AN IMPROVED ARMORED VEHICLE KRAZ “FIONA” NOISE SILENCER

2019 ◽  
pp. 21-26
Author(s):  
Volodymyr Fedorov ◽  
Vasyl’ Yanovsky ◽  
Dmytro Kovalshuk
Keyword(s):  
Noise Reduction ◽  
Speed Of Sound ◽  
Acoustic Waves ◽  
Noise Level ◽  
Combustion Engine ◽  
Environmental Aspect ◽  
Exhaust Gases ◽  
Ecological Requirements ◽  
On The Road ◽  
Armored Vehicle

Ecological requirements for cars grow from year to year, both in the world as a whole, and in Ukraine in particular. This is especially true of noise pollution. Additionally, noise reduction becomes relevant, taking into account the conduct of military operations during the last 5 years on the territory of Ukraine. The war has caused a special need for military vehicles for which masking properties are vital. Noise is a serious disincentive factor. Therefore, its reduction for a military vehicle, apart from the environmental aspect, is of a purely military nature, that is, it is extremely important. The car has many sources of noise there are many ways to deal with them. One of the most powerful source of noise is the sleeping bag. This kind of noise is reduced by means of silencers of noise. The vast majority of silencer data in the basis of its design has a reactive (or resonant) muffler. To calculate the jet silencer you must know the speed of sound in the sleeping bags. In order to increase the acoustic efficiency of reactive and resonant mufflers of exhaust gases noise of the ICE of cars, an experimental method was proposed for determining the speed of sound in the sleighs. Implementation of the method is carried out by measuring the attenuation of acoustic waves. The noise level of the bedrooms is measured without silencer and silencer. Based on the data obtained, the noise reduction performance of the residual is established. From the well-known formula, based on the calculation of the efficiency of the silencing of a jet muffler, a formula is obtained for calculating the speed of sound in the sleeping quays. In this formula, all parameters are known: the level of silencer efficiency, the noise level of the sleeping, the ratio of areas of cross sections of the muffler and the inlet pipe and the length of the muffler. The sound speed thus established can continue to be used not only for engines of the type for which measurements and calculations were made, but also with a certain approximation for some other types of engines. This method provides high accuracy for determining the required parameter. In the given work on the example of the armored car KrAZ “Fiona” the calculation of efficiency increase of the reactive silencer is made due to the above-mentioned method. Also, the projected decrease in the external noise level of the KrAZ Armored Vehicle “Fiona” is considered by determining the speed of sound in the recesses on the trunk cycle on the road with acceleration up to speed of 50 km/h (75 km/h) and the movement with this speed, as well as when driving at a speed of 45 km/h. Keywords: transport, armored car, internal combustion engine, exhaust, exhaust gases, noise, source, acoustic efficiency, acoustic efficiency, speed of sound, jet muffler.

Investigating Acoustic Excitation and Reburn Interaction on NOx Concentration in Bio-Fuel Engines Exhaust

2020 ◽  
Author(s):  
Nellimala Abdul Shukoor ◽  
Mohamed I. Hassan Ali ◽  
Rijo Jacob Thomas
Keyword(s):  
Acoustic Wave ◽  
Acoustic Waves ◽  
Alternative Fuels ◽  
Internal Combustion Engines ◽  
Combustion Engine ◽  
Nox Reduction ◽  
Internal Combustion ◽  
Vertical Tube ◽  
Acoustic Excitation ◽  
Exhaust Gases

Abstract Although gasoline and diesel fuels are likely to continue fuelling the internal combustion engines for the near future, there is an increasing concern over the emission of greenhouse gases and other environmental pollutants. Alternative fuels such as biofuels are promising as they are renewable, sustainable, and reduce engine emissions. However, nitric oxides (NO) and nitrogen dioxides (NO2) are typically released in greater proportion, generally known as NOx. Applying acoustic excitation on a biofuel operated engine exhaust gases is investigated with and without reburn. Four biofuels, namely Jatropha, Karanja, Palm and neem oils, are burned in a single-cylinder Internal Combustion Engine (ICE). The exhaust gases is carried out through a vertical tube where a trace of liquid petroleum gas (LPG) is injected before it passes an acoustic cross tube. Variable frequency acoustic waves were passed through the setup using a speaker and amplifier. NOx is sampled from the top of the vertical tube. Acoustic wave frequency, LPG reburn, and combination of both acoustic waves and reburn influence on NOx mitigation are investigated. The integration of acoustic wave excitation and reburn showed the most significant reduction in the NOx. The second-largest NOx reduction was achieved with the sole use of reburn technology. Integrating the acoustic excitation with reburning was found to produce about 80% NOx reduction at a range of 100–150 Hz for all tested biodiesel fuels. Out of the fuels under consideration, Neem Oil generated the lowest amount of NOx and showed 87% reduction in NOx.

