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Experimental Research of the Material Filtration Characteristics with Nanofibers Addition

Abstract

Nanofiber properties and the possibilities of their application in industry, including car air intake filtration materials production for vehicle engines are discussed. The attention is paid to the standard filtration materials low efficiency in the range of dust grains below 5 μm. Filtration materials properties with nanofibers addition are presented. Filter paper test conditions and methodology at the station with particle counter were developed. Filtration efficiency characteristics, and accuracy studies as well as filtration materials pressure drop differing in structure were made: standard paper, and materials with nanofibers addition. These are commonly used filter materials for car air intake systems production. Filtration materials with nanofibers addition test results show significantly higher efficiency values, and efficiency for dust grains below 5 μm in comparison with standard filter paper. It was found that there are 16 μm dust grains in the airflow behind the cellulose insert, which may be the reason for the accelerated wear of the engine’s “piston-cylinder” association. Lower dust mass loading km values of filtration materials with nanofibers addition in relation to standard filter papers were observed.

Open access
Experimental Study and Neural Network Modelling of Aerodynamic and Dynamic Characteristics of Flapping Wings Micro Aerial Vehicle

Abstract

The article is close connected with building flying object, that fly like an insect (entomopter). Present work concerns on concept of aerodynamic model using artificial neural networks. Model is used in simulations of flight of entomopter. Aerodynamic model based on experimental data. Necessary data are taken from experiment performed in water tunnel on entomopter model. For this case dynamic test are required. Measurements are ducted during sinusoidal motion of whole model. Modelled object is dipterous. Each wing can perform various spherical motions (wing is rotated around point). The motion of the wing in this case was two-dimensional; it was rotated around two axis. As a model, specially trained neural network is used. For training are used data from measurement. Presented in this article approach is based on artificial neural networks. In this article, innovative concept of model, describing unsteady aerodynamics of entomopter was proposed. It was shown that it could be easily implemented as mathematical model. Unsteady effects related to many state variables can be easily captured. Model can be easily adopted to predict different states of flight by networks training on appropriate data. Test has to reproduce real conditions as close, as it is possible. In reality, it is challenging to design test that will reproduce similar motion.

Open access
The Freight Transport Effectiveness Assessment in the Aspect of the Use of Environmentally Friendly Vehicles

Abstract

The freight transport combines the issue of supply services organization for various types of entities, including large shopping centres, stores of various industries, restaurants, work and leisure places, small-scale outlets, or municipal waste shipments. Due to the location of customers, transport services encounter many difficulties related to infrastructural constraints and increased traffic. This adversely affects the safety and obstructions in traffic and air pollution and thus is a disturbing factor for the lives of inhabitants. There is also a growing problem of the smog in large cities (in Poland, for example, Warsaw or Cracow). Traffic safety, minimization of congestion, and minimization of environmental pollution by transport activities are of particular importance in the development of freight traffic organization plans. In connection with the above, in recent years, the use of Environmentally Friendly Vehicles (EFV) in various spheres of human activity has been dynamically developing, and this concerns the cargo transport. Currently, vehicle manufacturers are providing an increasing number of delivery vehicles and trucks. On the other hand, entrepreneurs planning to implement pro-environmental solutions face a decision problem related to the efficiency of a transport system based on the use of EFV as well as the economic validity of implementing this type of innovation. In connection with the above, in this article, the problem of the impact of transport on the environment and the use of EFV in the freight transport was analysed. The main issues related to the functioning of the transport system and its negative impact on the environment has been presented. Environmental friendly vehicles and their parameters have been characterized. The main decision problems in organizing the transport system, also in the context of the use of EFV, have been identified and analysed. Finally, an example of a model for assessing the efficiency of a transport system with an emphasis on its impact on the environment was presented. The article was concluded with the summary of considerations and the proposal for further work.

