Browse Topic: Rocket engines

Items (342)
Hypersonic propulsion would allow for air travel at speeds of Mach 6 to 17, or more than 4,600 to 13,000 miles per hour, and has applications in commercial and space travel
In the fall of 2023, NASA hot fire tested an aluminum-based, 3D-printed rocket engine nozzle. What made the event remarkable is that aluminum isn’t typically used for additive manufacturing because the process causes it to crack, and it isn’t used in rocket engines due to its low melting point. Yet the test was a success
Engineers at NASAs Stennis Space Center have developed the HYdrocarbon Propellants Enabling Reproduction of Flows in Rocket Engines (HYPERFIRE), a sub-scale, non-reacting flow test system. HYPERFIRE uses heated ethane to enable physical simulation of rocket engines powered by a broad range of propellants in an inexpensive, accurate, and simple fashion
Airplane turbines and rocket engines are very powerful, hot and noisy and yet in need of extremely sensitive measurement technology. And they have another thing in common: They are most efficient when they run on a constant and even flame. Specialized measurement technology helps aerospace engineers improve combustion chambers and fuel injectors. In Switzerland, two ambitious student organizations have been using iterative pressure measurements to develop and build a significantly more efficient next generation of rocket engines
In any human space flight program, safety of the crew is of utmost priority. In case of exigency in atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew Escape System (CES). CES is a critical part of the Human Space Flight which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the CES during the mission abort are severe as the propulsive, aerodynamic and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight period considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters. Depending on the time of abort, the ignition delay of PM, LEM and HEM
S, SubashBabu P, GirishDaniel, Sajan
This paper presents a study of numerical cold flow analysis of double-base swirl injector design using Ansys Fluent. The study focuses on the design validation and development of double-base liquid-liquid swirl injector for Ethanol(Fuel) and Hydrogen Peroxide(Oxidizer) based liquid propellant rocket engine. The green propellant contains 80% Ethanol (C2H5OH) as fuel and 60% Hydrogen Peroxide (H2O2) as oxidizer. A comprehensive data, obtained from NASA CEARun code, of performance parameters and carbon monoxide and carbon dioxide emission of most commonly used propellant is compared with ethanol and hydrogen-peroxide based propellant is presented for reference. Secondly, the paper presents the theoretical design model of Swirl Injector, and numerical cold flow study of swirl injector model. For this the 3D models of fuel and oxidizer swirl nozzles are designed separately as per the theoretical design parameters. Poly-hexacore type fluent meshing is used to generate valid mesh. A 3-D
Kumar, G. DineshAgarwal, Abishek Garg
L3Harris Technologies Melbourne, FL 585-465-3592
Skoltech engineers have used a 3D printer to fabricate — and investigate the mechanical characteristics of — samples of bronze-steel alloys previously unknown to materials science. Blending the distinct properties of bronze and steel, the novel alloys could be used to manufacture combustion chambers for aircraft and rocket engines. These would benefit from both steel’s ability to withstand extreme temperatures and bronze’s capacity to conduct heat away from the chamber
This SAE Aerospace Information Report (AIR) includes all missile and launch vehicle actuation systems, including electrohydraulic, electropneumatic, and electromechanical types. The data for many systems are not complete. As more information becomes available, periodic updates will be issued to complete existing data sheets and to add new ones. An index by type of vehicle and by type of actuation system is included. The actual data sheets in the body of the report are organized in alphabetical order
A-6B1 Hydraulic Servo Actuation Committee
This document defines and illustrates the process for determination of uncertainty of turbofan and turbojet engine in-flight thrust and other measured in-flight performance parameters. The reasons for requiring this information, as specified in the E-33 Charter, are: determination of high confidence aircraft drag; problem rectification if performance is low; interpolation of measured thrust and aircraft drag over a range of flight conditions by validation and development of high confidence analytical methods; establishment of a baseline for future engine modifications. This document describes systematic and random measurement uncertainties and methods for propagating the uncertainties to the more complicated parameter, in-flight thrust. Methods for combining the uncertainties to obtain given confidence levels are also addressed. Although the primary focus of the document is in-flight thrust, the statistical methods described are applicable to any measurement process. The E-33 Committee
E-33 In Flight Propulsion Measurement Committee
