Browse Topic: Thrust

Items (683)
The experimental investigation analyzed the performance of three machining conditions: dry machining, cryogenic machining, and cryogenic machining with minimum quantity lubrication (MQL) on tool wear, cutting forces, material removal rate, and microhardness. The outcome of this study presents valuable knowledge regarding optimizing conditions of turning operations for Ti6Al4V and understanding the machinability under cryogenic-based cooling strategies. Based on the experimentation, cryogenic machining with MQL is the most beneficial approach, as it reduces cutting force and flank wear with a required material removal rate. This strategy significantly enhances the machining efficiency and quality of Ti6Al4V under variable feed rates (0.05 mm/rev, 0.1 mm/rev, 0.15 mm/rev, 0.2 mm/rev, 0.25 mm/rev) where cutting velocity (120 m/min) and depth of cut (1 mm) are constant. The effects of the main cutting force, feed force, thrust force, material removal mechanism, flank wear, and
Misra, SutanuKumar, YogeshPaul, GoutamForouhandeh, Fariborz
Electrohydrodynamic (EHD) technology, noted for its absence of moving mechanical parts and silent operation, has attracted significant interest in plane propulsion. However, its low thrust and efficiency remain key challenges hindering broader adoption. This study investigates methods to enhance the propulsion and efficiency of EHD systems, by examining the electrohydrodynamic flow within a wire-cylinder corona structure through both experimental and numerical approaches. A multi-wire-cylinder positive corona discharge experimental platform was established using 3D printing technology, and measurements of flow velocity, voltage, and current at the cathode outlet were conducted. A two-dimensional simulation model for multi-wire-cylinder positive corona discharge was developed using Navier-Stokes equations and FLUENT user-defined functions (UDF), with the simulation results validated against experimental data. The analysis focused on the effects of varying anode diameters and the
Huang, GuozhaoDong, GuangyuZhou, Yanxiong
There are examples in aerodynamics that take advantage of electric-to-aerodynamic analogies, like the law of Biot–Savart, which is used in aerodynamic theory to calculate the velocity induced by a vortex line. This article introduces an electric-to-aerodynamic analogy that models the lift, drag, and thrust of an airplane, a helicopter, a propeller, and a flapping bird. This model is intended to complement the recently published aerodynamic equation of state for lift, drag, and thrust of an engineered or a biological flyer by means of an analogy between this equation and Ohm’s law. This model, as well as the aerodynamic equation of state, are both intended to include the familiar and time-proven parameters of pressure, work, and energy, analytical tools that are ubiquitous in all fields of science but absent in an aerodynamicists’ day-to-day tasks. Illustrated by various examples, this modeling approach, as treated in this article, is limited to subsonic flight.
Burgers, Phillip
Design of Launch vehicle is multidisciplinary process in which designers of all the domain of engineering like mechanical, electronics, chemical, materials etc contribute. For the mechanical design, Coupled Load Analysis (CLA) is statutory requirement without which no launch vehicle will be allowed to fly. In CLA, launch vehicle is subjected to various loads during its flight due to engine thrust depletion / shut-off, thrust oscillation, wind and gust, maneuvering loads. In aerospace industry a standard CLA is performed by generating the mathematical model of launch vehicle and coupling it with reduced mathematical model of payload and applying the boundary conditions. A CLA is a time consuming process as several flight instances and load cases need to be considered along with generation of structural dynamic model at each time instants. For every new mission, the payloads are mission specific whereas the launch vehicle and the loads remain unchanged. To take advantage of this fact, a
Kurudimath, KottreshJalan, Salil KanjRose, Jancy
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
Heavy Commercial Road Vehicles (HCRVs) may be more susceptible to rollover incidents due to their higher centre of gravity position than passenger vehicles, and rollover is one of the significant causes of HCRV accidents. Therefore, variation in vehicle roll behaviour becomes crucial to the safety of an HCRV. Toe misalignment is a commonly observed phenomenon in HCRVs, and studying its impact on roll behaviour is important. In this study, the impact of the symmetric toe and thrust misalignment on the roll behaviour of an HCRV is analysed using IPG TruckMaker®, a vehicle dynamics simulation software. A ramp steer manoeuvre was used for the simulations, and the toe misalignment on a wheel was chosen from the range [-0.21°, 0.21°]. Variation in roll behaviour was quantified using the steering wheel angle at which one-wheel lift-off (OWL) occurred (SWAL). Additionally, an analytical model was formulated to predict OWL and the model predictions were compared with the results from IPG
Chandran, AmarchandGrandhe, RoshanMukhopadhyay, ArkoSharma, MitanshuShankar Ram, C S
The requirement of the current scenario is to identify the sustainable material and process it into acceptable properties for current applications. The natural fiber is a prime sustainable material having the properties of biodegradability, plenty of availability, economical and adequate physical-mechanical property. Sesbania rostrata fiber is extracted from the stem of Sesbania rostrata plant which is cultivated along with Turmeric plants on 1000 acres annually as a nitrogen fixation plant. The fiber-reinforced composite is a tailor made material by altering the fiber and polymer weight proportion to achieve desired properties for applications. The natural fiber is a promising material to replace synthetic fiber to transform the composite into biodegradable. The making of holes in the biocomposite by the secondary process is essential for the assembly operation. The biocomposite was developed by reinforced Sesbania rostrata fiber in Polycaprolactone (PCL) biopolymer at the weight
Raja, KA, KarthikSenthil Kumar, MSP S, Sampath
Thrust measurement systems come in many sizes and shapes, with varying degrees of complexity, accuracy and cost . For the purposes of this information report, the discussions of thrust measurement will be limited to axial thrust in single-axis test systems.
