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Investigating Combustion Process of N-Butanol-Diesel Blends in a Diesel Engine with Variable Compression Ratio

Kristóf Lukács György Szabados Ákos Bereczky

Publication Name: Clean Technologies

Publication Date: 2021-09-01

Volume: 3

Issue: 3

Page Range: 618-628

Description:

The search for alternative fuels for internal combustion engines is ongoing. Among the alternatives, plant-based fuels can also be mentioned. Alcohol is not a common fuel for diesel engines because the physical and chemical properties of the alcohols are closer to those of gasoline. In our research, the combustion properties of diesel-n-butanol mixtures have been investigated to obtain results on the effect of butanol blending on combustion. Among the combustion properties, ignition delay, in-cylinder pressure, and heat release rate can be mentioned. They have been observed under different compression conditions on an engine on which the compression ratio can be adjusted. The method used was a quite simple one, so the speed of the engine was set to a constant 900 rpm without load, while three compression ratios (19.92, 15.27, and 12.53) were adjusted with a fuel flow rate of 13 mL/min and the pre-injection angle of 18◦ BTDC. Blending butanol into the investigated fuel does not significantly affect maximal values of indicated pressure, while much more effect on the pressure rising rate can be detected. Furthermore, heat release rate and ignition delay increased at every compression ratio investigated. Despite the low blending rates of butanol in the mixtures, butanol significantly affects the combustion parameters, especially at high compression ratios.

Open Access: Yes

DOI: 10.3390/cleantechnol3030037

Carbon accounting measurement with digital non-financial corporate reporting and a comparison to european automotive companies statements

Cecília Szigeti Árpád Tóth Alex Suta

Publication Name: Energies

Publication Date: 2021-09-01

Volume: 14

Issue: 18

Page Range: Unknown

Description:

The regulatory environment for both sustainability and financial reporting is changing as standardisation and digital reporting (e.g., XBRL) are gaining traction within regulators. The measurement methodology and mandatory information content of disclosures are yet to be decided for corporate CO2 reporting by EU regulators and standard-setting organisations. In our study, we reviewed the sustainability reports of three leading German automotive groups by revenue for the period 2016–2020 as a case study. The research methodology was carried out with text-mining-aided content analysis to provide a collection of sustainability standards (GRI and SASB) in the evaluation of emissions reporting. As an addition to prior literature, conditions of relevance and clarity regarding published information were introduced in the evaluation process of compliance to CO2 disclosures. Companies by reporting practice were assigned to different stages of carbon management and actual emissions were evaluated. In the conclusions, discussion of the reliability of reported sustainability information, the applicability of digital reporting is provided through regional perspectives. We found that although analytical methods are available to assess the level of corporate carbon management, their usefulness is limited if the data are not reliable. Significant progress can be expected from analyses using standardised, comparable corporate carbon data.

Open Access: Yes

DOI: 10.3390/en14185607

Application of Bivariate Extreme Value models to describe the joint behavior of temporal and speed related surrogate measures of safety

Attila Borsos

Publication Name: Accident Analysis and Prevention

Publication Date: 2021-09-01

Volume: 159

Issue: Unknown

Page Range: Unknown

Description:

Limitations of historical crash data and the advantages of surrogate measures of safety have already been stressed by various authors. To describe nearness-to-collision, mostly time-based indicators are applied, and there is a consensus among researchers that speed-related indicators are needed to account for the severity dimension. There have been attempts to fit bivariate Extreme Value models to predict the number of crashes, however modeling crash frequency together with severity has received much less attention. The aim of this paper is to apply Extreme Value models to various pairs of temporal and speed-related indicators in order to investigate the dependence structure between them as well as to construct probability based risk levels and examine them in relation to severity levels. Bivariate threshold excess models were fitted to a dataset of left-turning and straight moving vehicle interactions recorded in a signalized intersection. The dependence structure between variable pairs were thoroughly investigated; it was concluded that temporal and speed related indicators were found independent, which means that road users getting close to each other in time does not necessarily come with high speeds. Therefore these indicators should be combined in order to properly predict severity; a temporal indicator on its own is not enough to make inferences about the severity of events. Using the calculated joint probability of events risk levels were constructed illustrating the events of equal probability.

Open Access: Yes

DOI: 10.1016/j.aap.2021.106274

Big data for sustainable agri‐food supply chains: a review and future research perspectives

Suhaiza Zailani Abderahman Rejeb Karim Rejeb

Publication Name: Journal of Data Information and Management

Publication Date: 2021-09-01

Volume: 3

Issue: 3

Page Range: 167-182

Description:

Research on agri-food supply chains (AFSCs) has attracted significant attention in recent years due to the challenges associated with sustainably feeding the global population. The purpose of this study is to review the potentials of big data for sustainable AFSCs. One hundred twenty-eight (128) journal articles were selected to identify how big data can contribute to the sustainable development of AFSCs. As part of our focus, a framework was developed based on the conceptualization of AFSCs in the extant literature to analyse big data research in the context of AFSCs and to provide insights into the potentials of the technology for agri-food businesses. The findings of the review indicate that there is a noticeable growth in the number of studies addressing the applications of big data for AFSCs. The potentials of big data for AFSC sustainability were synthesized in a summary framework, highlighting the primary resources and activities that are ready for improvement with big data. These include soil, water, crop and plant management, animal management, waste management and traceability management. The challenges of big data integration in AFSCs, the study’s implications, contributions, and the future research directions are highlighted in detail.

