon appeared seriously at first pulse, then alleviated at the following pulses. Further analysis of test results showed that increasing chamber pressure could ameliorate the oscillation. [ABSTRACT FROM AUTHOR]

A 70-microphone phased array, protected to withstand the harsh environment of a rocket test facility, was used to identify noise sources in the Ares I Scale Model Acoustics Test. In the unobstructed burn of a single solid rocket motor, the free-flowing plume itself was found to make a long noise source. The scenario changed completely in launch configurations where a 5%-scale model of the Ares I vehicle was tested in static firings. It was found that the impingement by the plume on various regions of the launch pad constituted the primary noise sources. The scenario is very different from current models, which assume that the plume itself is the noise source and do not account for impingement sources. As expected, the addition of water in the trench and the hole for the plume passage attenuated the associated noise sources. Water injection on the top of the pad ("rainbird") was found to attenuate only the peripheral sources around the primary plume impingement zone. The noise maps suggest that the minimization of impingement by reducing vehicle drift, reducing plume spillage via increasing the size of the hole, and covering-up leakage paths for the sound waves from the trench will attenuate the liftoff acoustics level. [ABSTRACT FROM AUTHOR]