scholarly journals The Dependence of Selected Technical and Combustion Characteristics of Fire on Moisture Levels in Alternative Fuels

2014 ◽  
Vol 9 (1) ◽  
pp. 25-30
Author(s):  
Martin Kulich
Keyword(s):  
Alternative Fuels ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Final Part ◽  
Operational Risks ◽  
Operational Safety ◽  
The Subject

Abstract The subject of this paper is to analyse the influence of moisture on selected technical and combustion characteristics of alternative fuels. The analyses are conducted on the basis of analyses of samples of alternative fuels simulating states of the fuel in expected operating conditions, focusing on the identification of potential operational risks. The final part consists of a set of recommended measures to ensure the operational safety of the practical use of alternative fuels based on the results of the analysis.

scholarly journals Numerical Investigations of Micro-Scale Diffusion Combustion: A Brief Review

2019 ◽  
Vol 9 (16) ◽  
pp. 3356 ◽  
Author(s):  
P. R. Resende ◽  
Mohsen Ayoobi ◽  
Alexandre M. Afonso
Keyword(s):  
Alternative Fuels ◽  
Numerical Models ◽  
Scientific Progress ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Critical Parameters ◽  
Diffusion Combustion ◽  
Great Opportunity ◽  
Numerical Investigations ◽  
Numerical Approaches

With the increasing global concerns about the impacts of byproducts from the combustion of fossil fuels, researchers have made significant progress in seeking alternative fuels that have cleaner combustion characteristics. Such fuels are most suitable for addressing the increasing demands on combustion-based micro power generation systems due to their prominently higher energy density as compared to other energy resources such as batteries. This cultivates a great opportunity to develop portable power devices, which can be utilized in unmanned aerial vehicles (UAVs), micro satellite thrusters or micro chemical reactors and sensors. However, combustion at small scales—whether premixed or non-premixed (diffusion)—has its own challenges as the interplay of various physical phenomena needs to be understood comprehensively. This paper reviews the scientific progress that researchers have made over the past couple of decades for the numerical investigations of diffusion flames at micro scales. Specifically, the objective of this review is to provide insights on different numerical approaches in analyzing diffusion combustion at micro scales, where the importance of operating conditions, critical parameters and the conjugate heat transfer/heat re-circulation have been extensively analyzed. Comparing simulation results with experimental data, numerical approaches have been shown to perform differently in different conditions and careful consideration should be given to the selection of the numerical models depending on the specifics of the cases that are being modeled. Varying different parameters such as fuel type and mixture, inlet velocity, wall conductivity, and so forth, researchers have shown that at micro scales, diffusion combustion characteristics and flame dynamics are critically sensitive to the operating conditions, that is, it is possible to alter the flammability limits, control the flame stability/instability or change other flame characteristics such as flame shape and height, flame temperature, and so forth.

Combustion Characteristics of a Swirled Burner Fueled With Waste Cooking Oil

2015 ◽  
Author(s):  
Ahmed Abdelgawad ◽  
Ahmed Emara ◽  
Mohamed Gad ◽  
Ahmed Elfatih
Keyword(s):  
Alternative Fuels ◽  
Fossil Fuels ◽  
Chemical Properties ◽  
Waste Cooking Oil ◽  
Diesel Oil ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Exhaust Gas ◽  
Gas Temperature ◽  
Cooking Oil

Due to the intensive and extensive consumption of fossil fuels in all life sectors such as transportation, power generation, industrial processes, and residential consumption lead to find other new alternative fuels should be the target to cover this fuel demand. Fossil fuel resources are considered non-renewable sources and they will be depleted in the near future. In addition to its environmental impact which causes global warming, harmful exhaust emissions, and its price instability. Waste cooking oil (WCO) was considered as one of these alternative fuels and additives which will provide the industry with low price fuel and may solve the problem of getting rid of waste cooking oil. The present work demonstrated a comparative study for combustion characteristics between light diesel oil (LDO) and waste cooking oil in a swirled oil burner. Waste cooking oil was used directly as a fuel inside a cylindrical combustor using a swirled liquid oil burner at different operating conditions. Waste cooking oil was preheated to 90 °C before entering oil burner to decrease its viscosity and near to light diesel oil. Physical and chemical properties of waste cooking oil were measured and characterized according to ASTM standards. Combustion characteristics of this swirled oil burner using waste cooking oil and light diesel oil were experimentally investigated. Axial and radial inflame temperatures; exhaust gas emissions concentrations and combustor efficiency were analyzed. The experimental results showed that the increase of primary air pressure led to increase in exhaust gas temperature for LDO and WCO. CO2 emissions values for LDO increased compared to WCO. Hydrocarbons a emissions for WCO were higher than LDO. Percentage of heat transferred to the combustor wall increased for WCO compared to LDO. Increase of radial inflame temperature of WCO compared to LDO was due to the increase in heat release at high equivalence ratio. Waste cooking oil tended to produce luminous flames compared to diesel oil due to higher carbon content in its chemical composition.