Open access
Friction Losses in a Linear Hydraulic Motor as a Result of the Influence of the Control Structure and Oil Viscosity

Abstract

The problem of energy tests of hydraulic systems with hydraulic cylinders, seemingly simple displacement machines, is more complex than that of rotary hydraulic systems. The results of the researches provide an insight into the impact of external loads, required speed, structure of the power supply system, viscosity of hydraulic oil on friction loss, and the efficiency of cylinder drive. The hydraulic cylinder is the strongest structure in the system. Failure of the system is most likely due to failure of the pump supplying the cylinder. The high load of the pump is often caused by the very low energy efficiency of the cylinder, which, despite a relatively low external load, requires high inlet pressure due to large mechanical losses of friction between the piston and the cylinder and between the piston rod and gland. These losses depend on the type of seal used, its shape, the material it is made from, pre-clamp, and the operating parameters of the cylinder. Improperly sealed or assembled seals can cause energy losses of up to 25%. Due to the use of moving seals in the hydraulic cylinder, its energy behaviour is completely different compared to the energy behaviour of a rotary motor, which does not have any seals. The friction force connected with the work of the sealing joints and the mechanical efficiency of the cylinder are determined not only by the external load but also by the method of the applicable supply of the cylinder resulting from the throttling structure, and in particular the pressure level generated in the discharge chamber of the cylinder.

Open access
High Voltage Batteries Diagnostic

Abstract

Hybrid vehicles history begins between XIX and XX century because then has been constructed first hybrid vehicle project. The first men who produced electric propulsion mounted in front hubs connected with generator powered by spark ignition engine was Ferdynand Porsche. Vehicle was called Lohner – Porsche Electromobile. The first en masse produced hybrid vehicle was the first generation Toyota Prius. These model premiere was in 1996, and production started one year later. Vehicle was equipped in 1,5 dcm 58 hp spark ignition engine with added electric propulsion generated 40 mechanical hp. There has been mounting 72 hp spark ignition engine and 44 hp electric generator since 2000. Fuel consumption of these model was 5 liter on 100 km. Beginning XXI century 95% hybrid vehicles were Toyota Prius. The biggest competitor of Toyota Prius was Honda Insight. Lexus and Mercedes started producing hybrid vehicles few years later. The most popular brands selling hybrid vehicles are Toyota and Lexus – Toyota Motor Corporation.

Article describes high voltage battery example diagnostic possibilities in a hybrid or electric vehicle. Constructing vehicle models using two propulsion systems (spark ignition engine and electric generator) cause development and increase control system devices. The measurements has been made by using various diagnostic devices for example: diagnostic scanner mega macs 66, high voltage battery tester. Reading faults code is not enough so it is necessary to use data list what describes this article.

Open access
Impact of the Geometry Accuracy of the Cycloidal Gear Output Shaft with Pins of the Efficiency and Vibrations

Abstract

Cycloidal gear is characterized by [2]:

– Large ratio (up to 171:1) from one stage of reduction, which minimizes the weight and dimensions of the reducer.

– Minimizing the centrifugal forces as the only high-speed element is the input shaft with an eccentric bearing.

– Minimizing internal clearance due to simultaneous meshing of a large number of teeth. In contrast to gears with involute teeth, 10-50% of teeth are found in cycloidal gears with simultaneous meshing. It depends on the size of the gear and the load. The minimum number of teeth engages when running in bulk.

– Low noise and low vibration for large torques and variable speeds.

– High efficiency in a wide range of loads, because rolling elements are used in every place responsible for the transfer of torque.

– Permissible load up to 500% of the rated torque.

All above mention point lead into long-term and trouble-free operation, however the above features require high accuracy. The article described comparison of efficiency, vibration and noise obtained for 3 cycloidal gear modules:

1. Two-disc gear with single rollers for both discs (Chmurawa prototype [1]).

2. Three-disc gearbox with separate rollers for each disc (new idea) with gear components: output shaft with pins, housing with rollers (wheel with internal tooting), and input shaft, made with the manual lathe.

3. The same three-disc gearbox with output shaft with pins made with the CNC. Different levels of accuracy and thus corresponding vibration patterns were obtained.

Open access
Impact of Work of Turbine Adaptive Engines for the Natural Environment

Abstract

The article describes the problem of the operation of turbine jet, adaptive engine work on the natural environment. In particular, the analysis of noise generated by turbine jet engines has been made. It points out possible directions of noise decrease with particular emphasis upon structural changes within the engines, the task of which is to reduce the noise mission. The example of the modernization is based upon the “bypass” type of one-flow turbine jet engine. The essay contains theoretical basis of calculation of the noise emission level and the results, which graphically indicate a relative level of noise of this type of engine depending upon the amount of discharged air and the diameter of the discharge nozzle and the radius, upon the basis of which the noise level is determined. This work also includes a comparison of the relative noise level of this type of engine with regard to one-flow turbine engine equipped with the function of air discharge to the environment and with regard to two-flow turbine jet engine equipped with air stream flow mixing device. The use of low-emission combustion chambers in the “bypass” turbine engine was indicated. This allowed addressing the problem of emissions of toxic exhaust components by this type of aircraft engines. At the same time, the dependence of this emission related to the mass of fuel used on the engine's thrust range was indicated. The article was concluded with a short summary.

