scholarly journals STUDY ON THE STATIC AND DYNAMIC STABILITY OF A MODULAR AIRPLANE SYSTEM

Aviation ◽  
2016 ◽  
Vol 20 (4) ◽  
pp. 160-167 ◽  
Author(s):  
Agnieszka KWIEK
Keyword(s):  
Dynamic Stability ◽  
Static Stability ◽  
Space Technology ◽  
Space Flights ◽  
Space Tourism ◽  
Longitudinal Dynamic ◽  
Static And Dynamic Stability ◽  
Control Derivatives ◽  
Point To Point ◽  
The Stability

The purpose of this research is an analysis of the static and dynamic stability of the Modular Airplane System (MAS). The MAS is designed to perform suborbital space flights. The concept assumes that two tailless vehicles bonded together form a conventional aircraft where the wing of the second one is used as the horizontal tail of the whole system. The CFD calculations, and the stability and control derivatives were conducted by the PANUKL package, which uses a low order panel method for the aerodynamic analysis. The analysis of the static and dynamic stability was performed by the SDSA package. Only the selected part of the MAS mission was investigated. The results that will be presented have been divided into three parts: static stability, longitudinal dynamic stability and lateral dynamic stability. The MAS has a few possible applications. The first one is a suborbital space tourism flight. Moreover, it can be used as a lunching vehicle for micro satellites or as a testing platform for new space technology to improve their TRL level. Finally, in the far future, it could be used as a fast point-to-point travel system. The paper presents the results of the static and dynamic stability of a unique aircraft configuration which consists of two tailless vehicles. The research focuses on a situation where the vehicles are just before separation and their mass is similar. Moreover, the influence of the second vehicle’s position with respect to the first one is included.

An Analysis of the Static and Dynamic Stability of an Hypersonic Transport Aircraft Longitudinal Motion Flying at Hypersonic Speeds and Various Heights

2012 ◽  
Author(s):  
D. Mclean ◽  
Z.A. Zaludin ◽  
P.R. Arora
Keyword(s):  
Mathematical Model ◽  
Dynamic Stability ◽  
Static Stability ◽  
Longitudinal Motion ◽  
Transport Aircraft ◽  
Static And Dynamic Stability ◽  
Hypersonic Speeds ◽  
Scramjet Engine ◽  
The Stability ◽  
Engine Condition

Suatu kajian tentang kestabilan statik dan dinamik pesawat pengangkutan hipersonik hipotesis telah dilakukan dengan menggunakan model matematik untuk pergerakan membujur semasa penerbangan di keadaan penerbangan yang berlainan. Hasil daripada analisis kestabilan menunjukkan bahawa pesawat tersebut akan menjadi lebih tidak stabil apabila penerbangan di nombor Mach dan ketinggian yang lebih tinggi daripada keadaan penerbangan nominal. Juga disertakan di sini keadaan enjin scramjet apabila pesawat ini terbang pada kelajuan hipersonik dan ketinggian yang berlainan. Kata kunci: dinamik pesawat; kestabilan dinamik; kestabilan statik; enjin scramjet A study of the static and dynamic stability of an hypothetical hypersonic transport aircraft was conducted based on a mathematical model of the longitudinal motion of the aircraft flying at a number of different flight conditions. The result from the stability analysis has shown that the aircraft becomes even less stable at higher Mach numbers and heights than the nominal flight condition. Also discussed here is the scramjet engine condition when the aircraft was simulated to be flying at hypersonic speeds and different heights. Key words: aircraft dynamics; dynamic stability; static stability; scramjet engine

Static and Dynamic Handling Stability of Server Rack Computers

2014 ◽  
Author(s):  
Budy D. Notohardjono ◽  
Robert Sanders
Keyword(s):  
Finite Element ◽  
Stability Analysis ◽  
Finite Element Modeling ◽  
Dynamic Stability ◽  
Mechanical Energy ◽  
Static Stability ◽  
Element Modeling ◽  
Static And Dynamic Stability ◽  
Maximum Angle ◽  
Mechanical Handling

