Wheel–Rail Impact Loads, Noise and Vibration: A Review of Excitation Mechanisms, Prediction Methods and Mitigation Measures

Author(s):  
Jens C. O. Nielsen ◽  
Astrid Pieringer ◽  
David J. Thompson ◽  
Peter T. Torstensson
2019 ◽  
Vol 255 ◽  
pp. 02015
Author(s):  
Siang Chuan Yeo ◽  
Meng Hee Lim ◽  
Hoe Cheng Eng

This paper is about predicting the noise and vibrations for railways project in Malaysia by using Finite Element Analysis method. In recent years, Malaysia is massively developing railways industry. This has created a great awareness in the public, regarding noise and vibration from railways trains during operations are generated from the rolling interaction of the wheels with the rails. Additional noise may be generated from brake squeals during braking at the stations and curved segments of the rail alignments. Over the years, it is relatively easy to measure the acoustic sound power of a train and to calculate noise levels. However, it would be advantageous to be able to reliably and efficiently predict the noise and vibration impact resulting from proposed railways projects. Comprehensive noise and vibration shall be predicted to determine noise and vibration levels along the entire track alignment to ensure that noise and vibration levels shall comply with Malaysia Department of Environment (DOE) approved limits. The result of analyses can be used to identify and to design noise and vibration mitigation measures for the entire railway project. Several methods have evolved to predict noise and vibration from various operational sources, but their suitability for prediction of noise and vibration from railways trains is not well known and has not yet been thoroughly tested. This study document finite element analysis undertaken for the noise and vibration aspects of the viaduct design of the railways track. Data and inputs for finite element model and analysis are including the aspect of “Geometry, atmospheric, ground effect, analysis type and boundary conditions”, as mentioned by Makarewicz (1998) and Lamancusa (2009). A comparison of finite element model and analysis will be conducted by adding the additional aspects of “Material properties and applied loads”, which to be determined as better accuracy of predicting noise and vibration from railways train.


CICTP 2020 ◽  
2020 ◽  
Author(s):  
Jiyuan Tan ◽  
Qianqian Qiu ◽  
Shuofeng Wang ◽  
Na Xie ◽  
Yuelong Su ◽  
...  
Keyword(s):  

2014 ◽  
pp. 70-91 ◽  
Author(s):  
I. Bashmakov ◽  
A. Myshak

This paper investigates costs and benefits associated with low-carbon economic development pathways realization to the mid XXI century. 30 scenarios covering practically all “visions of the future” were developed by several research groups based on scenario assumptions agreed upon in advance. It is shown that with a very high probability Russian energy-related GHG emissions will reach the peak before 2050, which will be at least 11% below the 1990 emission level. The height of the peak depends on portfolio of GHG emissions mitigation measures. Efforts to keep 2050 GHG emissions 25-30% below the 1990 level bring no GDP losses. GDP impact of deep GHG emission reduction - by 50% of the 1990 level - varies from plus 4% to minus 9%. Finally, very deep GHG emission reduction - by 80% - may bring GDP losses of over 10%.


Author(s):  
A. Z. A. Mazlan ◽  
M. H. A. Satar ◽  
M. H. Hamdan ◽  
M. S. Md. Isa ◽  
S. Man ◽  
...  

The automotive heating and ventilating air condition (HVAC) system, when vibrating, can generate various types of noises such as humming, hissing, clicking and air-rushes. These noises can be characterised to determine their root causes. In this study, the humming-type noise is taken into consideration whereby the noise and vibration characteristics are measured from various HVAC components such as power steering pump, compressor and air conditional pipe. Four types of measurement sensors were used in this study - tachometer for rpm tracking; accelerometer for the vibration microphone for the noise; and sound camera for the visualization measurement. Two types of operating conditions were taken into consideration - they were “idle” (850 rpm) and “running” (850-1400 rpm) conditions. A constant blower speed was applied for both conditions. The result shows that the humming noises can be determined at the frequency range of 300-350 Hz and 150-250 Hz for both idle and running conditions, respectively. The vibration of the power steering pump shows the worst acceleration of 1.8 m/s2 at the frequency range of 150-250 Hz, compared to the compressor and air conditional pipe. This result was validated with the 3D colour order and sound camera analyses, in which the humming noise colour mapping shows dominance in this frequency range.  


CIM Journal ◽  
2015 ◽  
Vol 6 (2) ◽  
pp. 111-117
Author(s):  
Marcel Laflamme ◽  
Pierre Marcotte ◽  
Jérôme Boutin ◽  
Sylvain Ouellette ◽  
Gilles LeBlanc

Author(s):  
S. K. Tomar ◽  
A. Kaur ◽  
H. K. Dangi ◽  
T. Ghawana ◽  
K. Sarma

One of the major challenge from unplanned growth in the cities is the fire incidents posing a serious threat to life and property. Delhi, the capital city of India, has seen unplanned growth of colonies resulting in a serious concern for the relevant agencies. This paper investigates the relation between potential causes of fire incidents during 2013-2016 in South-West Delhi Division of Delhi Fire Services as part of risk analysis using the data about fire stations & their jurisdictions, incidents of fire, water reservoirs available, landuse and population data along with the divisional & sub-divisional boundaries of South-West Delhi division under Delhi Fire Service. Statistical and Geospatial tools have been used together to perform the risk analysis. The analysis reveals that difference in actual occupancy and defined landuse as a part of unplanned growth of settlements is found to be the main reason behind the major fire incidents. The suggested mitigation measures focus on legal, policy, physical & technological aspects and highlight the need to bring the systemic changes with changing scenario of demographics and infrastructure to accommodate more aspects of ground reality.


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