A Rhetorics of the Word

2019 ◽  
Author(s):  
George Pattison
Keyword(s):  
Political Discourse ◽  
Philosophical Tradition ◽  
Final Part ◽  
Communications Technology ◽  
Christian Life ◽  
Call And Response ◽  
Hermann Broch ◽  
The Subject ◽  
The Impact

A Rhetorics of the Word is the second volume of a three-part philosophy of Christian life. It approaches Christian life as expressive of a divine calling or vocation. The word Church (ekklesia) and the role of naming in baptism indicate the fundamental place of calling in Christian life. However, ideas of vocation are difficult to access in a world shaped by the experience of disenchantment. The difficulties of articulating vocation are explored with reference to Weber, Heidegger, and Kierkegaard. These are further connected to a general crisis of language, manifesting in the degradation of political discourse (Arendt) and the impact of new communications technology on human discourse. This impact can be seen as reinforcing an occlusion of language in favour of rationality already evidenced in the philosophical tradition and technocratic management. New possibilities for thinking vocation are pursued through the biblical prophets (with emphasis on Buber’s and Rosenzweig’s reinterpretation of the call of Moses), Saint John, and Russian philosophies of language (Florensky to Bakhtin). Vocation emerges as bound up with the possibility of being name-bearers, enabling a mutuality of call and response. This is then evidenced further in ethics and poetics, where Levinas and Hermann Broch (The Death of Virgil) become major points of reference. In conclusion, the themes of calling and the name are seen to shape the possibility of love—the subject of the final part of the philosophy of Christian life: A Metaphysics of Love.

scholarly journals Ethanol/Gasoline Blends as Alternative Fuel in Last Generation Spark-Ignition Engines: A Review on CO and HC Engine Out Emissions

Energies ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 4034
Author(s):  
Paolo Iodice ◽  
Massimo Cardone
Keyword(s):  
Physicochemical Properties ◽  
Alternative Fuels ◽  
Experimental Studies ◽  
Alternative Fuel ◽  
Exhaust Emissions ◽  
Spark Ignition ◽  
Operating Conditions ◽  
Spark Ignition Engine ◽  
Spark Ignition Engines ◽  
The Impact

Among the alternative fuels existing for spark-ignition engines, ethanol is considered worldwide as an important renewable fuel when mixed with pure gasoline because of its favorable physicochemical properties. An in-depth and updated investigation on the issue of CO and HC engine out emissions related to use of ethanol/gasoline fuels in spark-ignition engines is therefore necessary. Starting from our experimental studies on engine out emissions of a last generation spark-ignition engine fueled with ethanol/gasoline fuels, the aim of this new investigation is to offer a complete literature review on the present state of ethanol combustion in last generation spark-ignition engines under real working conditions to clarify the possible change in CO and HC emissions. In the first section of this paper, a comparison between physicochemical properties of ethanol and gasoline is examined to assess the practicability of using ethanol as an alternative fuel for spark-ignition engines and to investigate the effect on engine out emissions and combustion efficiency. In the next section, this article focuses on the impact of ethanol/gasoline fuels on CO and HC formation. Many studies related to combustion characteristics and exhaust emissions in spark-ignition engines fueled with ethanol/gasoline fuels are thus discussed in detail. Most of these experimental investigations conclude that the addition of ethanol with gasoline fuel mixtures can really decrease the CO and HC exhaust emissions of last generation spark-ignition engines in several operating conditions.