This paper discusses the static and dynamic stability analysis of rack or frame computer/server products during shipping and relocation. The static stability is the ability of server products to resist tipping over on a typical raised floor in a datacenter or when it is installed in its operational product environment. The dynamic stability is the ability to resist tipping over when a velocity change occurs during re-location either on flat or inclined planes. The product consists of a frame or a rack in which components such as processor units, input-output units and power supplies are installed. The static stability analysis presented here calculates the tip over threshold angle, which is the maximum angle of an inclined plane on which the product can be placed without tipping over. The location of the installed components in a frame, the dimension and weight of the installed components, and the dimension of the product dictate the overall static stability of the product. Specifically, those parameters affect the location of the center of gravity of the product and the tip over threshold angle. The tip over threshold angle is a critical parameter influencing the dynamic stability of the product.. The dynamic stability of an unpackaged product moving on casters can be calculated using the conservation of mechanical energy principle. Finite element modeling is a good way to evaluate the dynamic stability of a product during manual handling or mechanical handling; for instance, on a forklift. The objective of the finite element modeling is to provide guidelines on the maximum speed, minimum radius curvature, and safe turning speed of a forklift when transporting a product. The main objective of the analysis presented here is to provide a method for analyzing the static and dynamic stability of a rack style computer server product during shipping, relocation, and handling.

scholarly journals Definition of the Layout for a New Facility to Test the Static and Dynamic Stability of Agricultural Vehicles Operating on Sloping Grounds

2019 ◽  
Vol 9 (19) ◽  
pp. 4135 ◽  
Author(s):  
Marco Bietresato ◽  
Fabrizio Mazzetto
Keyword(s):  
Dynamic Stability ◽  
Design Process ◽  
Degrees Of Freedom ◽  
Static Stability ◽  
Rotating Platform ◽  
Conceptual Approach ◽  
Advantages And Disadvantages ◽  
Static And Dynamic Stability ◽  
Definition Of ◽  
Static Conditions

In this study, a new rig for investigating the static and dynamic stability of agricultural machines was conceived: its architecture was studied and its layout was designed following a specific conceptual approach. The first part of the proposed design process specifically addresses the test equipment and follows a ‘top-down’ logic starting from the requisites of the tests to perform. This approach alternates analysis and synthesis phases and exploits two important principles of the creative design process: functional analysis and decomposition, and kinematic inversion. During this process, many solutions (kinematic mechanisms, actuators) were proposed and discussed based on their advantages and disadvantages towards the definition of an optimal configuration. Therefore, the layout of a new mechanical system has been developed, which is supposed to steer subsequent and more detailed design-phases appropriately. The proposed facility has many innovative features compared to traditional test systems, in which vehicles are tested for lateral overturning under static conditions with the steering components (wheels/central joint for conventional/articulated vehicles) usually in a configuration corresponding only to a straight-path trajectory. Indeed, the present test rig is a mechanical installation with three degrees of freedom. It presents a wide plane, which can be tilted, composed by two semi-platforms connected by a central articulation hinge, operated by hydraulic jacks which allow the different angulations of the semi-platforms. It is specifically thought for performing dynamic stability tests of vehicles, especially on circular trajectories. An additional subsystem embedded in one of the two semi-platforms, configured as a rotating platform (‘turntable’), can test the global (static) stability of motionless vehicles placed on it.

scholarly journals Studying self-starting of 0.4 kV induction motors of power plant auxiliary needs

2020 ◽  
Vol 24 (5) ◽  
pp. 1053-1068
Author(s):  
Abdullo Majidov ◽  
◽  
Keyword(s):  
Power Plant ◽  
Dynamic Stability ◽  
Power Plants ◽  
Induction Motors ◽  
Mutual Influence ◽  
Accurate Determination ◽  
Static Stability ◽  
The Self ◽  
Static And Dynamic Stability ◽  
Voltage Dips

The purpose of this work is to study the self-starting of induction motors for the auxiliary needs of power plants and substations as well as the mutual influence of motors on each other under short-term voltage dips and after voltage recovery on the buses to which these motors are connected. The object of the research is the operating VIII section with the capacity of 0.4 kV of the auxiliary service system with 9 induction motors of the heat and power plant no.1 in the city of Dushanbe (Republic of Tajikistan). Simulation modeling was carried out in the software package Electrical Transient Analyzer Program (USA) using algebraic and simplified differential equations to determine the values of indicators of static and dynamic stability of auxiliary needs of power plants and substations. As a result of modeling, the values of indicators of static and dynamic stability of the auxiliary needs system of power stations are determined. Based on the results obtained the margins of static and dynamic stability of auxiliary needs of power plants and substations are constructed and the conditions for implementing the optimal self-start, which allow to ensure uninterrupted operation of responsible mechanisms with induction motors at voltage dips are determined. The developed methods for studying the self-starting of power plant and substation auxiliary need induction motors ensures more accurate determination of the values of static stability voltages and dynamic stability time. The developed simulation model allows to specify and determine the success of induction motor self-starting in the systems of power plant and substation auxiliary needs. The developed methods are recommended for more precise selection of operating values for relay protection and automation as well as technological protection in the systems of auxiliary needs of power plants and substations with induction motors for more reliable operation of the main and auxiliary technological equipment.