TO THE QUESTION OF THE IMPACT OF CLIMATE CHANGE ON THE ECOLOGICAL STATE OF ARTIFICIAL PLANTATIONS OF PITSUNDSKAYA PINE IN THE SEASIDE AREA OF GELENDZHIK

2017 ◽  
Author(s):  
Elizaveta Derevenets ◽  
Elizaveta Derevenets
Keyword(s):  
Negative Impact ◽  
Standard Technique ◽  
Negative Influence ◽  
Exhaust Gases ◽  
The Road ◽  
Industrial Enterprises ◽  
Federal Highway ◽  
On The Road ◽  
The Impact ◽  
The City

Gelendzhik is the resort town, there aren't a lot of industrial enterprises here. The main pollutant is transport. The work purpose is the assessment of a condition of the artificial landings of a pine located along the Federal highway "Don" and landings, which is nearly the sea coast. Researches were conducted to a standard technique of the General vital state (A. S. Bogolyubov). The assessment of a condition of pines was carried out during 6 years: from 2010 to 2015. For carrying out research we used 6 experimental grounds on the Markotkhsky spine and 2 control grounds within the town. We investigated 24 trees on each platform, middle age of the trees were 30 - 40 years. Results. 1. The condition of trees in the pine forests located in immediate proximity with the Federal highway "Don" (No. 1, 2, 3) is unsatisfactory. As even weak influences of the majority of atmospheric gaseous pollutants (sulphurous gas, nitrogen oxides, etc.) give effect of a necrosis and hloroz of pine needles, the condition of pines is connected with technogenic pollution. So near the Federal highway "Don" the air environment is strongly polluted by exhaust gases. Information of 2012 confirm that negative influence of the route on Markotkh's vegetation decreases at reduction of load of the route. 2. On the sites located above on a slope (No. 4,5,6) thanks to remoteness and the wind mode intensity of influence of pollutants is lower and a condition of pines the quite satisfactory. 3. Trees on the sites located near the sea (No. 7,8) are in a good shape. Small deterioration of a state is noted in very droughty years. Conclusion. Results of six years' research show that the condition of the plantings which are in close proximity with the road worsens. It is explained by increase in intensity of the movement on the road, especially during a resort season. Gelendzhik is the city with a good ecological shape, but the damage to environment is already caused. If not to take measures, we can lose a unique part of the nature in the future, recreate it will be impossible. Measures of reduction of negative impact of exhaust gases were offered. Results of researches are transferred to ecological department of the City administration of Gelendzhik.

TO THE QUESTION OF THE IMPACT OF CLIMATE CHANGE ON THE ECOLOGICAL STATE OF ARTIFICIAL PLANTATIONS OF PITSUNDSKAYA PINE IN THE SEASIDE AREA OF GELENDZHIK

2017 ◽  
Author(s):  
Elizaveta Derevenets ◽  
Elizaveta Derevenets
Keyword(s):  
Negative Impact ◽  
Standard Technique ◽  
Negative Influence ◽  
Exhaust Gases ◽  
The Road ◽  
Industrial Enterprises ◽  
Federal Highway ◽  
On The Road ◽  
The Impact ◽  
The City

Gelendzhik is the resort town, there aren't a lot of industrial enterprises here. The main pollutant is transport. The work purpose is the assessment of a condition of the artificial landings of a pine located along the Federal highway "Don" and landings, which is nearly the sea coast. Researches were conducted to a standard technique of the General vital state (A. S. Bogolyubov). The assessment of a condition of pines was carried out during 6 years: from 2010 to 2015. For carrying out research we used 6 experimental grounds on the Markotkhsky spine and 2 control grounds within the town. We investigated 24 trees on each platform, middle age of the trees were 30 - 40 years. Results. 1. The condition of trees in the pine forests located in immediate proximity with the Federal highway "Don" (No. 1, 2, 3) is unsatisfactory. As even weak influences of the majority of atmospheric gaseous pollutants (sulphurous gas, nitrogen oxides, etc.) give effect of a necrosis and hloroz of pine needles, the condition of pines is connected with technogenic pollution. So near the Federal highway "Don" the air environment is strongly polluted by exhaust gases. Information of 2012 confirm that negative influence of the route on Markotkh's vegetation decreases at reduction of load of the route. 2. On the sites located above on a slope (No. 4,5,6) thanks to remoteness and the wind mode intensity of influence of pollutants is lower and a condition of pines the quite satisfactory. 3. Trees on the sites located near the sea (No. 7,8) are in a good shape. Small deterioration of a state is noted in very droughty years. Conclusion. Results of six years' research show that the condition of the plantings which are in close proximity with the road worsens. It is explained by increase in intensity of the movement on the road, especially during a resort season. Gelendzhik is the city with a good ecological shape, but the damage to environment is already caused. If not to take measures, we can lose a unique part of the nature in the future, recreate it will be impossible. Measures of reduction of negative impact of exhaust gases were offered. Results of researches are transferred to ecological department of the City administration of Gelendzhik.