Effects of Air Temperature on Combustion Characteristics of LPG Diffusion Flame

2020 ◽  
Vol 1008 ◽  
pp. 128-138
Author(s):  
Ahmed M. Salman ◽  
Ibrahim A. Ibrahim ◽  
Hamada M. Gad ◽  
Tharwat M. Farag
Keyword(s):  
Air Temperature ◽  
Diffusion Flame ◽  
Nitrogen Addition ◽  
Flame Length ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Low Oxygen ◽  
Air Temperatures ◽  
Air Stream ◽  
Wide Range

In the present study, the combustion characteristics of LPG gaseous fuel diffusion flame at elevated air temperatures were experimentally investigated. An experimental test rig was manufactured to examine a wide range of operating conditions. The investigated parameters are the air temperatures of 300, 350, 400, 450, and 500 K with constant percentage of nitrogen addition in combustion air stream of 5 % to give low oxygen concentration of 18.3 % by mass at constant air swirl number, air to fuel mass ratio, and thermal load of 1.5, 30, and 23 kW, respectively. The gaseous combustion characteristics were represented as axial and radial temperatures distributions, temperatures gradient, visible flame length and species concentrations. The results indicated that as the air temperature increased, the chemical reaction rate increased and flame volume decreased, the combustion time reduced leading to a reduction in flame length. The NO concentration reaches its maximum values near the location of the maximum centerline axial temperature. Increasing the combustion air temperature by 200 K, the NO consequently O2 concentrations are increased by about % 355 and 20 % respectively, while CO2 and CO concentrations are decreased by about % 21 and 99 % respectively, at the combustor end.

Ethers and esters as alternative fuels for internal combustion engine: A review

2021 ◽  
pp. 146808742110464
Author(s):  
Yang Hua
Keyword(s):  
Alternative Fuels ◽  
Combustion Engine ◽  
Combustion Process ◽  
Pressure Rise ◽  
Engine Performance ◽  
Internal Combustion ◽  
Operating Conditions ◽  
Future Research ◽  
Particulate Emissions ◽  
Ic Engine

Ether and ester fuels can work in the existing internal combustion (IC) engine with some important advantages. This work comprehensively reviews and summarizes the literatures on ether fuels represented by DME, DEE, DBE, DGM, and DMM, and ester fuels represented by DMC and biodiesel from three aspects of properties, production and engine application, so as to prove their feasibility and prospects as alternative fuels for compression ignition (CI) and spark ignition (SI) engines. These studies cover the effects of ether and ester fuels applied in the form of single fuel, mixed fuel, dual-fuel, and multi-fuel on engine performance, combustion and emission characteristics. The evaluation indexes mainly include torque, power, BTE, BSFC, ignition delay, heat release rate, pressure rise rate, combustion duration, exhaust gas temperature, CO, HC, NOx, PM, and smoke. The results show that ethers and esters have varying degrees of impact on engine performance, combustion and emissions. They can basically improve the thermal efficiency of the engine and reduce particulate emissions, but their effects on power, fuel consumption, combustion process, and CO, HC, and NOx emissions are uncertain, which is due to the coupling of operating conditions, fuel molecular structure, in-cylinder environment and application methods. By changing the injection strategy, adjusting the EGR rate, adopting a new combustion mode, adding improvers or synergizing multiple fuels, adverse effects can be avoided and the benefits of oxygenated fuel can be maximized. Finally, some challenges faced by alternative fuels and future research directions are analyzed.

scholarly journals Emissions and In-Cylinder Combustion Characteristics of Fischer-Tropsch and Conventional Diesel Fuels in a Modern CI Engine

2005 ◽  
Author(s):  
Alexander G. Sappok ◽  
Jeremy T. Llaniguez ◽  
Joseph Acar ◽  
Victor W. Wong
Keyword(s):  
Combustion Characteristics ◽  
Operating Conditions ◽  
Fuel Properties ◽  
Emissions Reduction ◽  
Cylinder Pressure ◽  
Fischer Tropsch ◽  
Diesel Fuels ◽  
Ultra Low Sulfur Diesel ◽  
Low Sulfur ◽  
Detailed Chemical

Derived from natural gas, coal, and even biomass Fischer-Tropsch (F-T) diesel fuels have a number of very desirable properties. The potential for emissions reduction with F-T diesel fuels in laboratory engine tests and on-road vehicle tests is well documented. While a number of chemical and physical characteristics of F-T fuels have been attributed to the observed reduction in emissions, the actual effects of both the fuel properties and in-cylinder combustion characteristics in modern diesel engines are still not well understood. In this study a 2002, six-cylinder, 5.9 liter, Cummins ISB 300 diesel engine, outfitted with an in-cylinder pressure transducer. was subjected to a subset of the Euro III 13-mode test cycle under steady-state operating conditions. Emissions and in-cylinder pressure measurements were conducted for neat F-T diesel, low sulfur diesel (LSD), ultra-low sulfur diesel (ULSD), and a blend of FT/LSD. In addition, a detailed chemical analysis of the fuels was carried out. The differences in the measured combustion characteristics and fuel properties were compared to the emissions variations between the fuels studied, and an explanation for the observed emissions behavior of the fuels was developed.

