The car brake system performance has to be reliable at wide range of operating conditions. The friction based braking system reliability strongly depends on cooling capability of disc. According to this, different testing is needed to assure the performance of discs during their design and prototyping phase. The contribution presents the study of cooling capacity of different vented brake disc geometries. Brake disc temperatures during thermal capacity test can exceed 600 C. The temperatures are highly dependent on disc cooling capability. Vented disc have higher cooling capability. There is an open issue which factor has the most significant impact. Is it air flow, air flow distribution, turbulence or …? Brake discs with the same external geometry but different internal geometry were tested on brake dynamometer and subsequently air flow parameters were analysed in cold condition to attempt to explain different maximum temperatures.
Trans Motauto World
Vol. 2 (2017), Issue 4
Table of Contents
TRANSPORT TECHNICS. INVESTIGATION OF ELEMENTS. RELIABILITY
THE APPLICATION OF VIBRATION ANALYSIS FOR DIAGNOSIS OF BEARINGS AND GEARS OF THE REAR AXLE ASSEMBLY OF THE PASSENGER CARSpg(s) 143-146
Predictive maintenance of machines, also known as Condition Based Maintenance, is based on monitoring operating parameters, and comparison with corresponding values of parameters obtained for the new equipment.
All machines with moving parts give rise to sound and vibration and each machine has a specific vibration signature related to the construction and the state of the machine. If the state of the machine changes the vibration signature will also change and a change in the vibration signature can be used to detect incipient defects before they become critical. The condition monitoring technique is based on detecting the presence of a fault, diagnosing the root cause of the fault, assessing its level of severity and making arrangements for its correction. A broad of condition monitoring and fault diagnosis techniques has been carried out for improving the accuracy and ability of condition monitoring and prognosis systems for bearing and gear components.
This paper introduces the method for diagnostic of the rear drive axle for the passenger cars without its demounting. The objective method of diagnosing the rear drive axle is done by vibrometer. Application of diagnostic method greatly would be contributed in quickly localization of the rear drive axle fault where diagnostic process of the servicer will done faster.
TRANSPORT. SAFETY AND ECOLOGY. LOGISTICS AND MANAGEMENT
In the paper is proposed a model for studying of processes in a transport system by fractal methods. In view of the NDS general properties and examined categories: order, chaos and self-organization, the study is based on the synergistic approach to developing systems. On the basis of this has been performed research in the environment Matchcad with different values of system’s parameters.
The paper dwells on the technical and operational parameters affecting the efficiency of the road transport depending upon the performance of the motor transport enterprise. The paper also presents the justifications of criteria indicators to measure performance of road transport, and describes theoretical foundations of the process of studying and assessing the economic efficiency of motor transport systems. The influence of technical and operational parameters on the change in cost fluctuation of transport operation of motor power through a change in the total mileage and indicators that determine the value of variable and fixed costs: carrying capacity, loaded mileage proportion, utilization range, as well as the vehicle utilization, the average road speed and conveying distance. There have been considered three groups of indicators that define the ways and methods for increasing the efficiency of road freight transport in the existing operating conditions of the motor transport company.
PECULIARITIES OF REDUCING THE NUMBER OF CUSTOMS-TRANSPORT FORMALITIES UNDER CORDITIONS OF TIME AND CONVEYING DISTANT CONSTRAINTSpg(s) 152-154
Transport service in modern conditions includes not only cargo transfer itself from suppliers to customers, but also a large number of freight-forwarding, information, customs and transaction operations, cargo handling, insurance and protection services and so on. The introduction of modern logistics management into the customs clearance practice allows for increasing organizational-economic stability of transshipping processes. The paper dwells on the tendencies in the application of customs logistics for the purpose of reducing the number of the customs clearance procedures for vehicles and goods under conditions of time and conveying distant constraints.
Since January this year, all trains of the Dutch Railways use electricity from wind energy. The electricity from this renewable source is increasingly being used in the world. Insight into the future of transportation will provide versions of "Hyperloop" transportation system, a super fast train that can develop a speed of 1.200 kilometers per hour.
At 23rd of January 2017 in Paris started to run the bus without driver also with aim to reduce pollution in the city. In February 2017 the public learnt of a new taxi service in Dubai that will be implemented from June 2017. These are drones on batteries, which are made in China, EHANG 174.
Authorities in Norway have reported that electric or hybrid cars make half of newly registered vehicles in the country during 2017. It is believed that this is a turning point on the way to the Norwegian fleet of electric vehicles and serves as the proof that policy of green transport produces results.
