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Abstract

The paper presents a numerical model of car exhaust pollutant dispersion. The model can be used for estimation of the impact of pollutant emissions from road vehicles on the environment. The finite volume method has been used for model formulation. Equations obtained after discretisation are solved by using different methods like Runge-Kutta, Crank-Nicholson or decomposition methods. On the basis of the numerical simulation, conclusions are formulated about the numerical effectiveness of the integration methods used. In the paper, a problem of nitrogen oxides dispersion is formulated and solved, whereby chemical reactions are included in considerations. The model presented in the paper has been used for numerical calculations of car exhaust pollutant concentrations in a real car park. The last part of the paper presents some numerical results of calculations, which include emissions after cold start of engines.
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Authors and Affiliations

Krzysztof Brzozowski
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Abstract

This article reports the effects of CuO/water based coolant on specific fuel consumption and exhaust emissions of four stroke single cylinder diesel engine. The CuO nanoparticles of 27 nm were used to prepare the nanofluid-based engine coolant. Three different volume concentrations (i.e 0.05%, 0.1%, and 0.2%) of CuO/water nanofluids were prepared by using two-step method. The purpose of this study is to investigate the exhaust emissions (NOx), exhaust gas temperature and specific fuel consumption under different load conditions with CuO/water nanofluid. After a series of experiments, it was observed that the CuO/water nanofluids, even at low volume concentrations, have a significant influence on exhaust emissions. The experimental results revealed that, at full load condition, the specific fuel consumption was reduced by 8.6%, 15.1% and 21.1% for the addition of 0.05%, 0.1% and 0.2% CuO nanoparticles with water, respectively. Also, the emission tests were concluded that 881 ppm, 853 ppm and 833 ppm of NOx emissions were observed at high load with 0.05%, 0.1% and 0.2% volume concentrations of CuO/water nanofluids, respectively.