Comparison of Noise Reduction Performance Evaluation Methods for Low-Noise Pavement in Korea- Part

2021 ◽  
Vol 263 (4) ◽  
pp. 2930-2939
Author(s):  
Byungchae Kim ◽  
Hyunjin Kim ◽  
Wonuk Kang
Keyword(s):  
Noise Reduction ◽  
Noise Level ◽  
Measurement Method ◽  
Road Traffic ◽  
Low Noise ◽  
Management Standards ◽  
Close Proximity ◽  
Porous Pavement ◽  
Reduction Effect ◽  
Measurement Location

In Korea, road noise is assessed as a measurement method of exterior noise emitted by road vehicle for management standards by the National Institute of Environmental Sciences. In this method, the noise felt at the actual pickup point is measured as LAeq (the roadside equivalent noise level). Recently, to clarify the standard for measuring noise on low-noise pavements, the CPX (ISO11819-2; Close-proximity method) was first introduced in the Porous Pavement Guidelines of the Ministry of Land, Infrastructure and Transport. According to ISO, the CPX adopts the side microphone as a mandatory measurement location, and the rear optional. The side location has been a mandatory due to its high correlation with SPB (ISO 11819-1, Statistical Pass-by method). However, according to our previous study on the correlation evaluation between L and CPX rear microphone noise level, both noise reduction effect was about 9-12 dB(A) showed a high correlation in Korea where heavy road traffic is common. The following study aims to show the consistent correlation between the L and CPX rear noise level. Furthermore, it is intended to be helpful in selecting the location of the CPX microphone that can most effectively represent the actual noise on the low-noise pavement in Korea.

REDUCTION OF EXTERNAL NOISE VEHICLE of SPAI “BOHDANA” ON THE BASIS OF THE KrAZ-63221 IMPROVED TWO-CHAMBER REACTIVE NOISE SILENCER

2021 ◽  
pp. 29-35
Author(s):  
Volodymyr Fedorov ◽  
Halyna Filipova ◽  
Vasyl Yanovsky
Keyword(s):  
Negative Impact ◽  
Combustion Engine ◽  
External Noise ◽  
Independent State ◽  
Exhaust Gases ◽  
Military Equipment ◽  
Military Vehicles ◽  
Internal Partition ◽  
Two Parameters

High-quality military equipment is a vital necessity for the independent state of Ukraine, especially in the conditions of aggravation of the situation at the front. One of the parameters that determines the quality of military vehicles is the level of external noise. The external noise of this type of car, in addition to the negative impact on human health (including the crew), is also an unmasking factor. In order to reduce the level of external noise of SPAI “Bogdan” on the basis of the chassis KrAZ-63221, the use of an advanced two-chamber jet muffler of the exhaust gases of the internal combustion engine is proposed. The known two-chamber jet muffler of exhaust gases has a fixed internal partition. Its acoustic efficiency is described by a known formula. It is proposed to make the inner partition of the muffler movable. This need arises from the fact of constant changes in the speed of the engine crankshaft during the movement of the car. The change in the position of the inner partition is consistent with the change in the speed of the crankshaft, because these two processes are synchronized. The mathematical package IDL was used to analyze the known formula for the efficiency of a two-chamber jet exhaust muffler of an engine with a movable inner partition. Given the need to show the dependence of the efficiency of the muffler simultaneously on two parameters – the speed of the crankshaft and the position of the movable inner partition of the muffler – the method of color coding was chosen. The design of a two-chamber jet noise muffler developed for ACS “Bogdan” is given. As a result of introduction of the developed muffler noise reduction of level of external noise of the SPAI “Bogdan” on the basis of the chassis KrAZ-63221 car on 2–3,5 dBA in the range of speeds of movement of 45–85 km/h is forecasted.

scholarly journals Experimental Study of Pipes Shape Effect on Noise Reduction

2017 ◽  
Vol 5 (1) ◽  
pp. 71-86
Author(s):  
Muna S. Kassim ◽  
Ammar Fadhil Hussein Al-Maliki
Keyword(s):  
Experimental Study ◽  
High Pressure ◽  
Noise Reduction ◽  
Power Plants ◽  
Combustion Engine ◽  
Exhaust System ◽  
Noise Pollution ◽  
Shape Effect ◽  
Pipe Length ◽  
Exhaust Noise

