Browse Topic: Scramjet engines

Items (30)

Hypersonic Bi directional Blended Wing Body UAV Conceptual Development.

2022-26-113705/26/2022

This paper looks to develop a conceptual Hypersonic Bi-directional BWB UAV for high efficiency hypersonic systems.This concept successfully allows for many technical challenges involved in supersonic flight which are also present in hypersonic flight to be overcome; however some of these challenges become even greater, in addition to the new phenomena present at hypersonic speeds.The bi-directional BWB UAV concept consists of a symmetric planform which enables flight to occur at two different geometric configurations. The subsonic configuration would have a high aspect ratio and a low sweep and in the hypersonic configuration the UAV would then rotate 90 degrees which would have a low aspect ratio and high sweep. This design overcomes the inherent conflict between subsonic and hypersonic flight in conventional hypersonic launch systems.The airfoil of the subsonic configuration is thicker than that for the hypersonic configuration, a thick airfoil is needed to achieve a high lift

Fernandes, Shane

Autonomous Vehicle Engineering: May 2019

19AVEP0505/02/2019

Editorial AVs, data and 'surveillance capitalism' SAE AV Activities SAE launches Office of Automation The Navigator Lessons from the 737 Max-8 debacle Scorecard Waymo, GM and Ford pegged as autonomous leaders Designs to Dye for: Autonomy's New-Materials Revolution From pineapples to bacteria, Envisage's research is focused on new-mobility's 'inside' story. Dining on Data Processing, in real-time, the enormous data stream that's flowing through AVs is increasingly the job of NVIDIA's mighty GPUs. Danny Shapiro relishes the feast. New Performance Metrics for Lidar Frame-rate measurement is so yesterday. Object-revisit rate and instantaneous resolution are more relevant metrics, and indicative of what a lidar system can and should do, argues a revolutionary in the artificial-perception space. 5G Cellular May Be Transformational for Automakers, Suppliers Long-awaited 5G cellular technology will be a foundational base for expanding vehicle connectivity and autonomy, enabling far more data

Beam Shaping for CARS Measurements in Turbulent Environments

TBMG-2350012/01/2015

Taking measurements in a scramjet engine is particularly challenging because of the harsh testing environment. Any probe inserted in the flow would generate shock waves, strongly perturbing the flow. Coherent Anti-Stokes Raman spectroscopy (CARS) is a non-intrusive laser-based measurement technique that has been implemented successfully to measure temperature and species concentrations in ducted scramjet engines.

Dual-Cavity Rayleigh Scattering Measurement System

TBMG-2180804/01/2015

Molecular-based optical diagnostics techniques capable of obtaining simultaneous measurements of multiple fluid properties are critically important for characterizing hypersonic air-breathing engines, such as scramjet engines and scramjet-rocket combined cycle engines. Correlations between those properties lead to a more detailed understanding of complex flow behavior, and aid in the development of multiparameter turbulence models required for supersonic combustion engine flow path predictions.

An Ultimate Engine: designed by Computational Fluid Dynamics

2011-01-202708/30/2011

A single lightweight engine capable of operating over a wide range of Mach numbers from startup to the hypersonic regime is proposed for automobiles and airplanes. Traditional piston engines, turbojet engines, and scram jet engines operate only under a narrower range of conditions. A compression system of colliding super multijets is proposed instead of a traditional turbofan. This ultimate engine system can be extended with a special piston system to achieve an improved fuel consumption rate, while maintaining a low noise level.

Naitoh, Ken, Emoto, Takehiro, Nakamura, Kazushi, Kainuma, Yuusuke

Diode Laser Sensor for Scramjet Inlets

TBMG-885112/01/2010

The supersonic combustion ramjet (scramjet) engine is one of the more promising high-speed flight propulsion technologies. One of the reasons for this is the simplicity of the engine design, having no moving parts and requiring no external ignition source, and the fact that scramjets do not need to provide their own oxidizer. Despite this simplicity, several obstacles to the use of scramjet propulsion systems have become apparent, including the ability to produce sufficient fuel-air mixing at high speed, large total pressure losses, reduction in specific impulse with increasing flight Mach number, and the sensitivity of combustion to inlet temperature. This last problem can be very significant.