Inflatable and deployable beams and masts such as solar sail supports used in space missions are often made of polymer composites and may be stored for one to two years in space before deployment. While stored, these polymer composites degrade on a molecular level, which can limit the ability of the beams to unfurl properly, reducing performance or even failing to unfurl. Researchers at NASA’s Langley Research Center developed a fiber-reinforced polymer composite to reduce the effect of viscoelastic creep and prolong the molecular integrity of polymer-based beams over time
Laser Beam Welding (LBW) is one of the advanced methods of joining metals by fusion. The LBW process exhibits comparatively better welding performance than conventional processes and this method of welding approach is exclusively employed in higher volume applications such as automotive industries. One of the most common nickel alloys used in various engineering fields is Inconel 718. This material has high strength and corrosion resistance properties, and is commonly used in high-temperature applications, such as gas turbines and rocket engines. In this study, we aim to develop an artificial intelligence tool that can analyze the influence of various process variables on the design and performance of a metal. The experiments were planned using the design approach of Taguchi. An L27 orthogonal array was used for the experiments. The three performance measures are the top width, bottom width, and penetration. The influence of the process parameters on the selected performance was
Pasupuleti, ThejasreeNatarajan, ManikandanKrishnamachary, PCR, RameshKatta, Lakshmi Narasimhamu
It’s no longer a question of when metal additive manufacturing (AM)—and particularly metal laser powder-bed fusion (LPBF)—will become an accepted, reliable production technology, particularly in aerospace and defense. This is already the case now. Over the past 18 months a host of aerospace leaders, OEMs, startups, and contract manufacturers (CMs) alike have purchased, or begun outsourcing work to, advanced AM systems. They’re confidently producing end-use, 3D-printed parts—and sometimes entire rocket engines
This paper studies the “Experimental testing of spray characteristics of swirler injector without guide vanes in Liquid Propellant Rocket Engines”. The purpose of a fuel injector is to inject and control the flow of the propellants into the combustion chamber. It consists of Tangential ports, a swirls chamber, a converging spin chamber, and a discharge orifice. Kerosene as fuel and liquid oxygen as oxidizer were employed here. To pressurize the propellants, nitrogen gas is used and the pressurized pipeline is controlled with an open/close ball valve and measure the inlet pressure using a pressure gauge. When a propellant comes through the inlet has a tangential velocity and it causes the propellants to swirl inside the swirl chamber at the exit the propellant comes with rotational momentum and forms a liquid film and then the friction between the propellant and air accelerates and disrupts the liquid film and converts into very tiny droplets. The exit mass flow rate, spray cone angle
Gangarapu, YagnatejaASADALI, KOLARPavuluri, LeelamanideepKumar, Dinesh
Letter from the Guest Editors
Rajpathak, DnyaneshRoboff, MarkYu, HuafengBiswas, Gautam
The collision of two or more liquid jets may provide considerable atomisation and efficient mixing of injected substances at the same time. This phenomenon is used, among others, in rocket engines, where the fuel and oxidiser are introduced separately and almost immediately mixed through self-impingement. Depending on the injection and operating conditions, diverse configurations of impinging jets are used, such as doublets, triplets, etc. The appropriately designed injectors and operating conditions ensure the short length of the liquid structures that are developed as a result of the jets’ collision, as well as lead to intensive atomisation. The following work presents a numerical analysis of some impinging jets with relatively high Reynolds numbers. Two different nozzle diameters were considered, which were designed for fuels with different calorific values and stoichiometric ratios. The work aims to investigate the influence of the nozzle diameters on the liquid jets’ interaction
Kazmierski, BartoszKapusta, Łukasz Jan
The primary objective of any test program is to maximize the probability, within programmatic constraints, that the flight design will function properly and successfully when used in actual service for the intended application. Flight risks are mitigated via prudent and effective analysis and testing. While analysis can sometimes be used in place of test, proper analytical techniques utilize test data as the basis for model correlations. The combination of analysis and test verification is used for both qualification of the LRE design as well as workmanship verification of each LRE flight unit
Loose particles inside the additional pipe of a rocket engine are an important factor that causes propulsion system failure. For loose particles inside the additional pipe, it is necessary not only to determine whether they exist or not, but also to locate them for subsequent processing. Due to the complex structure of the additional pipe, the uneven medium used for sound wave transmission, and the anisotropic speed of the sound. Thus, it is difficult to determine the locations of loose particles by using the traditional time difference localization method. Aiming at this problem, this article proposed a localization method of loose particles based on Chaos Theory and Particle Swarm Optimization-Back-Propagation Neural Network (PSO BP Neural Network). First, chaotic characteristics of collision signals generated by loose particles are studied. On this basis, the localization method of loose particles based on PSO BP Neural Network is proposed, which uses the correlation dimension