scholarly journals Kajian tentang stabilitas KM. Surya Prima yang dibuat di Desa Borgo, Kec. Tanawangko, Kab. Minahasa

2015 ◽  
Vol 2 (1) ◽  
Author(s):  
Gerry Willardoe Kayadoe ◽  
Heffry V. Dien ◽  
Revols D.Ch. Pamikiran
Keyword(s):  
Dynamic Stability ◽  
Area Under The Curve ◽  
Static Stability ◽  
International Maritime Organization ◽  
Stability Calculation ◽  
Calculation Results ◽  
C 30 ◽  
The Stability ◽  
Parameter Values ◽  
The Village

ABSTRACT The stability of a ship is one of the important technical factors in supporting successful fishing operations, and ultimately improving the welfare of fishermen; therefore a study on the stability of KM. Surya Prima had been done in the village of Borgo, District of Tanawangko, Minahasa Regency. Dynamic stability is the stability of the vessel measured by giving a force at the boat to form a certain rocking angle. This stability is expressed as an area under the curve of static stability. Dynamic ship stability calculation results will be compared with the stability criteria according to the International Maritime Organization (IMO) as in Fyson (1985) through the GZ curve. From the comparison it will get the level of dynamic stability of the vessel under study. Dynamic stability parameter values of Surya Prima purse seine vessel were: A (0-300) = 0.1179 m-rad., B (0-400) = 0.1935 m-rad., C (30-400) = 0.07552 m-rad., D (Angle GZmax) = 48 097, E (GZmin) = 0.475 m, F (GM) = 0965 m. Keywords: stability, curve, purse seiner   ABSTRAK Kestabilan kapal adalah salah satu faktor teknis penting dalam menunjang sukses operasi penangkapan ikan, dan pada akhirnya akan membantu meningkatkan kesejahteraan nelayan; oleh karena itu telah diadakan penelitian stabilitas KM. Surya Prima di Desa Borgo, Kecamatan Tanawangko, Kabupaten Minahasa. Stabilitas dinamis adalah stabilitas kapal yang diukur dengan jalan memberikan suatu usaha pada kapal sehingga membentuk sudut oleng tertentu. Stabilitas dinamis dinyatakan dalam luas area di bawah kurva stabilitas statis. Hasil perhitungan stabilitas dinamis kapal yang diukur dibandingkan dengan nilai kriteria kestabilan kapal oleh International Maritime Organization (IMO) dalam Fyson (1985) melalui kurva GZ. Dari perbandingan itu akan didapatkan tingkat kestabilan dinamis dari kapal yang diteliti. Nilai parameter kestabilan dinamis kapal pukat cincin Surya Prima adalah sebagai berikut: A (0-300) = 0.1179 m-rad., B (0-400) = 0.1935 m-rad., C (30-400) = 0.07552 m-rad., D (Sudut GZmax) = 48.097, E (GZmin) = 0.475 m, F (GM) = 0.965 m. Kata-kata kunci: stabilitas, kurva, pukat cincin

Study of Static and Dynamic Stability of an Exponentially Tapered Circular Revolving Beam Exposed to a Variable Temperature Grade under Several Boundary Arrangements

2019 ◽  
Vol 24 (3) ◽  
pp. 504-510
Author(s):  
Rakesh Ranjan Chand Chand ◽  
Pravat Kumar Behera ◽  
Madhusmita Pradhan ◽  
Pusparaj Dash
Keyword(s):  
Dynamic Stability ◽  
Variable Temperature ◽  
Research Work ◽  
Equation Of Motion ◽  
Revolution Speed ◽  
Static And Dynamic Stability ◽  
End Conditions ◽  
Variation Parameter ◽  
Instability Regions ◽  
The Stability

This research work is concerned with the static and dynamic stability study of an exponentially tapered revolving beam having a circular cross-section exposed to an axial live excitation and a variable temperature grade. The stability is analysed for clamped-clamped, clamped-pinned, and pinned-pinned end arrangements. Hamilton’s principle is used to develop the equation of motion and accompanying end conditions. Then, the non-dimensional form of the equation of motion and the end conditions are found. Galerkin’s process is used to find a number of Hill’s equations from the non-dimensional equations. The parametric instability regions are acquired by means of the Saito-Otomi conditions. The consequences of the variation parameter, revolution speed, temperature grade, and hub radius on the instability regions are examined for both static and dynamic load case and represented by a number of plots. The legitimacy of the results is tested by plotting different graphs between displacement and time using the Runge-Kutta fourth-order method. The results divulge that the stability is increased by increasing the revolution speed; however, an increase in the variation parameter leads to destabilization in the system and for same parameters, the stability is less in the case of a variable temperature grade than that of a constant temperature grade condition.