Measuring Skin Friction in Complex Flows That Include Shocks

TBMG-475412/01/2007

A methodology for measuring skin friction (also known as wall shear) in complex flows typical of those inside supersonic-combustion ramjet (scramjet) engines has been developed. The flows inside scramjet engines are turbulent and include shocks. Because the dynamic pressures of such flows are high, even small skin-friction coefficients can significantly degrade engine performance. Hence, it is desirable to measure skin friction in order to gain better understanding of engine performance and to enable calibration of skin-friction submodels of computational fluid dynamics models used to design scramjet engines. The presence of shocks and the large heat fluxes associated with flows in scramjet engines add to the challenge of measuring skin friction, and the present methodology provides means to meet the challenge. Major elements of the methodology are a generic design for a gauge and techniques for processing the readings of the gauge such that the wall shear at the gauge location can be

System for Imaging Turbulent Combustion Flows

TBMG-TB-00471110/01/2007

Flow regimes inaccessible to prior instrumentation can now be studied. The Components of the System enable diverse types of imaging, acquisition of image data, and processing of the data to extract information on multiple aspects of high-speed combustion flows. Asystem of scientific instrumentation and data-processing equipment has been assembled for research and education in turbulence, mixing, and chemical reactions (especially combustion) in high-speed laminar and turbulent flows. The system is designed to enable study of temporally varying, three- dimensional structures in flow regimes that have been inaccessible to prior instrumentation systems, with emphasis on flow regimes relevant to the operation of ramjet and scramjet engines.

Real-Time Simulation of Aeroheating the Hyper-X Airplane

TBMG-16801/01/2005

A capability for real-time computational simulation of aeroheating has been developed in support of the Hyper-X program, which is directed toward demonstrating the feasibility of operating an air-breathing ramjet/scramjet engine at mach 5, mach 7, and mach 10. The simulation software will serve as a valuable design tool for initial trajectory studies in which aerodynamic heating is expected to exert a major influence in the design of the Hyper-X airplane; this tool will aid in the selection of materials, sizing of structural skin thicknesses, and selection of components of a thermal-protection system (TPS) for structures that must be insulated against aeroheating.

Thermal Challenges of Mars Exploration

98168607/13/1998

The exploration of Mars is a major thrust of NASA. Some of the important goals of this exploration are the search for life; understanding the planet's evolution by in-situ and remote scientific measurements; developing an inventory of useful resources, including accessible water; and sample return as a precursor to human exploration. One of the key challenges of Mars's exploration hard-ware--- rovers, landers, probes, and science instruments -- is to be able to survive the planet's harsh environment on and below surface. This paper discusses the thermal challenges posed by relatively large temperature variations, analyses and experimental work done at JPL to address these challenges.

Manvi, Ram

Integrated Air Separation and Propulsion System for Aerospace Plane with Atmospheric Oxygen Collection

92097404/01/1992

Aerospace plane with atmospheric oxygen collection for oxidizer supplying on rocket part of trajectory is very attractive concept. The key unit of power plant of such plane is an air liquefaction and separation system. It is proposed to accomplish the oxygen extraction on the bank of vortex tubes of special kind. The compressor of low speed turbojet engine would served in oxygen collection phase of flight as pressure generator for air separation system. Poor air after oxygen extraction is supposed to use actively in one of power plant combustion chambers. The configuration of integrated air separation and propulsion system and results of estimation of system using on two stage aerospace plane are discussed.

Balepin, V.V., Tjurikov, E.V.

Aerospace Plane Hydrogen Scramjet Boosting

91207109/01/1991

The results of computational investigations carried out to clarify the possibilities of hydrogen scramjet thrust uprating in hypersonic flight (M >8) by adding to the fuel substances with higher density are presented. Thrust, specific impulse and density impulse are calculated while adding nitrogen, oxygen, water or inert liquated gases. Fuel is injected tangentially to air flow into combustion chamber with high velocity through gas generator nozzles. For scramjet boosting in hypersonic flight it is suggested to add oxygen to stoichiometric part of hydrogen instead of excessive part of hydrogen.

Rudakov, A.S., Krjutchenko, V.V., Lanshin, A.I.

Shock Interaction Induced by Two Hemisphere-Cylinders

91204309/01/1991

When shock impinges on the bow shock ahead of a blunt body, the shock-shock interaction occurs. Such interactions are classified into six patterns by Edney. In the present research we selected an interaction referred to as Type IV, where the impinging shock was generated by another blunt body. It is well known that pressure and heat transfer are greatly increased at the impinging point. We measured the pressure distributions along the body surface where shock impinges. Then, we performed numerical simulations to investigate the heat transfer rate and the interaction pattern, though it is two-dimensional for simplicity. We employed the FVS, Flux Vector Splitting, method to solve the Navier-Stokes equations. From the numerical simulations, the clear interaction pattern was obtained and it was found that this pattern is an unstable phenomenon.

Nagashima, Tetsuya, Nakamura, Yoshiaki, Yasuhara, Michiru, Tsuboi, Kiyoshi

Propulsion Systems with Air Precooling for Aerospaceplane

91118204/01/1991

Using LH2 heat sink capacity for air precooling in turbojets allows to increase specific impulse and in many cases to reduce specific mass (mass-to-sea level thrust ratio). A number of precooled turbojet schemes are considered. Classification of turbojet according to the cooled air amount and depth of cooling is proposed. ATR with extended precooling (Tout=100K) is examined in more detail. For propulsion systems including different types of engines, running simultaneously the concept of LH2 heat sink capacity concentration for turbojet air precooling is proposed.

