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Jet Aircraft Data Acquisition Systems

Abstract

The article presents systems, which record parameters of flight in modern aircraft F-16, which was delivered to Polish Airforce in 2006. With the current level of technical development of the aviation industry, data acquisition systems are an important element of all aircrafts. These systems are responsible for the flight safety, allow reading and storing the most important flight parameters, and combined with digital control and safety systems allow to counteract dangerous situations, which especially can happen often in the case of military aircraft such as the F-16 due to their combat purpose. Systems records basics parameters of plane and engine, as specific fuel consumption or height of flight provides video and audio recording, and aerial combat assistance. These systems record even failures of a braking system during landing. Thanks to modern technology, and devices like those described in this article, F-16 is one of the best fighters in the world. The amount of data provided by analogue and digital sensors is so large that it requires the partitioning of parameters and use of several basic recorders of the entire system is the unit called DAU, or Data Acquisition Unit, which records the most important flight parameters, such as flight time, engine speed, or altitude.

Open access
A Method for Energy Consumption Assessment by Operation of BEV’s in Different Road Conditions

Abstract

For the third time in the history of humankind, it is trying to implement e-mobility. There is a reasonable hope that this attempt will succeed this time. E-mobility is generally regarded as a zero emission. This sentence can only be true in a very small scope, as only in relation to selected parameters and in a very limited its dimension. The situation can change radically. If it will be take into account, the emissions in the production of electricity is necessary for the movement of this type of vehicles Second problem is the energy use amount. We know today that the energy consumption of electric cars, especially in long-term operation is too big. This general knowledge is not confirmed by research results. Both relevant databases and methods of their analysis are missing. This is an unfavourable situation because it is not possible to verify the effects of various changes introduced e.g. in the construction or technology of cars. This publication can be included in those in which it is shown how to change this situation.

The analysis of the results of long-term car use can be used as a verification of various development works, especially in e-mobility, which is only just starting. In the future, it will be need to create the appropriate “big data” databases and a number of tools to analyse the data collected there.

Open access
The Application of Friction Stir Welding (FSW) of Aluminium Alloys in Shipbuilding and Railway Industry

Abstract

The article describes possibilities of application of friction stir welding (FSW) in shipbuilding and railway industry. Actually, in these sectors of industry more and more often modern construction materials are used. The biggest restriction of implementing new materials is technological possibility of joining them. One of construction materials used in the shipbuilding is aluminum, mainly its alloy of 5xxx-aluminium-magnesium series. Its application is justified by good corrosion resistance in seawater and good mechanical attributes. Thanks to susceptibility to plastic treatment, one gains good mechanical attributes with thrice-smaller density than a density of steel, what causes triple reduction of weight of aluminum construction relative to steel one. Alloys of 5xxx series are well weldable. It is generally known that welding is not a good way to joint metals, especially the aluminum. The application of FSW with mixing allows one to change approach to production of aluminum constructions. Using aluminum plates prefabricated with FSW method allows one to reduce time needed for installation of construction and considerably decreases the production costs. The article describes technology and directions of development of friction welding of aluminum alloys of 5xxx series using FSW method. There is also shown analysis of its usefulness in ship and railway industry and comparison of mechanical attributes of weld made with electric arc using MIG (135), TIG (141) method and FSW method.

Open access
The Effect of Adding 2-Ethylhexanol to Jet Fuel on the Performance and Combustion Characteristics of a Miniature Turbojet Engine

Abstract

There are currently many studies undergoing in the field of using alternative fuels for supplying different types of propulsion units. The ASTM standard in the aerospace industry, allows using five different technologies of manufacturing synthetic components apart from standard oil-based fuel for the propulsion of turbine engines (as a blend up to 50% with conventional fuel). One of these is a technology associated with the process of converting alcohols (isobutanol) to jet fuel – Alcohol to Jet (ATJ). In the research performance, emission parameters were measured on laboratory test rig with miniature turbojet engine (MiniJETRig). The test rig has been created in Air Force Institute of Technology for research and development works aimed at alternative fuels for aviation. The miniature engine was fuelled with conventional jet fuel – Jet A-1 and blend of Jet A-1 with 2-ethylhexanol. The results for this blend were compared with the results obtained for neat Jet A-1 fuel in terms of different engine operating modes, according to specified methodology. The conducted tests did not show significant differences in engine operating parameters (thrust, fuel consumption and thrust specific fuel consumption) and the values of CO, CO2 and NOx emission indices between the tested fuels. The engine tests took place in similar ambient conditions. Laboratory tests of selected physicochemical properties were also carried out for both fuel samples.