Sun, ZhigangWang, GuotaoGao, MengmengGao, YajieGuo, Liang
This recommended practice is intended as a guide for the specification of electrohydraulic mechanical feedback servoactuators used for position control. It provides performance definitions and capabilities that are specific to mechanical-feedback servoactuators and different from those applicable to electrical-feedback servoactuators
A-6B1 Hydraulic Servo Actuation Committee
Researchers have used the ancient Japanese art of paper folding to possibly solve a key challenge for outer space travel: how to store and move fuel to rocket engines. They developed an origami-inspired, folded plastic fuel bladder that doesn’t crack at super-cold temperatures and could someday be used to store and pump fuel
NASA Glenn researchers developed a new oxide dispersion strengthened medium entropy alloy (ODS-MEA) via additive manufacturing (AM). ODS alloys, in which nanoscale ceramic particles are distributed within the metal, were originally developed to enhance mechanical properties (e.g., creep resistance, tensile strength, microstructure integrity) at extreme temperatures. Such alloys show promise for metal components of gas turbines, rocket engines, nuclear reactors, and other high-temperature applications; however, the conventional mechanical alloying process to produce such alloys is highly inefficient, time-consuming, and costly
Researchers have developed a rocket propulsion system, known as a rotating detonation rocket engine, that will allow upper stage rockets for space missions to become lighter, travel farther, and burn more cleanly
Founded on July 1, 1960, Marshall Space Flight Center in Huntsville, AL is one of NASA’s largest field centers. Marshall engineers designed, built, tested, and helped launch the Saturn V rocket that carried Apollo astronauts to the Moon. Marshall developed new rocket engines and tanks for the fleet of space shuttles, built sections of the International Space Station (ISS), and now manages all the science work of the astronauts aboard the ISS from a 24/7 Payload Operations Integration Center. Marshall also manages NASA’s Michoud Assembly Facility in New Orleans — the agency’s premier site for the manufacture and assembly of large-scale space structures and systems
Rocket engine testing requires a lot of light since all tests are filmed with high-speed cameras to monitor performance; however, those cameras have to adjust to the bright plume from a firing engine, which would black out the rest of the image. Traditionally, that light has been provided by metal halide bulbs
NASA Johnson Space Center developed reprogrammable and interchangeable electronic controllers that can attach to a system or subsystem wirelessly or through plug-and-play capability. Originally designed to work with rocket engines, this technology can control different systems and subsystems. This smart controller recognizes which system it is communicating with once connected to the network and loads the appropriate application to perform the required function in the system. The device enables a common set of spares and can talk to other devices of its kind by relaying information and instructions to other controllers. A prototype can be easily developed using low-cost solutions such as Raspberry Pi to demonstrate functionality
NASA’s Marshall Space Flight Center is building a small CubeSat that uses an 85-m2 solar sail deployed from a central location to capture the push of photons from the Sun as its propulsion source. To integrate this sail into the CubeSat, NASA inventors have developed a new method for folding and packaging the thin membrane
This Report presents general information on over 50 alloys in which nickel either predominates or is a significant alloying element. It covers primarily wrought materials, and is not necessarily all inclusive. Values given are in most cases average or nominal, and if more precise values are required the producer(s) should be contacted. This report does not cover the so-called "superalloys," or the iron base stainless steels. Refer to SAE J467, Special Purpose Alloys, and SAE J405, Chemical Compositions of SAE Wrought Stainless Steels, respectively, for data on these alloys
Metals Technical Committee
An orifice element is commonly used in liquid rocket engine test facilities either as a flow metering device, a damper for acoustic resonance, or to provide a large reduction in pressure over a very small distance in the piping system. The orifice as a device is largely effective in stepping down pressure; however, it is also susceptible to a wake-vortex instability that generates pressure fluctuations that propagate downstream and interact with other elements of the test facility, resulting in structural vibrations. Exacerbating the situation in cryogenic test facilities is the possibility of the formation of vapor clouds when the pressure in the wake falls below the vapor pressure, leading to cavitation. Cavitation has the potential for highamplitude fluctuations that can cause catastrophic damage to a facility
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