Rudakov, A.S., Balepin, V.V.

Additional Fuel Component Application for Hydrogen Scramjet Boosting

90099004/01/1990

The results of computational investigations carried out to clarify the possibilities of hydrogen scramjet thrust uprating in hypersonic flight (Mf>8) by adding to the fuel substances with higher density are presented. Thrust, specific impulse and density impulse are calculated while adding nitrogen, oxygen, water or inert liquated gases. For scramjet boosting in hypersonic flight it is suggested to add oxygen or a heavy inert gas to stoichiometric part of hydrogen instead of excessive part of hydrogen.

Rudakov, A. S., Krjutchenko, V. V.

NUMERICAL SIMULATION OF FLOW THROUGH THE LANGLEY PARAMETRIC SCRAMJET ENGINE

89231409/01/1989

The numerical simulation of a three-dimensional turbulent, reacting flow through the entire Langley parametric scramjet engine has been obtained using a piecewise elliptic approach. The last section in the combustor has been analyzed using a parabolized Navier-Stokes code. The facility nozzle flow was analyzed as a first step. The outflow conditions from the nozzle were chosen as the inflow conditions of the scramjet inlet. The nozzle and the inlet simulation were accomplished by solving the three-dimensional Navier-Stokes equations with a perfect gas assumption. The inlet solution downstream of the scramjet throat was used to provide inflow conditions for the combustor region. The first two regions of the combustor were analyzed using the MacCormack's explicit scheme. However, the source terms in the species equations were solved implicitly. The finite rate chemistry was modeled using the two-step reaction model of Rogers and Chinitz. A complete reaction model was used in the PNS code

Srinivasant, Shivakumar, McClinton, Charles R., Kamath, Pradeep S.

Ramjet Propulsion for Single-Stage-to-Orbit Vehicles

77101102/01/1977

Several ramjet propulsion systems are evaluated for future Earth-to-orbit transportation designed for reduced operational cost, reduced loads on payloads, and increased flexibility of launch site and schedule. Fan ramjet engines are found to deliver reasonable payloads to orbit. Supersonic combustion ramjet engines are found to be desirable if engine mass can be minimized.

Martin, James A.

PNEUMATIC vs. MECHANICAL POWER EXTRACTION FOR AIRCRAFT ACCESSORIES

56026601/01/1956

McMANUS, RICHARD L.

A New Approach to Turbojet and Ramjet Engine Control

56004201/01/1956

THE role of pneumatics as a computing medium for engine control in high-speed flight is indicated, and use of pressure ratio as the logical pneumatic control parameter is discussed. The Microjet concept of pressure ratio control, operating without springs and evacuated references, is introduced and compared to conventional means. This principle is expanded to demonstrate various computing and function-generating operations with respect to theoretical and practical design criteria. Typical present and projected applications to the control of turbojet and ramjet engine cycles are illustrated. This paper received the SAE Wright Brothers Medal for 1955.

Reed, Wendell E.

TURBOJET ENGINES FOR PILOTLESS AIRCRAFT, PRESENT AND FUTURE

55007801/01/1955

ROGERS, JOHN D.

ON THE LOCATION OF HELIPORTS: OPERATING AND OTHER PROBLEMS IN THE SELECTION OF SUITABLE SITES

55006301/01/1955

BROCK, HORACE

THE AERODYNAMIC AND POWER PLANT HEATING PROBLEM IN HIGH SPEED AIRCRAFT

54027701/01/1954

KINSLER, M. R.

SIMULATED FLIGHT FOR ENGINES AT AEDC

53007401/01/1953

NEWTON, G. W.

THE SELECTION AND EVALUATION OF POWERPLANTS FOR HELICOPTERS

53003301/01/1953

KATZENBERGER, E. F., NOZICK, H. J.

NACA'S ROLE IN GUIDED MISSILE RESEARCH

52014501/01/1952

Shortal, Joseph A.

ROCKET AND RAMJET SUPERSONIC POWERPLANTS

49012301/01/1949

WALKER, J. H.

AIRCRAFT POWER PLANT PROBLEMS

47011201/01/1947

CHENOWETH, OPIE

Resume of pulse jets, ram jets and rockets

47006101/01/1947

Lawrence, Lovell

PULSE JETS, RAM JETS AND ROCKETS

46009801/01/1946

Lawrence, Lovell

PAST, PRESENT AND FUTURE OF JET PROPULSION

45005701/01/1945

Chidlaw, Benjamin

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