Open access
Thrust Control Systems of Propulsion and their Verification on Dynamically Positioned Vessels

Abstract

Thrust vector control systems of propulsion systems of dynamic positioning vessels are commonly applied on vessels with DP2 and DP3 class of DP. It was submitted the ways of providing information to dynamic positioning operator DPO about detecting of suspicion of failure in specific thruster and shown the ways of response in such situations. In the case of failure and shut down one of working thrusters, it must be done the possibility assessment of continuation of DP system safe operation. If such situation is not possible, it should be considered the work of DP system on limitations. It was indicated on safety threats during operation of DP systems resulting from system failure or even the design faults. It commonly applies the failure mode and effect analysis (FMEA or FMECA) from the design phase through sea trials until to the verification process during operation. It allows the elimination of majority of faults in the DP systems. It was communicated the basic conditions of safe operation of vessels with DP systems and the examples of conditions which releasing the readiness signal of DP propulsion system elements. Observed development of control and automatics systems will result in increasing the safety of DP systems operation.

Open access
Energy Consumption Estimation of Non-Pneumatic Tire and Pneumatic Tire During Rolling

Abstract

The characteristics of the car tire, and especially its deformation and interaction road, are mainly factors affected the energy consumption of the vehicle and consequently the amount of fuel consumption and emissions to the environment the harmful exhaust gas components. It is estimated that approximately 80-90% of the total energy losses (rolling resistance) are due to internal tire friction, which occurs during its deformation, the remaining 10-20% are ventilation losses, tread face interaction with the road surface and cyclical compression and expansion of air enclosed in the tire. Non-pneumatic tires (NPT) (as a direction of development) are the alternative solutions for conventional tires. Their advantages are as follows maintenance-free and the resistance to typical for pneumatic tires mechanical damages can be a major cause of their widespread use in future (and thus electric) cars. In the available publications, the results of the estimation of the features NPT based on numerical simulations are only presented. There is lack of experimental research results concerning real objects, which determine their driving properties.

Presented work is an attempt to check how the change in wheel structure affects the energy consumption of rolling wheels. Research objects (non-pneumatic tire and pneumatic tire) were selected for the size and destination compatibility. Experimental research were carried out at a universal quasi-static tire testing station, which is located at the Institute of Mechanical Vehicles and Transport at the Department of Mechanical at the Military University of Technology. According to the authors, the obtained results can be an interesting and unique supplement to the problem of assessing the properties of new and future (non-pneumatic tire) construction of vehicle wheels.

Open access
Models of the Reference Departure and Arrival IFR Procedures for the Purpose of Research in RPAS Integration in Controlled Airspace

Abstract

The air operations in controlled airspace performed according to Instrument Flight Rules (IFR) are composed of three main flight phases, i.e. departure, cruise, arrival. Controlled airspace is divided into the terminal area and en-route airspace. The terminal area encloses the departure and arrival phases while the en-route airspace encloses the cruise phase. The IFR procedures are designed for manned aviation to ensure the safety of air operations. Development of the aviation concerns among others the increase in the number of unmanned aviation operations. Currently, on the European level, there is an on-going, long-term program of integration of the unmanned aviation in the uniform (non-segregated) airspace. This work concerns the research in the integration of the Remotely Piloted Aircraft Systems (RPAS) in the IFR procedures of the controlled airports. The objective was to build the reference models of Standard Instrument Departure and Arrival Procedures (SID and STAR). Basing on the procedure design guidelines the models of procedural nominal track, tolerance area, obstacle clearance area, climb or descend gradient, manoeuvres in SID and STAR were done. The guidelines describe the operational minima thus the statistics of existing procedures was done to select the suitable procedure parameters such as a number of navigational points, segments lengths, altitudes, climb or descent gradients. Reference models of SID include straight departure and turning departure procedures. Reference models of STAR include non-precision approach procedures according to used navigational aids, i.e. GNSS, VOR. The reference procedures were numerically implemented which will be used in the further works on RPAS integration problem by simulations of the RPAS ability to execute of the SID and STAR.

