Wyniki wyszukiwania - BazTech

1

Calibration of micro-simulation model in assessment of passenger car exhaust emission during acceleration

Nowak Mateusz

Combustion Engines

|

2022

|

R. 61, nr 2

54--59

EN

In terms of simulation research, it is important to simulate real conditions as precisely as possible. This type of approach makes it possible to minimize the error in the obtained results. The dynamics of acceleration is one of the most important factors having a direct impact on fuel consumption and exhaust emissions from vehicles. The work was carried out with the use of PTV Vissim microscopic vehicle motion simulation software. The considerations were carried out on theoretical acceleration profiles with different dynamics values and the actual character of acceleration, recorded during road tests. The simulations were carried out for a car powered by spark-ignition and compression-ignition engines. The research showed that the calibration of the acceleration character of the vehicle in simulation tests may result in significant differences in obtained results of exhaust emissions.

2

About diagnosing of impact of railway vehicles on the track

Cherniak G., Domin R., Nozhenko O., Mostovych A.

Prace Naukowe Politechniki Warszawskiej. Transport

|

2016

|

z. 112

59--69

EN

The report presents the results of the research aimed at justification of expediency of creating a system of experimental evaluation of indicators of impact of the rolling stock on the rails. The proposed system is based on the measurements of the vertical and horizontal accelerations of the rails under a movement of the rolling stock on the raił track section. This system for monitoring rail accelerations that are emerging from the impact of the rolling stock in the track structure is expected to be used to identify vehicles with high impact on the rails due to their design and technical condition of the running gears, including the defects of the wheels. Some results of the pilot testing of the proposed system for the monitoring of the accelerations, which were registered by passing the train consisting of five units, are presented. And the computational algorithm of the specialized pre-processing of the multidimensional signal that is recorded by this system is described. The offered algorithm in automatic mode allows dividing the signal on the separate segments that are associated with the particular wheelsof a running train for subsequent analysis of each segment. This algorithm does not reąuire input data about the train speed on the track section that is eąuipped with the monitoring system, about the number of wheelsets of the running train, and about the distances between them. These data are calculated as a result of the algorithm execution, sińce they are absent under the operating conditions of the proposed system.

3

Wyznaczanie lokalnego pochylenia niwelety drogi z wykorzystaniem akcelerometru zabudowanego w urządzeniu mobilnym

Honkisz M., Brzozowski K.

TTS Technika Transportu Szynowego

|

2015

|

R. 22, nr 12

636--640, CD

PL

W artykule przeanalizowano wyniki rejestracji przyspieszenia pojazdu związanego z lokalnym pochyleniem niwelety drogi pozyskane z wykorzystaniem prostego systemu pomiarowego. Jednostkę centralną systemu stanowi urządzenie mobilne z zabudowanym akcelerometrem trzyosiowym. W ramach badań zrealizowano szereg jazd testowych po wybranym odcinku drogi publicznej, a następie do dalszej analizy wybrano dwa przejazdy z porównywalnymi przebiegami prędkości. W odniesieniu do zarejestrowanych przyspieszeń przedstawiono ocenę jakościową i ilościową. Wyznaczone na podstawie przyspieszenia pochylenie niwelety porównano z pochyleniem rzeczywistym.

EN

In the paper, results concerning recorded acceleration of a vehicle due to local uphill gradient were analyzed. The data was obtained by means of using a simple measurement system. The main unit of the system is a mobile device with a three axis accelerometer, which is builtin. In the framework of the research, several test drives were done on a public road. Then two drives with similar velocity profiles were chosen to further analysis. The evaluation of recorded acceleration was performed from qualitative and quantitative point of view. Road uphill gradient, calculated on the base of acceleration, was compared to real data.

4

Investigation of dynamic properties of vehicle in various friction condition simulated with use of skidcar system

Žuraulis V., Kemzūraitė K., Więckowski D.

Archiwum Motoryzacji

|

2014

|

Vol. 63, nr 1

89--99, 195--205

EN

In this paper, the friction characteristics of a vehicle equipped with skidcar system are analyzed. Skidcar system with attached additional wheels helps to regulate the adhesion with the road surface. Easy slipping vehicle is a useful device for driving skills improvement, carrying out various vehicle dynamics and control research activities. Important reason of skidcar systems is an ability to set low friction values in dry and good contact road conditions. Regulation of friction characteristics extends the limits of the system operation. In this case, the identification of friction characteristics is important. Vertical load of wheels and critical horizontal forces are measured in each operating mode by changing skidcar system height. Furthermore, IS04138 driving manoeuvre is performed to measure the vehicle accelerations, oscillations and slip parameters for friction evaluation in dynamic state. The performed analysis could be useful for drivers training and for further vehicle stability and control researches upon using skidcar system.