Open Access: Yes

DOI: 10.1007/s42488-021-00045-3

Comprehensive assessment of oil degradation patterns in petrol and diesel engines observed in a field test with passenger cars – Conventional oil analysis and fuel dilution

Charlotte Besser András Lajos Nagy Adam Agocs J. Rohde-Brandenburger József Perger Michael Schandl Zsolt Tabakov Nicole Dörr

Publication Name: Tribology International

Publication Date: 2021-09-01

Volume: 161

Issue: Unknown

Page Range: Unknown

Description:

Requirements for modern internal combustion engines are lower emissions, higher power density and longer maintenance intervals. These trends increase the demands on engine components, including lubricants. In a field study of petrol and diesel vehicles, oil condition of 47 engine oils from 12 vehicles are correlated with fresh oil properties and operating conditions, i.e., trip length and speed. Long-range petrol vehicles displayed accelerated chemical oil degradation compared to diesel vehicles. An explanation for this behaviour is assumed to be the difference air-to-fuel ratio. Short-range petrol vehicles showed an even faster oil degradation and significant changes in oil viscosity due to fuel dilution. Diesel vehicles exhibited higher soot loading and more pronounced engine wear indicated by iron content in the oils.

Open Access: Yes

DOI: 10.1016/j.triboint.2021.107079

Advantages and limitations of using foamed bitumen

A. Saleh László Gáspár

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-08-25

Volume: 14

Issue: 3

Page Range: 300-314

Description:

Foamed asphalt refers to a bituminous mixture of road-building aggregates and foamed bitumen, produced by a cold mix process. There are a lot of related issue that has not been sufficiently investigated so far. It is worthwhile to overview the main theoretical and practical results in the field in several countries including those of the authors of the paper. It is clear that the foamed asphalt is usually characterized by high quality and reasonable cost, can be used in cold road pavement rehabilitation, in addition to it the technique is environ-mentally friendly preserving natural resources. Using foamed bitumen reduces the emissions of carbon dioxide and gases resulting from combustion, especially when it is used as a cold rehabilitation binder and mixed with re-claimed asphalt pavement materials.

Open Access: Yes

DOI: 10.14513/actatechjaur.00587

Study the effect of Heavy Oil Fuel Ash on the geotechnical properties of clay soil

Ali Tawalo Rami Ousta

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-08-25

Volume: 14

Issue: 3

Page Range: 270-280

Description:

Power stations are widely spread in Arabic Syrian Republic, unlike most of power stations in the world that work by using coal as the operating fuel, most of Syrian power stations depend on the heavy fuel oil to generate electricity. Although there are a lot of studies about use of the fly ash produced from burning coal, the fly ash resulted by using heavy fuel oil as an operating material for the power stations had less attention. This paper aims to study the effect of this type of fly ash on the geotechnical properties of the clay soil and comparison it with the effect of fly ash resulted by power stations that use the coal. Two percentages of heavy oil fuel ash were mixed with the soil 5% and 10% of the dry soil weight with two curing periods 7 and 28 days. The results indicated that adding heavy oil fuel ash to the soil will decrease the cohesion in addition to increase the internal friction angle. There is not clear effect of the curing periods and the increase in the percentage of fly ash on the Atterberg limits.

Open Access: Yes

DOI: 10.14513/actatechjaur.00607

Special reinforcement solutions of railway permanent ways’ soil substructures

Muayad Habashneh

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-08-25

Volume: 14

Issue: 3

Page Range: 339-363

Description:

This mini review aims to summarize relevant international publications. Thus, based on this, giving a comprehensive review about the reinforcement solutions of permanent ways' soil substructure. Generally, the core weakness of soil is its inadequacy to resist tensile stresses. The main target of strengthening the soil is to enhance the engineering characteristics of the soil to build up specific parameters such as shear strength, compressibility, density, and hydraulic conductivity. In addition, special reinforcement techniques of railway permanent ways' soil substructures will be considered in this paper due to the increasing demand of improving railways and rehabilitation process. The main findings of this study that there are a lot of special reinforcement techniques which can be considered as effective solution for soil stabilization such as geosynthetic reinforcement.

Open Access: Yes

DOI: 10.14513/actatechjaur.00612

Review of materials used for ballast reinforcement

Majd Ahmad

Publication Name: Acta Technica Jaurinensis

Publication Date: 2021-08-25

Volume: 14

Issue: 3

Page Range: 315-338

Description:

This mini review summarizes the most recent research in ballast reinforcement. Several materials are being used for the purpose of improving the ballast layer in railways, including geosynthetics, rubber sheets and binding agents. Such methods of reinforcement have proven to be beneficial for increasing the strength, stiffness, and resilience of the ballast layer in addition to reducing settlement, breakage, degradation, and maintenance cost and frequency. Latest studies try to find the best types, placement, and combination of geosynthetics to achieve the highest strength and resistance, in addition to obtaining the optimum percentage of binding agents and methods of applying them in order to discover the most effective binder that achieves the most improvement to the mechanical properties of the layer for a reasonable price. An overview of the recent tests conducted to study the reinforced ballast layer and their results is presented in this paper, as well as an overall evaluation of the implementation of these reinforcement methods in railways.

Open Access: Yes

DOI: 10.14513/actatechjaur.00610