Wyniki wyszukiwania - BazTech

1

Fluid dynamic and acoustic optimization methodology of a formula-student race car engine exhaust system using multilevel numerical CFD models

Mohamad Barhm, Ali Mohammed Qasim, Neamah Hayder Ahmed, Zelentsov Andrei, Amroune Salah

Diagnostyka

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2020

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Vol. 21, No. 3

103--111

EN

In this work a multilevel CFD analysis have been applied for the design of an engine exhaust system include manifold and muffler with improved characteristics of noise reduction and fluid dynamic response. The approaches developed and applied for the optimization process range from the 1D to fully 3D CFD simulation, exploring hybrid approaches based on the integration of a 1D model and 3D tools. Once the best configuration has been defined, the 1D-3D approach has been adopted to confirm the prediction carried out by means of the simplified approach, studying also the impact of the new configuration on the engine performances.

2

The impact of composition dependent and process-related properties in the laser cutting of metallic glassy tapes

Szabo Attila, Lovas Antal

Production Engineering Archives

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2019

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Vol. 23

41--46

EN

A short survey is reported on the advantageous and disadvantageous properties of soft magnetic glassy tapes to build stator and rotor elements for the increase of motor efficiency. The relative high saturation magnetization and the relative permeability of these alloy groups seem to be promising in this application field. On the other hand, the sample thickness (30 μm) displays limitations in terms of a filling factor. High hardness of tapes hinders the effectivity of mechanical shaping. Laser cutting can be successful as shaping method, presuming that the extension (thickness) of heat affected zone (HAZ) can be successfully reduced below 50μm, avoiding the brittleness evolution.

3

Impact of addition oxy-hydrogen gas (HHO) on vehicle engines performance and emissions

Nabil Tamer, Khairat Dawood Mohamed M.

Journal of Mechanical and Energy Engineering

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2019

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Vol. 3, No 2

177--190

EN

The electrolysis process of water produces oxy-hydrogen (HHO) gas that can be used as an energy source to solve the shortage problem of fossil fuel and reduces the exhaust emissions of greenhouse gases from vehicles engines. In this study, HHO dry cell generator was designed, fabricated and tested experimentally to investigate its performance. The hybrid internal combustion engines using HHO gas is considered one of the most important studied applications. The vehicle engines performance and gas emissions are investigated for two different engines; 150CC with carburetor and 1300CC with Electronic Control Unit (ECU). The results recorded the consumption of the fuel is reduced by 14.8% for 150CC engine and 16.3% for 1300CC engine. HHO gas reduced the emission gases by 33% and 24.5% reduction in CO and 27.4% and 21% reduction in HC for 150CC and 1300CC engines respectively. HHO gas can be efficient used as a secondary fuel for vehicle engines.

4

Investigating the Effects of Variable Valve Timing on Spark Ignition Engine Performance

Bapiri Sepehr, Sorusbay Cem

Advances in Science and Technology. Research Journal

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2019

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Vol. 13, no 2

100--111

EN

In this study, a prototype four-stroke spark ignition engine with four cylinders (two valves per cylinder), with and without turbocharger, as well as variable valve timing system to adjustment of variable valve duration has been investigated. This study covers the effects of intake valve opening (IVO), Intake valve closing (IVC), exhaust valve opening (EVO) and exhaust valve closing (EVC) angles on engine performances and fuel economy. The calculations of engine performance were carried out using the 1-Dimensional simulation with AVL BOOST software. The effects of different valve timing strategies and a combination of them from simulations were analyzed and compared with the reference fixed valve timing cases. It was shown that substantial improvements in fuel consumption and performance can be achieved. The improvements of Indicated Specific Fuel Consumption (ISFC) are remarkable in turbocharged models. Furthermore, we can see the noticeable improvements in torque and power in the naturally aspirated engine.

5

Influence of biodiesel from Egyptian used cooking oil on performance and emissions of small diesel engine

Abdelfattah O. Y., Allam S., Youssef I., Mourad M., El-Tawwab A.

Journal of KONES

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2017

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Vol. 24, No. 1

7--21

EN

Egyptian waste cooking oils have special specifications because it expose to high temperatures during use for long hours. In the present experimental study, the performance and emissions of a four strokes, single cylinder, aircooled diesel engine fuelled with two different biodiesel from Egyptian used cooking oil (palm and sunflower) are evaluated at different speeds. The measured performance parameters include torque, fuel consumption and exhaust gas temperature. Brake power, brake specific fuel consumption and brake thermal efficiency was calculated using the measured test data The emission parameters include carbon monoxide, particulate matter and the oxides of nitrogen. The tests have been carried out with different blends of B5 to B100 of biodiesel with diesel fuel. The results showed that the cetane number of sunflower biodiesel has dropped significantly as a result of high temperatures and negatively affected the performance and emissions of the diesel engine also the engine performance with the palm biodiesel blend B5 is closed to diesel fuel also, for B5 CO emission decreased from 53 to 70% while NOx emission decreased from 13 to 80% compared to diesel fuel.

6

Effects of Specific Fuel Consumption and Exhaust Emissions of Four Stroke Diesel Engine with CuO/Water Nanofluid as Coolant

Senthilraja S., Vijayakumar K. C. K., Gangadevi R.

Archive of Mechanical Engineering

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2017

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Vol. LXIV, nr 1

111--121

EN

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.

7

Performance and emissions of a single cylinder diesel engine operating with rapeseed oil and jP-8 fuel blends

Labeckas G., Kanapkienė I.

Combustion Engines

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2015

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R. 54, nr 3

13--18

EN

The article presents experimental test results of a DI single-cylinder, air-cooled diesel engine FL 511 operating with the normal (class 2) diesel fuel (DF), rapeseed oil (RO) and its 10%, 20% and 30% (v/v) blends with aviation-turbine fuel JP-8 (NATO code F-34). The purpose of the research was to analyse the effects of using various rapeseed oil and jet fuel RO90, RO80 and RO70 blends on brake specific fuel consumption, brake thermal efficiency, emissions and smoke of the exhaust. The test results of engine operation with various rapeseed oil and jet fuel blends compared with the respective parameters obtained when operating with neat rapeseed oil and those a straight diesel develops at full (100%) engine load and maximum brake torque speed of 2000 rpm. The research results showed that jet fuel added to rapeseed oil allows to decrease the value of kinematic viscosity making such blends suitable for the diesel engines. Using of rapeseed oil and jet fuel blends proved themselves as an effective measure to maintain fuel-efficient performance of a Didiesel engine. The brake specific fuel consumption decreased by about 6.1% (313.4 g/kW·h) and brake thermal efficiency increase by nearly 1.0% (0.296) compared with the respective values a fully (100%) loaded engine fuelled with pure RO at the same test conditions. The maximum NOx emission was up to 13.7% higher, but the CO emissions and smoke opacity of the exhaust 50.0% and 3.4% lower, respectively, for the engine powered with biofuel blend RO70 compared with those values produced by the combustion of neat rapeseed oil at full (100%) engine load and speed of 2000 rpm.