EG-1E Gas Turbine Test Facilities and Equipment
In an application first, the physics of why the sky is blue is used to measure gas flows without obstructive sensors. A longstanding industry partnership between Virginia Polytechnic Institute and State University (Virginia Tech) and Pratt & Whitney has resulted in a new laser-optical technology that aims to revolutionize in-flight thrust measurement.
In this research, the performance of two commercially available icephobic coatings is evaluated on an 81% scaled-down version of the Bell Flight APT 70 drone propeller. Tests are performed in an icing wind tunnel (IWT) under selected severe icing conditions to test the ice protection capability of coatings against both glaze and rime ice. Two different coating formulations are used, one is a polydimethylsiloxane (PDMS) acetoxy terminated coating, the other an epoxy-silicone. The coatings were briefly characterized in terms of their surface roughness, water contact angle and ice adhesion reduction factor compared to aluminum using the centrifugal adhesion test (CAT). Blade sets were prepared for both coatings and a third uncoated set was tested for reference purposes. Tests in the IWT were performed to simulate a true airspeed of 35 m/s and a constant propeller rotational speed of 5 500 RPM. Two conditions of liquid water content (LWC) and droplet median volumetric diameter (MVD) were
Harvey, DerekVilleneuve, EricVolat, ChristopheBeland, MathieuLapalme, Maxime
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
The reactionless drive is an internal momentum engine which until recently has been deemed impossible under the laws of physics. In this paper, the authors will extend the equation for reaction less propulsion = F=−μq2/6πcmr2v×dBdt+B×dvdt and derive an additional equation, which we call “The Sektet Equation” governing the system of motion, FSek=−μq2/6πcmr2∗2B∗dBdt. The results of the paper show that significant thrusts can be generated on relatively low voltages and energy inputs. It applies this equation to explain how NASA’s EM drive likely produces thrust via the “Sektet Equation” using a three circuit analysis of the Sektet Force.
Chen, EdCronin, Tara
This method covers electric outboards that are rated in terms of static thrust.
Marine Technical Steering Committee
In-space and planetary surface assembly for human exploration is a challenging domain that encompasses various technological thrusts to support human missions. NASA is developing autonomous assembly agents to build structures like habitats and antennae on the Moon. These modular and reconfigurable Assembler robots will provide robotic assembly of structures, even in locations that prohibit constant human oversight and teleoperation.
Researchers at NASA’s Jet Propulsion Laboratory (JPL) are developing a novel microthruster that could provide easy-to-control propulsion during spaceflight. Using solid silver as the fuel source, this innovative microthruster provides thrust via electrospray without heating the fuel reservoir or transporting liquid metals. Instead of transporting a molten metal, this design transports metal ions via a solid electrolyte film.
The electric propulsion system plays an important role during the operation of a satellite, i.e., maintaining the position of the north-south poles, adjusting the attitude, and transferring the orbit, where vector adjustment device is a key part of the system. We developed a new large-angle device to transfer thruster orbital, which has three driving motors and the failure of a single motor cannot affect the operation. The posture angle and linear pair displacement of this mechanism are simulated using forward and inverse kinematics solutions. In the following, the actual adjustment angle was measured with a three-coordinates measuring instrument and a gradiometer to compare with the simulated values. This design has been successfully applied in China’s asteroid exploration mission.
Lu, DengbaiLiu, MingmingCui, XiaojieGuo, MeiruRen, ZhengyiYang, Zhe
IVO Ltd. Bismark, ND +1 701-390-9567
Slowed rotors – traditionally associated with autogyros and gyroplanes – have long been recognized as one potential solution for high-speed helicopters (200-300 knots). During the 1950s–70s, there were several significant programs that led to the development of high-speed helicopters with thrust and lift compounding. The key technology barriers common to all were extremely high fuel consumption due to high advancing side drag and large reverse flow, complexities associated with RPM reduction, large blade motions during RPM reduction, and unexplained but catastrophic aeroelastic instabilities of rigid rotors (Cheyenne). None of these helicopters entered regular production.