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Bibliography

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[2] M.A. Akhavan-Behabadi, F. Hekmatipour, S.M. Mirhabibi, and B. Sajadi. Experimental investigation of thermal–rheological properties and heat transfer behavior of the heat transfer oil–copper oxide (HTO–CuO) nanofluid in smooth tubes. Experimental Thermal and Fluid Science, 68:681–688, 2015.
[3] M.T.Naik, S.S. Fahad, L.S. Sundar, and M.K. Singh. Comparative study on thermal performance of twisted tape and wire coil inserts in turbulent flow using CuO/water nanofluid. Experimental Thermal and Fluid Science, 57:65–76, 2014.
[4] M.T. Naik, G.R. Janardana, and L.S. Sundar. Experimental investigation of heat transfer and friction factor with water–propylene glycol based CuO nanofluid in a tube with twisted tape inserts. International Communications in Heat and Mass Transfer, 46:13–21, 2013.
[5] J.J. Michael and S. Iniyan. Performance analysis of a copper sheet laminated photovoltaic thermal collector using copper oxide–water nanofluid. Solar Energy, 119:439–451, 2015.
[6] M. Bouhalleb and H. Abbassi. Natural convection in an inclined rectangular enclosure filled by CuO-H2O nanofluid, with sinusoidal temperature distribution. International Journal of Hydrogen Energy, 40(39):13676–13684, 2015.
[7] K. Goudarzi, E. Shojaeizadeh, and F. Nejati. An experimental investigation on the simultaneous effect of CuO-H2O nanofluid and receiver helical pipe on the thermal efficiency of a cylindrical solar collector. Applied Thermal Engineering, 73(1):1236–1243, 2014.
[8] Y. Abbassi, A.S. Shirani, and S. Asgarian. Two-phase mixture simulation of Al2O3/water nanofluid heat transfer in a non-uniform heat addition test section. Progress in Nuclear Energy, 83:356–364, 2015.
[9] H.K. Gupta, G.D. Agrawal, and J. Mathur. An experimental investigation of a low temperature Al2O3-H2O nanofluid based direct absorption solar collector. Solar Energy, 118:390–396, 2015.
[10] E. Shojaeizadeh, F. Veysi, and A. Kamandi. Exergy efficiency investigation and optimization of an Al2O3-water nanofluid based flat-plate solar collector. Energy and Buildings, 101:12–23, 2015.
[11] M.H. Esfe, A. Karimipour, W.-M. Yan, M. Akbari, M.R. Safaei, and M. Dahari. Experimental study on thermal conductivity of ethylene glycol based nanofluids containing Al2O3 nanoparticles. International Journal of Heat and Mass Transfer, 88:728–734, 2015.
[12] M.H. Esfe, S. Saedodin, M. Akbari, A. Karimipour, M. Afrand, S. Wongwises, M.R. Safaei, and M. Dahari. Experimental investigation and development of new correlations for thermal conductivity of cuo/eg–water nanofluid. International Communications in Heat and Mass Transfer, 65:47–51, 2015.
[13] L. S. Sundar, Md.H. Farooky, S.N. Sarada, and M.K. Singh. Experimental thermal conductivity of ethylene glycol and water mixture based low volume concentration of Al2O3 and CuO nanofluids. International Communications in Heat and Mass Transfer, 41:41–46, 2013.
[14] R.S. Khedkar, S.S. Sonawane, and K.L.Wasewar. Influence of CuO nanoparticles in enhancing the thermal conductivity of water and monoethylene glycol based nanofluids. International Communications in Heat and Mass Transfer, 39(5):665–669, 2012.
[15] M.N. Rashin and J. Hemalatha. A novel ultrasonic approach to determine thermal conductivity in CuO-ethylene glycol nanofluids. Journal of Molecular Liquids, 197:257–262, 2014.
[16] R. Karthik, R.H. Nagarajan, B. Raja, and P. Damodharan. Thermal conductivity of CuO-DI water nanofluids using 3-ω measurement technique in a suspended micro-wire. Experimental Thermal and Fluid Science, 40:1–9, 2012.
[17] S. Harikrishnan and S. Kalaiselvam. Preparation and thermal characteristics of CuO-oleic acid nanofluids as a phase change material. Thermochimica Acta, 533:46–55, 2012.
[18] M. Saeedinia, M.A. Akhavan-Behabadi, and P. Razi. Thermal and rheological characteristics of CuO-base oil nanofluid flow inside a circular tube. I nternational Communications in Heat and Mass Transfer, 39(1):152–159, 2012.
[19] M.-S. Liu, M.C.-C. Lin, I.-T. Huang, and C.-C. Wang. Enhancement of thermal conductivity with CuO for nanofluids. Chemical Engineering & Technology, 29(1):72–77, 2006.
[20] M.-S. Liu, M.C.-C. Lin, and C.-C. Wang. Enhancements of thermal conductivities with Cu, CuO, and carbon nanotube nanofluids and application of MWNT/water nanofluid on a water chiller system. Nanoscale Research Letters, 6(1):1–13, 2011.
[21] H.E. Patel, T. Sundararajan, and S.K. Das. An experimental investigation into the thermal conductivity enhancement in oxide and metallic nanofluids. Journal of Nanoparticle Research, 12(3):1015–1031, 2010.
[22] D.P. Kulkarni, R.S. Vajjha, D.K. Das, and D. Oliva. Application of aluminum oxide nanofluids in diesel electric generator as jacket water coolant. Applied Thermal Engineering, 28(14-15):1774–1781, 2008.
[23] M. Raja, R. Vijayan, S. Suresh, and R. Vivekananthan. Effect of heat transfer enhancement and NOx emission using Al2O3/water nanofluid as coolant in CI engine. Indian Journal of Engineering & Materials Sciences, 20:443–449, 2013.
[24] S.M. Peyghambarzadeh, S.H. Hashemabadi, S.M. Hoseini, and M.S. Jamnani. Experimental study of heat transfer enhancement using water/ethylene glycol based nanofluids as a newcoolant for car radiators. International Communications in Heat and Mass Transfer, 38(9):1283–1290, 2011.
[25] S. Suresh, M. Chandrasekar, and S.C. Sekhar. Experimental studies on heat transfer and friction factor characteristics of CuO/water nanofluid under turbulent flow in a helically dimpled tube. Experimental Thermal and Fluid Science, 35(3):542–549, 2011.
[26] M. Naraki, S.M. Peyghambarzadeh, S.H. Hashemabadi, and Y. Vermahmoudi. Parametric study of overall heat transfer coefficient of Cuo/water nanofluids in a car radiator. International Journal of Thermal Sciences, 66:82–90, 2013.
[27] B. Xiao, Y. Yang, and L. Chen. Developing a novel form of thermal conductivity of nanofluids with Brownian motion effect by means of fractal geometry. Powder Technology, 239:409–414, 2013.
[28] C. Sayin and M. Canakci. Effects of injection timing on the engine performance and exhaust emissions of a dual-fuel diesel engine. Energy Conversion and Management, 50(1):203–213, 2009.
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Authors and Affiliations