Application of Moving Car Observer Method for Measuring Free Flow Speed on Two-lane Highways

2014 ◽  
Vol 69 (6) ◽  
Author(s):  
Othman Che Puan ◽  
Muttaka Na’iya Ibrahim ◽  
Usman Tasiu Abdurrahman
Keyword(s):  
Field Measurement ◽  
Flow Speed ◽  
Operating Conditions ◽  
Free Flow ◽  
Geometric Features ◽  
Highway Capacity ◽  
Highway Capacity Manual ◽  
Free Flow Speed ◽  
The Subject ◽  
Low Traffic

There exists a need to evaluate the performance indicator that reflects the current level of service (LOS) of the subject facility to justify any decision making on expenditures to be made for improving the performance level of a road facility. Free-flow speed (FFS) is one of the key parameters associated with LOS assessment for two-lane highways. Application of a more realistic approach for assessing road’s performance indicators would result in better estimates which could in turn suggest the most appropriate decision to be made (for situations where upgrading is needed); especially, in terms of finance, materials and human resources. FFS is the driver’s desired speed at low traffic volume condition and in the absence of traffic control devices. Its estimation is significant in the analysis of two-lane highways through which average travel speed (ATS); an LOS indicator for the subject road class is determined. The Highway Capacity Manual (HCM) 2010 offers an indirect method for field estimation of FSS based on the highway operating conditions in terms of base-free-flow-speed (BFFS). It is however, recommended by the same manual that direct field FSS measurement approach is most preferred. The Malaysian Highway Capacity Manual (MHCM) established a model for estimating FFS based on BFFS, the geometric features of the highway and proportion of motorcycles in the traffic stream. Estimating FFS based on BFFS is regarded as an indirect approach which is only resorted to, if direct field measurement proved difficult or not feasible. This paper presents the application of moving car observer (MCO) method for direct field measurement of FFS. Data for the study were collected on six segments of two-lane highways with varying geometric features. FFS estimates from MCO method were compared with those based on MHCM model. Findings from the study revealed that FFS values from MCO method seem to be consistently lower than those based on MHCM model. To ascertain the extent of the difference between the FFS values from the two approaches, student t-statistics was used. The t-statistics revealed a P–value of less than 0.05 (P < 0.05) which implies that there is a statistically significant difference between the two sets of data. Since MCO method was conducted under low traffic flow (most desired condition for field observation), it can be suggested that MCO estimates of FFS represent the actual scenario. A relationship was therefore developed between the estimates from the two methods. Thus, if the MHCM model is to be applied, the measured value needs to be adjusted based on the relationship developed between the two approaches.

Combustion Characteristics of Small Size Gas Turbine Combustor Fueled by Biomass Gas Employing Flameless Combustion

2007 ◽  
Author(s):  
Masato Hiramatsu ◽  
Yoshifumi Nakashima ◽  
Sadamasa Adachi ◽  
Yudai Yamasaki ◽  
Shigehiko Kaneko
Keyword(s):  
Gas Turbine ◽  
Combustion Efficiency ◽  
Combustion Characteristics ◽  
Operating Conditions ◽  
Nox Emissions ◽  
Gas Turbine Combustor ◽  
Flameless Combustion ◽  
Engine Exhaust ◽  
Micro Gas Turbine

One approach to achieving 99% combustion efficiency (C.E.) and 10 ppmV or lower NOx (at 15%O2) in a micro gas turbine (MGT) combustor fueled by biomass gas at a variety of operating conditions is with the use of flameless combustion (FLC). This paper compares experimentally obtained results and CHEMKIN analysis conducted for the developed combustor. As a result, increase the number of stage of FLC combustion enlarges the MGT operation range with low-NOx emissions and high-C.E. The composition of fuel has a small effect on the characteristics of ignition in FLC. In addition, NOx in the engine exhaust is reduced by higher levels of CO2 in the fuel.

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