This paper describes the implementation, integration, testing and performance evaluation of compact and battery-less alternator with external regulator for diesel engine for avionics application. The key responsibility of this alternator is to generate 2.8kW power with 28V regulated power supply for various loads. The alternator has been integrated and installed on the diesel engine and further tested on dynamometer and thrust cradle with propeller combination. The alternator when used in conjunction with ACU (Alternator Control Unit) that is designed to boot strap field voltage during low speed operation, has the ability to self-excite. The alternator / ACU system has the ability to generate power even in the absence of battery voltage i.e. in battery less systems or those in which the battery is not always connected to the alternator. External voltage regulator has been used which minimizes ripple up to 1.0V. The alternator rpm ranges from 3000 to 10000 for generating maximum power
TRIPATHI, S KRadhakrishna, DPatel, T S
Passengers would always like to reach their destinations with minimum commute time. Generating a higher thrust is a necessity. This implies that the turbomachinery associated with the power plant has to rotate faster and with higher efficiencies. However, high rotational speeds, mainly in the transonic regime, often lead to boundary layer separation, shocks, compressor stall, and surge. The current investigation is an attempt to reduce the abovementioned phenomena. It involves the performance study of a smoothened controlled diffusion airfoil (CDA) blade that has been optimized by “Multi-Objective Genetic Algorithm” (MOGA) by altering maximum camber location and stagger angle. Inlet pressure is varied from 15 kPa to 30 kPa and the angle of attack ranging from 40.4° to 56.4°. C48-S16-BS1 is validated and considered as the baseline profile, and all other blades are collated to this. It is observed that shifting the location of the maximum camber close to the leading edge and increasing
Vishwajeeth, A.Badr, Syeda RoquiyaCherian, Nevin C.Ponangi, Babu RaoRavichandran, K.S.
Reduction gears are very commonly used in the automotive and aviation industries. A propeller’s efficiency decreases rapidly as the speed of the blade tips nears the speed of sound. An engine reduction gear enables the engine to develop more torque while reducing the propeller’s revolutions per minute (RPM). This prevents the propeller’s efficiency from decreasing. This work deals with a detailed methodology for the design and analysis of a single-stage reduction gear. Custom pinion and wheel were modelled along with the engine assembly. A custom mount was designed and fabricated to allow for engine-reduction gear system integration. In this work, a 7.5 cubic centimeter (cc) single-cylinder glow engine is used. Bending and contact stress analysis was performed, and the results were compared with the calculated stress values. The torque demands were analyzed for propellers of different sizes at varying aircraft speeds. Quantitative analysis of thrust is also carried out before and after
Maulik, Shomi DeepKurdekar, ChinmayGoenka, Rahul RakeshThomas, Benedict
From the fact that a propulsor consumes less power for a given thrust if the inlet air is slower, simulations are conducted for a propulsor imposed behind an airfoil as ideal boundary layer ingestion (BLI) propulsor to stand on the benefits of this configuration from the point of view of power and efficiency and to get a closer look on the mutual interaction between them. This interaction is quantified by the impact on three main sets of parameters, namely, power consumption, boundary layer properties, and airfoil performance. The position and size of the propulsor have great influence on the flow around the airfoil. Parametric studies are carried out to understand their influence. BLI propulsor directly affects the power saving and all of the pressure-dependent parameters, including lift and drag. For the present case, power saving reached 14.4% compared to the propeller working in freestream.
El-Salamony, Mostafa E.Teperin, Leonid L.