Open access
The Influence of the Geometry of the Cutting Edge and Machining Parameters of Duplex Cast Steel After Turning

Abstract

The development and research activity is connected to the production of newer and more functional products. Innovative processes are being developed and applied; services and projects are delivered. Products are work items that should be initially designed, then manufactured and finally sold and utilized. Examples of products may be airplanes, ships, cars, machine tools, gears, crankshafts, drive shaft, tubes as well as gasoline, electricity and gas, etc. The product has to meet the expectations of the future use. It is characterized by a set of functional features. In the case of machines and their capabilities and performance, for example, durability, reliability, resulting from the characteristics represented by the structural units forming the structure. The formation of the desired features of the surface layer in the technological process is an important problem due to the ability of the elements of kinematic pairs to fulfil the function as long as possible foreseen for them. The article presents results of experimental studies of turning cast steel grade GX2CrNiMoCuN25-6-3-3. The aim of the research was to determine the geometry of the cutting edge and the technological parameters of cutting that are conducive to obtaining the roughness in the field of very accurate machining. It can achieve the appropriate technological quality of the workpiece surface. After these experimental studies was determined that there is a reduction roughness using suitable inserts. Turning was made for the duplex cast steel. The technological parameters of machining process were used: feed rate f = 0.1-0.2 mm/rev, depth of cut ap = 0.5 mm, cutting speed vc = 50-100 m/min. Turning was made using universal lathe CDS 500x1000 equipped with CCMT carbide tipped inserts.

Open access
The Effect of Using the Kline-Fogleman Modification Upon the Coefficient Characteristics of Aerodynamic Forces in the Airfoil

Abstract

The wing is the main aircraft construction element, whose main task is to produce the lift, balancing the aircraft weight as well as ensuring the execution of all flight states for which the aircraft was designed. The selection of appropriate airfoils or the development of new ones is one of the most important constructions goals. As a rule, constructors aim at ensuring a sufficiently large lift with little aerodynamic drag in order to increase the scope of utility angles of attack and such shaping of these characteristics so that the aircraft performance, close to the critical angles of attack, guarantees an adequate level of safety. One of the methods of improving the aerodynamic properties of airfoils is the Kline-Fogleman modification. It involves an application of a step into the airfoil contour at a place. It enforces the creation of a swirling air stream, preventing the separation and maintaining airflow over the profile and thus the reduction of drags, as well as delaying separation. The use of this type of a solution is justified when designing unmanned aerial vehicles, of small sizes, which move with slow speeds and sometimes-large angles of attack, including those close to critical angels of attack. The Kline-Fogleman modification decreases the likelihood of aircraft stalling.

The aim of this work is to present an analysis of airflow over NACA0012 airfoil with Kline-Fogleman modification. The calculations were made by solving the problem of numerical fluid mechanics. For calculations, the Comsol Maribor programme was used. The investigation focused on several different airfoil modifications (KFm-1, KFm-2, KFm-3). This enabled a selection of a solution, providing the most desirable aerodynamic characteristics.

Open access
The Errors of the Numerical Calculations of Dynamic Characteristics of Cantilever Beam Mounted on the Plate

Abstract

The safety, comfort of the crews, stability, economics of the equipment when ship operating is the leading requirement in the field of designing and manufacturing marine structure and machinery. As a result, all parts of the ships must be tested and inspected to meet the basic safety requirements of the shipping association. The design, manufacture, testing in the maritime field in general and shipbuilding sector in particular are expensive, time consuming: such as aerodynamic experiments of the engine, collision test, ship manoeuvring, vibration test and balance of deck beams, hull beams, hatch covers, shafts...thus experimental works are sometimes impossible. Along with the development of computer science, many numerical models and software programs have been developed to solve these difficult problems. There are many numerical modelling methods, starting with the finite difference method, the boundary element method, the finite element method, the no mesh method, the weight residue or the energy method. The Work will be limited to the analysis of the most popular numerical modelling method - finite element method using Patran and Nastran software. In the first step of our research, T-beam was analysed as a part of ship hull structure (thin-walled structure). The article goes into the analysis of the accuracy of selected numerical models for the natural vibration frequency of the T-beams mounted on the plate. After modelling, calculating the natural frequency of the T-beam using the Patran - Nastran software, the results were compared with the theoretical values. From that, we evaluate the dispersion and error of different numerical models and select the optimal numerical model. Optimal model will be used for modelling full ship hull with superstructure.

Open access