S. Senthilraja
1
KCK Vijayakumar
2
R. Gangadevi
3

  1. Faculty of Mechanical Engineering, Anna University, Chennai, India
  2. Department of Mechanical Engineering, Vivekanandha Institute of Engineering & Technology for Women, Tiruchengode, India
  3. Department of Mechatronics Engineering, SRM University, Chennai, India
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Abstract

The paper presents a methodology for creating dynamic characteristics of fuel consumption and intensity of emission of toxic components of exhaust gas. The source of data is the result of modal analysis of fuel consumption and emission intensity obtained from experimental drive tests. Two certified tests have been used: European NEDC and American Ff P- 75. A general algorithm for obtaining dynamic characteristics in the form of approximated functions is formulated on the basis of measured data. Examples of characteristics obtained for a real car with spark ignition engine are presented. The results obtained from experimental measurements and numerical simulations are compared and discussed.
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Authors and Affiliations

Krzysztof Brzozowski
Kazimierz Romaniszyn
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Abstract

Distribution of the exhaust gas temperature within the furnace of a grate boiler greatly depends on its operating parameters such as output. It has a considerably different character than temperature distributions in other types of boilers (with pulverised or fluidised bed), as it varies considerably across the chamber. Results presented in this paper have been obtained through research of a grate-fired hot water boiler with a nominal rating of some 30 MW. Measurements have been taken by introducing temperature sensors into prearranged openings placed in the boiler side walls. Investigation has been carried out for different output levels. Tests involved thermocouples in ceramic coating and aspirated thermocouples. The latter were used to eliminate influence of radiative heat transfer on measured results. Values obtained with both methods have been cross-checked.
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Authors and Affiliations

Piotr Krawczyk
Krzysztof Badyda
Jacek Szczygieł
Szczepan Młynarz
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Abstract

Using perforated tube in exhaust mufflers is known to improve transmission loss (TL) by improving their sound pressure level (SPL) at the orifice. The perforated tube should affect the muffler performance analogous to a shell-and-tube heat exchanger. To the authors’ knowledge, there are few previous assessments reported in literature of the effects that the perforated tube configuration has on acoustic response and pressure drop predicted. The effects of (i) the perforated tube length, (ii) the diameter of tube holes, and (iii) flow through perforated tube were investigated. To assess the perforated tube effect on flow, the SOLIDWORKS 2017 based on Computational Fluid Dynamics (CFD) tool was utilized using real walls approach model with a surface roughness of 0.5 micrometres (AISI 316 cold rolled stainless steel sheet (ss) Ra = 0:5 μm). Perforated tube was found to cause back pressure which may increase SPL about 10%.
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Bibliography