Vertical takeoff and landing vehicle platforms with many small rotors are gaining importance for small UAVs as well as distributed electric propulsion for larger vehicles. To predict vehicle performance, it must be possible to gauge interaction effects. These rotors operate in the less-known regime of low Reynolds number, with different blade geometry. As a first step, two identical commercial UAV rotors from a flight test program are studied in isolation, experimentally and computationally. Load measurements were performed in Georgia Tech’s 2.13 m × 2.74 m wind tunnel. Simulations were done using the RotCFD solver which uses a Navier-Stokes wake computation along with rotor-disc loads calculation using low-Reynolds number blade section data. It is found that in hover, small rotors available in the market vary noticeably in performance at low rotor speeds, the data converging at higher RPM and Reynolds number. This is indicative of the high sensitivity of low-Re rotor flows to minor
Tomar, YashvardhanShukla, DhwanilKomerath, Narayanan
Icing is a major hazard for aviation safety. Over the last decades an additional risk has been identified when flying in clouds with high concentrations of ice-crystals where ice accretion may occur on warm parts of the engine core, resulting in engine incidents such as loss of engine thrust, strong vibrations, blade damage, or even the inability to restart engines. Performing physical engine tests in icing wind tunnels is extremely challenging, therefore, the need for numerical simulation tools able to accurately predict ICI (Ice Crystal Icing) is urgent and paramount for the aeronautics industry, especially regarding the development of new generation engines (UHBR = Ultra High Bypass Ratio, CROR = Counter rotating Open Rotor, ATP = Advanced Turboprop) for which analysis methods largely based on previous engines experience may be less and less applicable. The European research project MUSIC-haic has been conceived to fill this gap and has started in September 2018. MUSIC-haic brings
Villedieu, PhilippeTrontin, PierreAouizerate, GillesBansmer, StephanVanacore, PaoloRoisman, IliaTropea, Cameron
A 3D CFD methodology is presented to simulate ice build-up on propeller blades exposed to known icing conditions in flight, with automatic blade pitch variation at constant RPM to maintain the desired thrust. One blade of a six-blade propeller and a 70-passenger twin-engine turboprop are analyzed as stand-alone components in a multi-shot quasi-steady icing simulation. The thrust that must be generated by the propellers is obtained from the drag computed on the aircraft. The flight conditions are typical for a 70-passenger twin-engine turboprop in a holding pattern in Appendix C icing conditions: 190 kts at an altitude of 6,000 ft. The rotation rate remains constant at 850 rpm, a typical operating condition for this flight envelope. Two icing conditions are simulated: air static temperature -23 °C, LWC 0.2 g/m3 and MVD 20 microns resulting in rime ice, and air static temperature -16 °C, LWC 0.3 g/m3 and MVD 20 microns resulting in mixed ice with rime to glaze transition in the radial
Ozcer, IsikBaruzzi, Guido S.Desai, MirajYassin, Maged
This standard establishes the basic triangular profile for the MJB thread form, the design profiles, standard pitches, tolerance classes, formulae for tolerances and dimensions, tolerance tables, and a system of designations. Because of the specialized application for buttress threads, no preferred diameter-pitch series have been established for this standard and each application will require use of the thread formulae for dimensions and related tolerances given herein for deriving the thread dimensional requirements.
E-25 General Standards for Aerospace and Propulsion Systems
This SAE Aerospace Information Report (AIR) records the results of an investigation of a dual rotation propeller shaft standard for an engine supplied bearing and the reason for deciding that such a bearing is impracticable.
E-25 General Standards for Aerospace and Propulsion Systems
Bleeding in engines is essential to mitigate the unmatched air massflow between low and High Pressure (HP) compressors at low speed settings, thus avoiding unstable operation due to surge and phenomena. However, by emerging the More Electric Aircraft (MEA) the engine is equipped with electrical machines on both high and Low Pressure (LP) spools which enables transfer of power electrically from one spool to another and hence provides the opportunity to operate engine core components closer to their optimum design point at off-design conditions. At lower power setting of the engine, HPC speed can be increased by taking power from LP shaft and feeding it to HP shaft which can lead to the removal of the bleeding system which in turn reduces weight and fuel consumption and help to overcome engine instability issues. Fuel consumption can be decreased by decreasing inconsistent thrust with the aircraft mission for flight and ground idle settings. This paper investigates the idea of power
Balaghi Enalou, HosseinLe-Peuvedic, Jean-MarcRashed, MohamedBozhko, Serhiy
A highly miniaturized, MR-143, green monopropellant thruster was developed for 1N thrust. Testing indicated the initial catalyst bed heater was insufficient. In subsequent development, the thruster was equipped with a more efficient catalyst bed heater. For reliable ignition of the advanced, non-toxic, AF-M315E monopropellant, the catalyst needs to be preheated. This preheat temperature is much higher than what hydrazine thrusters require. Moreover, the combustion temperature of hydroxyl ammonium nitrate (HAN)-based monopropellants is higher than hydrazine, so the catalyst bed heater must be able to withstand repeated soak-back temperatures.
In this study, we focus on “camber angle control” and “derivative steering assistance” using “steer-by-wire” as maneuverability and stability improvement techniques that are appropriate for the electric vehicle (EV) era. Movements that produce a negative camber angle generate camber thrust, and vehicle motion performance improvements extend from the fact that the tire side force is increased by the camber thrust effect. In our experimental vehicle, a proportional steering angle system was used to create negative camber angle control via an electromagnetic actuator that allowed us to confirm improvements to both the effectiveness and stability of steering control in restricted cornering areas. More specifically, we determined that it is possible to improve critical cornering performance by executing ground negative camber angle control in proportion to the steering angle. Steer-by-wire refers to an electrical steering technique that allows the steering angle of the entire vehicle to be
Yamaguchi, RyoNozaki, Hiromichi
This SAE Aerospace Information Report (AIR) records the dimensions for the No. 70-90, 70L-90, 80-100, and 80L-100 dual rotation propeller shaft ends, which have been deleted from ARP375.
E-25 General Standards for Aerospace and Propulsion Systems
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