Tip-Over Stability Analysis of Mobile Boom Cranes With Swinging Payloads

2013 ◽  
Vol 135 (3) ◽  
Author(s):  
Andreas Rauch ◽  
William Singhose ◽  
Daichi Fujioka ◽  
Taft Jones
Keyword(s):  
Stability Analysis ◽  
Dynamic Analysis ◽  
Dynamic Stability ◽  
Dynamic Method ◽  
Static Stability ◽  
Multibody Simulation ◽  
The World ◽  
The Stability ◽  
Boom Crane ◽  
Mobile Base

Mobile boom cranes are used throughout the world to perform important and dangerous manipulation tasks. The usefulness of these cranes is greatly improved if they can utilize their mobile base when they lift and transfer a payload. However, crane motion induces payload swing. The tip-over stability is degraded by the payload oscillations. This paper presents a process for conducting a stability analysis of such cranes. As a first step, a static stability analysis is conducted to provide basic insights into the effects of the payload weight and crane configuration. Then, a semi-dynamic method is used to account for payload swing. The results of a full-dynamic stability analysis using a multibody simulation of a boom crane are then compared to the outcomes of the simpler approaches. The comparison reveals that the simple semi-dynamic analysis provides good approximations for the tip-over stability properties. The results of the stability analyses are verified by experiments. The analysis in this paper provides useful guidance for the practical tip-over stability analysis of mobile boom cranes and motivates the need to control payload oscillation.

Analysis and Simulation of UAV Aircraft Flight Dynamics

2014 ◽  
Vol 915-916 ◽  
pp. 7-11
Author(s):  
Tariq O. Mohammed ◽  
Naser M. Elkhmri ◽  
Hamza AboBakr
Keyword(s):  
Dynamic Stability ◽  
Incompressible Flow ◽  
Equations Of Motion ◽  
Flight Dynamics ◽  
Unmanned Aircraft ◽  
Aircraft Flight ◽  
Flying Qualities ◽  
Static And Dynamic Stability ◽  
Level 1 ◽  
The Stability

The objective of the present work is to evaluate the static and dynamic stability of the Flying Wing Unmanned Aircraft Vehicle (UAV) model using the Tornado software. The longitudinal and the lateral-directional aerodynamics were studied using the model with incompressible flow, asymmetric, conditions. The stability coefficients were calculated and give proof that the aircraft is statically stable. Using the stability coefficients, the longitudinal and lateral-directional equations of motion were written to evaluate the dynamic stability of the vehicle. Good flying qualities were obtained, rating in Level 1 for the Cooper and Harper scale.

scholarly journals ABOUT THE STABILITY OF NONCONSERVATIVE UNDAMPED ELASTIC SYSTEMS: SOME NEW ELEMENTS

2009 ◽  
Vol 09 (02) ◽  
pp. 357-367 ◽  
Author(s):  
JEAN LERBET ◽  
ELIE ABSI ◽  
ALAIN RIGOLOT
Keyword(s):  
Dynamic Stability ◽  
Dynamic Instability ◽  
Static Stability ◽  
Stability Domain ◽  
Dynamic Approach ◽  
Linear Approach ◽  
Elastic Systems ◽  
The Common ◽  
The Stability ◽  
New Criterion

It is well-known that the domains of static stability and dynamic stability (even for a linear approach) do not match each other when the system is no more conservative and the dynamic approach is usually privileged, meaning that the dynamic stability domain is included in the static one. Following previous works proposing a new criterion of static stability of nonconservative systems and prolonging a paper of Gallina devoted to linear dynamic instability (flutter), we show in this paper some remarkable relations between the two approaches: contrary to the common thought, the new static stability criterion implies partially the dynamic one.

Steering and Stability of Unsymmetric Articulated Railway Vehicles

1979 ◽  
Vol 101 (3) ◽  
pp. 256-262 ◽  
Author(s):  
A. H. Wickens
Keyword(s):  
General Theory ◽  
Dynamic Stability ◽  
Railway Vehicles ◽  
Static And Dynamic Stability ◽  
The Stability

For railway vehicles having coned wheels mounted on solid axles, there is a conflict between the stability of lateral deviations from the motion along the track and ability to steer round curves. A general theory is developed which shows that any articulated, unsymmetric vehicle, which lacks elastic members in the interconnections between wheelsets, can be made stable for running in one direction only. However, an example of a particular configuration of two-axle vehicle shows that the provision of elastic restraint can make it possible to choose vehicle parameters which ensure static and dynamic stability and perfect steering on curves in either direction of motion.

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