1. Cui F., Wang Y., Cai R.C. (2014), Improving muffler performance using simulation-based design, [in:] INTER-NOISE and NOISE-CON Congress and Conference Proceedings, 249(7): 1190–1194.
2. Demir A., Çinar Ö.Y. (2009), Propagation of sound in an infinite two-part duct carrying mean flow inserted axially into a larger infinite duct with wall impedance discontinuity, ZAMM – Journal of Applied Mathematics and Mechanics, 89(6): 454–465, doi: 10.1002/zamm.200800145.
3. Elsayed A., Bastien C., Jones S., Christensen J., Medina H., Kassem H. (2017), Investigation of baffle configuration effect on the performance of exhaust mufflers, Case Studies in Thermal Engineering, 10: 86–94, doi: 10.1016/j.csite.2017.03.006.
4. Ferziger J.H., Peric M. (2002), Computational Methods for Fluid Dynamics, 3rd ed., Springer, doi: 10.1007/978-3-642-56026-2.
5. Lee I., Selamet A. (2006), Impact of perforation impedance on the transmission loss of reactive and dissipative silencers, The Journal of the Acoustical Society of America, 120(6): 3706–3713, doi: 10.1121/1.2359703.
6. Mohamad B. (2019), Design and optimization of vehicle muffler using the Ffowcs Williams and Hawkings model, Machine Design, 11(3): 101–106, doi: 10.24867/MD.11.2019.3.101-106.
7. Mohamad B., Karoly J., Zelentsov A., Amroune S. (2020), A hybrid method technique for design and optimization of Formula race car exhaust muffler, International Review of Applied Sciences and Engineering, 11(2): 174–180, doi: 10.1556/1848.2020.20048.
8. Siano D. (2010), Three-dimensional/one-dimensional numerical correlation study of a three-pass perforated tube, Simulation Modelling Practice and Theory, 19(4): 1143–1153, doi: 10.1016/j.simpat.2010.04.005.
9. Sim H.J., Park S.G., Joe Y.G., Oh J.E. (2008), Design of the intake system for reducing the noise in the automobile using support vector regression, Journal of Mechanical Science and Technology, 22(6): 1121–1131, doi: 10.1007/s12206-008-0306-z.
10. Tiryakioglu B. (2020), Radiation of sound waves by a semi-infinite duct with outer lining and perforated end, Archives of Acoustics, 45(1): 77–84, doi: 10.24425/aoa.2020.132483.
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Authors and Affiliations

Barhm Mohamad
1
Jalics Karoly
1
Andrei Zelentsov
2
Salah Amroune
3

  1. Faculty of Mechanical Engineering and Informatics, University of Miskolc, Miskolc, Hungary
  2. Piston Engine Department, Bauman Moscow State Technical University, Moscow, Russia
  3. Université Mohamed Boudiaf, M’sila, Algérie
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Abstract

This paper presents a comparison of three surface condenser connection setups on the cooling water side. Four connections were considered, namely serial, mixed and two parallel ones. The analysis was conducted based on the calculated heat balances of proposed power unit for nominal and not nominal parameters for tested connections. Thermodynamic justification for the use of more complex configuration was verified. The exhaust steam pressure calculation was presented. Three methods of computing the heat transfer coefficient based on characteristic numbers, namely the Heat Exchange Institute (HEI) method, and the American Society of Mechanical Engineers (ASME) standard, were used. Calculation results were validated with the real data. The most accurate model was indicated and used in heat balance calculations. The assumptions and simplifications for the calculations are discussed. Examples of the calculation results are presented.

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Authors and Affiliations

Ewa Dobkiewicz-Wieczorek
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Abstract

Developed a method of a complex estimation of efficiency of the diesel particulate filter according to three criteria: the counting, the surface and the mass concentration of particulate matter considering their dispersion composition. The results of efficiency evaluation of a diesel particulate filter of freight car are presented using the proposed technique.
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Authors and Affiliations

A. Polivyanchuk
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Abstract

SI engines are highly susceptible to excess emissions when started at low ambient temperatures. This phenomenon has multiple air quality and climate forcing implications. Direct injection petrol engines feature a markedly different fuelling strategy, and so their emissions behaviour is somewhat different from indirect injection petrol engines. The excess emissions of direct injection engines at low ambient temperatures should also differ. Additionally, the direct injection fuel delivery process leads to the formation of PM, and DISI engines should show greater PM emissions at low ambient temperatures. This study reports on laboratory experiments quantifying excess emissions of gaseous and solid pollutants over a legislative driving cycle following cold start at a low ambient temperature for both engine types. Over the legislative cycle for testing at -7°C (the UDC), emissions of HC, CO, NOx and CO2 were higher when tested at -7°C than at 24°C. Massive increases in emissions of HC and CO were observed, together with more modest increases in NOx and CO2 emissions. Results from the entire driving cycle showed excess emissions in both phases (though they were much larger for the UDC). The DISI vehicle showed lower increases in fuel consumption than the port injected vehicles, but greater increases in emission of HC and CO. DISI particle number emissions increased by around 50%; DISI particle mass by over 600%. The observed emissions deteriorations varied somewhat by engine type and from vehicle to vehicle. Excesses were greatest following start-up, but persisted, even after several hundred seconds’ driving. The temperature of the intake air appeared to have a limited but significant effect on emissions after the engine has been running for some time. All vehicles tested here comfortably met the relevant EU limits, providing further evidence that these limits are no longer challenging and need updating.