Open access
Influence of Geometric Characteristics of the Bomb-Fluger System on its Dynamics

Abstract

The article presents the results of numerical simulations of the bomb-fluger system drop. This system consists of two rigid bodies – a bomb and a fluger, which are connected by a biaxial joint. For the analysis, an author's program was used to simulate the bomb-fluger system drop. Influence of the characteristic points of the system on its stability and dynamics was investigated. Particularly, locations of a bomb mass centre, a fluger mounting point, a fluger aerodynamic focus were tested. The article presents a model of the examined bomb in the wind tunnel, characteristic points of a bomb-fluger system, waveforms of values rate of change angles and the values of angles for different distances, waveforms of values of the angle of nutation and the pitch angle of the fluger relative to the bomb, diagrams of examined points of the location of the centre of the mass and pressure of the fluger, waveforms of values rate of change angles and the values of these angles for different locations of the centre of the mass of the fluger, waveforms of values of the angle of nutation and the pitch angle of the fluger relative to the bomb for different locations.

Open access
The Influence of Granulation and Content of Polyester-Glass Waste on Properties of Composites

Abstract

Glass fibre reinforced composites are used in many branches of industry. Polyester-glass laminates serve as structural material in shipbuilding (e.g. hulls of units, superstructures), in railways, automotive (e.g. elements of car bodies and interior fittings, roofs of wagons, cisterns) or aviation (e.g. aircraft fuselages, fuel tanks, completion beaks and ballasts). Factors affecting the increase of their use include low specific gravity, optimal strength properties, corrosion resistance. This is associated with a large amount of post-production and post-use waste. The recycling problem of these materials remains unresolved. The article presents the technology of processing polyester-glass waste in order to obtain a recycle with a specific granulation. The selected technology for the production of layered composites with reinforcement in the form of recycle is described. For testing, granulation was selected for 1.2 and 3 mm, as well as content: 0%, 10%, 20% and 30%. Using the water-cutting method, samples were prepared according to the standard static tensile test for plastics. The tests were carried out using a universal testing machine as well as an extensometer for samples with granulation of 1.2 mm and 3 mm, as well as the selected recycled percentage. Obtained results of the research indicated that granulation as well as content affects the strength properties of composites. As the granulation increases, at the same content, the material gains less deformation. The increase in the amount of the recycle reduces the strength properties of the material, and also due to the decrease in the deformation value - the material becomes brittle.

Open access
The Influence of Selected Adhesive Properties and the Manner of Surface Preparation upon Impact Strength of Block Adhesive Joints

Abstract

The research described in this article is part of investigating impact strength in block adhesive joints. The authors checked experimentally the effect, on the test results, of the manner of surface preparation and compressive strength and Young’s modulus of an adhesive used to make the connection. The experimental testing was carried out with an impact pendulum tool, designed to examine adhesive joints. During such testing, the energy used to tear off the upper part of the specimen, that is the energy lost by the dropping device, is the measure of the impact strength of an adhesive connection. The elements of the samples were made with an aluminum alloy 2017A. In the investigations, the authors used non-normative samples whose upper element was a cylinder rather than a cuboid, as advised in the norm. The adhesive joints were made using epoxy adhesive Loctite, named EA 3421, or an adhesive composition Epidian 57 with Z1 hardener. The glued elements were prepared by treating the surfaces for bonding by means of the stream-abrasive processing. The abrasive mediums were three types of materials of different gradation. In addition, two series of samples were prepared using roughening by sandpaper. For control samples, the authors made joints, in which the surfaces for bonding became degreased merely by petroleum ether.

The results of the experimental studies indicate that the impact strength of adhesive joints is dependent on the manner of preparation of the bonded elements as well as on the longitudinal modulus of elasticity of the adhesive, which was used to make the connection.

Open access