Lot of work is being done to make hydrogen-powered cars a reality. So many automakers are developing hydrogen-powered cars. These hydrogen-powered cars we can expect to see in the near future. Not many people have heard of the technology and from an infrastructure standpoint, purely electric vehicles make more sense. In the new 2017 „Faraday Future“, American manufacturer of electric cars in Las Vegas presented the "new kind of car," electric sedan that will have acceleration of the "Formula 1" and the ability to learn and adapt to the driver. Did "Tesla" won the competition, and it is FF-91, which should be produced in 2018?
STATUS AND PERSPECTIVES OF PORT COMMUNITY SYSTEMS DEVELOPMENT IN THE EUROPEAN UNION: THE CASE OF BULGARIAN BLACK SEA PORTSpg(s) 158-161
The present paper analyses the status and current issues of port information exchange systems in the European Union and the Bulgarian Black Sea ports. Port Community Systems (PCS), being a complement to the Maritime Single Windows (MSW), are based on specific EU legislation thus achieving realization of documentary data exchange in maritime transportation through a single interface with various levels of access. The main objective of this paper is to outline the feasibility, the benefits of PCS development and integration within the European Union as well as the role of the developed MSW system of Bulgarian Black Sea ports for the PCS integration environment. The PCS integration process aims at decreasing of administrative burden, reduction of documentary errors, introduction of standardized electronic data interchange and reduction of service time for port users.
ROLE OF PROJECT PREPARATION IN FORMATION PROFESSIONAL COMPETENCE OF FUTURE SPECIALISTS IN AGROENGENEERINGpg(s) 162-165
New educational standards include significant changes in the structure, content, aims and objectives of education of Agroengineering specialists. According to this the research of the role of project preparation in the professional competence formation of future specialists in agroengeneering was conducted. The results of the investigation the preparatory stages that are based on the systematic approach, which inclines four main components for making an agroengeneer as a specialist be ready for project activity, are represented. Beginning at the first preparatory course the improvement of educational pedagogical technologies should be directed to the target integration of subjects with providing growth of the results at each stage – physics and mathematics, general and special. The role of physical and mathematical education and formation of general professional competence of the future agroengineers, activity and the level of teachers’ influence on the project training of students was investigated.
The dynamic intensity in growth of the number of motor vehicles, and with that the high quantity of exhaust emissions, significantly contributes the air contamination and other serious problems with his quality, especially in urban places. Today, the total number of vehicles globally exceeds 800 million; from witch 300 million are loading freight vehicles. These numbers are disturbing, and the concern is that the constant growth of these vehicles and the consumption of the fossil fuels will continue to raise the negative effects on the environment through the air contamination and to cause serious health problems. In this document is given the analyses for the quality of exhaust emission of diesel engines, identification of the factors which have dominant affect, actual situation about pollution from diesel engines and conclusions about future use of diesel engines vehicles, especially in the countries which are not member of EU.
VEHICLE ENGINES. APPLICATION OF FUELS TYPES. EFFICIENCY
APPLICATION OF 1D SIMULATION TO OPTIMIZE PERFORMANCE AND EMISSIONS OF LARGE GAS ENGINES WITH EXHAUST GAS RECIRCULATIONpg(s) 170-173
Future emission legislation will be increasingly stringent. The current German TA Luft limit for nitric oxide (NOx) emissions from large gas engines is 500 mg/mn3 @ 5% O2 and there is a clear trend toward further reductions. One possible strategy to meet these limits for gas engines is exhaust gas recirculation (EGR). This paper focuses on the application of 1D simulation to a variety of different tasks in gas engine development. First, the basic effects of EGR in gas engines are explained by discussing several 1D simulation results from two 1D simulation models for a large stationary gas engine. A detailed single cylinder engine model is used to study the interaction between the pre-chamber and the main combustion chamber. The boundary conditions are provided by a multicylinder engine model that includes a turbocharger. Based on simulation calculations with both models as well as measurements from a single cylinder research engine, the thermodynamic conditions in the combustion chamber and the gas dynamics are analyzed.
Exergy flow motion insight and analysis of plant requirements for a typical conventional LNG carrier with Rankine regenerative feed water heating steam cycle is given in this paper to clarify and distinguish auxiliary flow streams from the useful ones. Auxiliary flow supports the plant operation, but reduces exergy efficiency by certain amounts. Main boilers exergy flow streams are divided into two major groups: superheated and de-superheated flow stream consumers. A plant run test was carried out by varying main shaft revolutions to collect required thermodynamic data at various plant locations. In the presented marine steam plant is explained exergy flow streams for considering components and flow streams ratios of particular plant components. It is detected and explained the points of excessive auxiliary stream flows consumption and recommendations for possible reduction in saving auxiliary power or steam consumption are given.