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Authors and Affiliations

Piotr Bielaczyc
Andrzej Szczotka
Joseph Woodburn
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Abstract

Silicon – molybdenum cast iron commonly called SiMo due to its unique properties has becoming more and more interesting engineering material. The history and development of this alloy is relatively long but, due to the significant difficulties during the manufacturing process resulting in the lower final quality than expected, it has not been applied to often in practice. The biggest challenge is its brittleness as a result of the carbides precipitations. During last few years, thanks to the many important researches made and the general foundry technology development, the interest in SiMo iron has been rapidly growing, especially for the castings for heavy duty applications like corrosion, high temperature and wear abrasion resistant parts. In the article the heat treatment attempts to improve the microstructure of SiMo castings has been presented. The goal was to destroy or at least to refine and uniformly distribute the carbides precipitations to improve mechanical properties of the exhaust manifold castings for the cars. The experiments were carried out for the alloy contains approx. 4% Si, 1% Mo and 3.2%C. The range of the research included: hardness measuring, standard mechanical properties and microstructure for as-cast state and after that the subsequent heat treatment process with another properties check. The result of the heat treatment was the elimination of pearlite from the metal matrix. Moreover, the changes of the carbide molybdenum – rich phase morphology were observed. The dispersion of the carbides precipitations in the carbides area was observed. The experiments proved the possibility to control the microstructure and the mechanical properties of the SiMo castings by means of heat treatment but only to some extent.

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Authors and Affiliations

B. Cygan
M. Stawarz
J. Jezierski
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Abstract

In some areas of the United States (US), asthma prevalence has reached historically unprecedented highs. Three peer-reviewed studies in New York City found prevalence rates among children from 25% to 39%. That is not true in all places. For example, prevalence in Miami, Florida, was estimated to be only 6-10%. A recent study in major cities in Georgia found only 8.5%. One study in California found asthma prevalence was unrelated to local concentrations of criterion pollutants. In the US, all criterion pollutants, including PM2.5, show a downward trend over the last two decades. These facts argue against any significant influence of criterion pollutants in this crisis.These facts suggest that an unrecognized ambient pollutant may be the cause. One important study in southern California in mid-summer measured pulmonary function in children as it was related to outdoor ozone pollution. They found a negative association; higher levels of ozone were associated with improved respiratory function. We call this a "Paradoxical Ozone Association" (POA). Further evidence for a POA appears in seven other studies in Los Angeles, London, Scotland, and southeastern Canada.One plausible explanation for these observations would be the production of methyl nitrite (MN) as an exhaust product of MTB E in gasoline. Unlike ozone, MN is rapidly destroyed by sunlight. All of the POA studies were done in regions with significant methyl ether in gasoline. This explanation is strengthened by the observation that a POA has not been seen in regions without ether in gasoline.A previous A WMA paper proposed a plausible chemical model predicting that MTBE in gasoline will create MN in the exhaust. MN is highly toxic and closely related alkyl nitrites are known to induce respiratory sensitivity in humans. Funding to measure MN has not been available
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Authors and Affiliations

Peter M. Joseph
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Abstract

This article deals with the rise in the Polish literature of 1970s of a new type of biographical novel, associated with the fi rst post-war generation of writers like Bohdan Zadura, Julian Kornhauser, Adam Zagajewski, Henryk Lothamer, Stanisław Piskor and Donat Kirsch. Their work is subsumed here under the label ‘new fi ction’ primarily because of its literary context, i.e. the late-modern fears and uncertainties culminating in the assumption that literature reached the state of exhaustion. The article argues that the ‘new fi ction’ acquired its distinctive character from a preoccupation with the biographical narrative and a sense of generational identity. The writers who defi ned themselves in these generational terms saw their prospect of following their aspirations and building up authentic lives weighed down by the constricting realities, and, as the article claims, resigned themselves – at best not entirely – to this sad conclusion.

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Authors and Affiliations

Przemysław Kaliszuk

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