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Effect of ignition timing on emissions of spark ignition engine using E85 fuel
2014
Gailis, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pirs, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
This experimental study assesses the influence of ignition timing on emissions from a production four cylinder port injection spark ignition engine. The aim of this research was to evaluate the necessity of ignition timing correction when the regular gasoline vehicle is being adapted for the use of E85 fuel. Tests were conducted in the Alternative Fuels Research Laboratory of Latvia University of Agriculture in December 2013. The engine was fuelled with the ethanol-gasoline blend E85 or the commercial gasoline A95. The engine was tested within a vehicle in a chassis dynamometer in steady state conditions, which resemble driving at 50 km hE-1 and 90 km hE-1. The original engine control unit was replaced with a programmable one. Engine-out and tailpipe exhaust gas samples were taken and analysed with a FTIR-type analyser AVL SESAM. Carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxides (NOx), acetaldehyde and unburned ethanol emission volumetric share is presented. CO, HC and acetaldehyde emissions were not affected by variation of the ignition timing within the tested range. NOx and ethanol emissions were reduced with the ignition timing retard. The emissions of CO, HC and NOx were reduced, when the engine was fuelled with the E85 fuel, comparing with the gasoline use. Ignition timing, optimized for the gasoline, was found suitable for the E85 fuel from the emission analyses point.
Afficher plus [+] Moins [-]Experimental investigation of fuel conversion adapter using bioethanol and gasoline blends
2013
Gailis, M., Latvia Univ. of Agriculture, Jelgava (Latvia) | Pirs, V., Latvia Univ. of Agriculture, Jelgava (Latvia)
The paper contains description of the working principles and evaluation of the operational parameters of the commercially available fuel conversion adapter, intended to adapt gasoline fuelled spark ignition (SI) engine for use of high ethanol content blended fuel, known as E85. Commercially available gasoline and E85 fuel were used as test fuels. Production automobile, equipped with 1.8 litre 4 cylinder SI port fuel injection (PFI) engine was tested on the roll-type eddy-current chassis dynamometer in wide open throttle (WOT) constant speed mode. High precision fuel consumption measurement system AVL KMA Mobile was used. Engine operating parameters, used for evaluation of the efficiency of the fuel conversion adapter was engine torque (T), engine brake power (Pb ), air/fuel equivalence ratio (λ), specific fuel consumption (SFC) and engine thermal efficiency (ηt ). Analysis of engine operational parameters showed successful operation of fuel conversion adapter with E85 fuel, resulting in increase of engine peak torque by 4.4%, increase of energy efficiency in whole tested engine speed range up to 6.1% but increase of specific fuel consumption by approximately 22%, when compared with the gasoline use.
Afficher plus [+] Moins [-]Computational fluid dynamics pressure wave and flow rate analysis of intake runner design in internal combustion engine
2018
Banis, K., Latvia Univ. of Life Sciences and Technologies, Jelgava (Latvia)
This paper investigates the effect of intake runner design on pressure wave propagation and reflection in sparkignited internal combustion (IC) engine. These events are known to leave a noticeable influence on the overall engine performance therefore the aim of this study is to evaluate how changes in intake runner geometry affect pressure oscillations and volume flow rate. Time-dependent computational fluid dynamics (CFD) analysis was carried out to determine how these changes affect the pressure oscillations during a full engine cycle at constant crankshaft speed. Steady state CFD analysis at constant pressure differential was carried out to evaluate the effect on volume flow rate. The simulations were carried out in SolidWorks Flow Simulation environment. Honda CRF450R motorcycle engine was used to define the initial conditions and basic intake runner design. Intake air speed at port entrance cross-section was calculated based on engine parameters and operating speed. The average pressure values with respect to physical time were measured and graphed across the intake port opening cross-section. Six different intake runner designs were compared. It was concluded that the runner taper angle has influence on pressure wave-length but internal geometry (steps, curvature and taper angle) has influence on volume flow rate. It was observed that cylindrical intake runner design produced an increase in pressure wave-length but a cylindrical section of the intake runner with a stepped transition to tapered extension produced a slight increase in pressure wave amplitude.
Afficher plus [+] Moins [-]Data acquisition system for vehicle engine sensors: A review
2024
Melders, Lauris | Smigins, Ruslans | Birkavs, Aivars
Monitoring the operation of car engines using a smartphone and cloud services is a concept that falls within the field of intelligent vehicle technologies. Using information collection system, vehicle fleet companies can effectively manage the usage of their vehicles, minimizing investment and maintenance costs, preventing accidents and failures, identifying poor driving behaviour among employees, and reducing expenses associated with fuel, tires, and other resources. This approach involves collecting real-time data from the vehicle engine sensors, transferring data to the cloud via a smartphone, and then using cloud services to analyse and manage the information, making it understandable in a simple way. This review reflects on the working efficiency of internal combustion engines and the reduction of pollution to the environment, also gathers existing literature to gain insights into vehicle sensor data acquisition technology and systems in the automotive industry identifying gaps in current knowledge and provide a conceptual framework for next practical research in this field. After explaining the general idea of logistics tasks in technology development, various sensors and their methods are associated with engine properties are introduced. The research results show that most articles are about data acquisition systems from different systems. They can provide convenience and flexibility for users, allowing them to easily access and adjust settings on-the-go, enabling real-time monitoring and adjustment of engine performance, helping users optimize efficiency and performance based on their specific needs and preferences.
Afficher plus [+] Moins [-]Hydroxy gas as an additive for improvement of exhaust emissions of internal combustion engines — a review
2023
Amatnieks, Kārlis | Birkavs, Aivars | Šmigins, Ruslans
Lowering emissions expelled from internal combustion engines has been the focus of researchers worldwide. Adding hydroxy gas to current internal combustion engines can be an effective way of lowering CO2, CO, HC and particle emissions, as well as improve combustion. Because of this, a review of previously conducted research on the addition of hydroxy gas to different internal combustion engines has been produced. During this review, it was concluded that addition of hydroxy gas can be an effective way of lowering fuel consumption and CO, CO2 and HC emissions in petrol engines, as well as fuel consumption and CO and HC emissions in diesel engines.
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