Internal combustion engine is a major source of noise pollution. These engines are used for various purposes such as, in power plants, automobiles, locomotives, and in various manufacturing machineries. The noise is caused by two reasons; the first reason is the pulses which created when the burst of high pressure gas suddenly enters the exhaust system, while the second reason is the friction of various parts of the engine where the exhaust noise is the most dominant. The limitation of the noise caused by the exhaust system is accomplished by the use of silencers and mufflers. The aim of this study is the reduction of the noise by changing its inlet and outlet pipe length and shape. Also the losses in noise for different length and shapes have been investigated experimentally. The results show that the corrugated pipe is preferable for noise reduction.

scholarly journals The influence of exhaust system leak on the operating parameters of a turbocharged spark ignition engine

2018 ◽  
Vol 19 (6) ◽  
pp. 468-472
Author(s):  
Krystian Hennek ◽  
Mariusz Graba
Keyword(s):  
Oxygen Sensor ◽  
Combustion Engine ◽  
Exhaust System ◽  
Spark Ignition Engine ◽  
Si Engine ◽  
The Road ◽  
Torque Measurements ◽  
Si Engines ◽  
Common Technique ◽  
On The Road

Turbocharging of an internal combustion engine is the most common technique to improve an engines’ performance. In present it is not hard to meet vehicles on the road with turbocharged SI engines, which have a high mileage, and because of this fact there is a high risk of exhaust systems leak. This might have its influence not only on the emissions, but also on the vehicles performance. Thereby this dissertation shows the comparative analysis of the influence of exhaust system leak in the catalyzer input on the exhaust gasses composition in the catalyzer output and the operation parameters of an turbocharged SI engine. During the research some parameters were recorded and compared, e. g.: the engines power and torque, the injec-tors opening time, the oxygen sensors voltage signals in the input and in the output of the catalyzer, the concentration of harmful gasses in the exhaust tailpipe. The research was conducted with the use of a single roller MAHA MSR 500 chassis dynamometer. A series of torque measurements was performed. Under these measurements a simulation of the exhaust system leakage of a turbocharged SI passenger car engine was made. As a result three variations of the wideband oxygen sensor acting were reached. The wideband sensor is mounted between the turbocharger unit and the input of the catalyzer. In the test the influence of the leakage on the injector’s opening time and the composition of harmful exhaust substances were pointed.

scholarly journals The End of the M.E.?

2005 ◽  
Vol 127 (05) ◽  
pp. 26-29 ◽  
Author(s):  
Peter Huber ◽  
Mark P. Mills
Keyword(s):  
Fuel Cell ◽  
Mechanical Engineering ◽  
Combustion Engine ◽  
Electrical Power ◽  
Single Step ◽  
Second Century ◽  
Basic Operation ◽  
The Road ◽  
Energy Economy ◽  
On The Road

This article highlights that mechanical engineers control most of the rest of our energy economy. The engineering focus will shift inexorably toward finding the most efficient means of generating electricity on-board. Trains and monster trucks both use big diesel generators. Hybrid cars on the road today burn gasoline, but it is the fuel cell that attracts the most attention from visionaries and critics of the internal combustion engine. Remarkably elegant in its basic operation, the fuel cell transforms fuel into electricity in a single step, completely bypassing the furnace, turbine, and generator. In this scenario, mechanical engineering ultimately surrenders its last major under-the-hood citadel to chemical engineers. One might say that the age of mechanical engineering was launched by James Watt's steam engine in 1763, and propelled through its second century by Nikolaus Otto’s 1876 invention of the spark-ignited petroleum engine. We are now at the dawn of the age of electrical engineering, not because we recently learned how to generate light-speed electrical power, but because we have now finally learned how to control it.

An Analysis of Energy Flow in Diesel Engine on AVL-Boost

2021 ◽  
Vol 31.2 (149) ◽  
pp. 40-46
Keyword(s):  
Diesel Engine ◽  
Working Conditions ◽  
Energy Flow ◽  
Combustion Engine ◽  
Cooling Water ◽  
Exhaust Gases ◽  
Operating Modes ◽  
Useful Power ◽  
System Energy ◽  
Coolant System

Energy achieved by burning fuel in an internal combustion engine (ICE) is divided into several main parts such as useful power, heat transfer for coolant system, energy of exhaust gases and mechanical losses. A detailed analysis of the quantity and distribution of these components will be an essential basis in the study of ICE improvement. In this paper, the authors present the calculation of energy distribution on D243 diesel engine through simulation on AVL-Boost. The results showed that the average thermal efficiency of the ICE during all operating modes was 25.8%. The total energy transfer for the coolant system and the heat of exhaust gases is 63.54% and reaches maximum 103.7 kW in rated mode. The acquired results can be used as a research basis to improve the economics and technical aspects of ICE such as optimization of working conditions of coolant and lubricating systems. As well as calculate the equipment of turbocharger or systems that utilize energy of exhaust gases and cooling water.

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