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211 Uppsatser om Voxel engine - Sida 2 av 15
Mean value modelling of a poppet valve EGR-system
Because of new emission and on board diagnostics legislations, heavy truck manufacturers are facing new challenges when it comes to improving the engines and the control software. Accurate and real time executable engine models are essential in this work. One successful way of lowering the NOx emissions is to use Exhaust Gas Recirculation (EGR). The objective of this thesis is to create a mean value model for Scania's next generation EGR system consisting of a poppet valve and a two stage cooler. The model will be used to extend an existing mean value engine model.
ESC-analys och studering av knack på en "Diesel Dual Fuel"-motor
A one-cylinder research engine has been used for studies with a Diesel Dual Fuel concept (DDF). DDF is a concept that utilizes a pilot diesel injection to ignite a homogenous natural gas/air mixture. Emissions and engine efficiency have been analyzed in an emission cycle called European Stationary Cycle (ESC) and the knock/pre-ignition problems with this type of engine have been investigated.At low and mid torque levels, an early diesel injection around 60 crank angles degrees (CAD) before top dead center (TDC) was used. At these loads raw NOxemissions was below EURO 6 level (0.2 g/kWh). NOxwas at EURO 5 level over the complete ESC without after treatment and with SCR at high loads it should be possible to reach EURO 6.One issue with DDF is the high HC emission levels.
Direct-EGR tillämpat på HCCI
The Homogeneous Charge Compression Ignition (HCCI) engine is promising in terms of lowNOx, low particulates and high efficiency. Due to its homogeneous charge, where thecombustion starts almost simultaneously from a number of points in the combustion chamber,only lean mixtures are possible to burn because of the resulting rapid combustion, which is muchfaster than the combustion in an SI-engine or a diesel engine. When richer mixtures are used thecombustion will start earlier and also be more violent.To phase the combustion later and lower the combustion speed, external cooled EGR can beused. The EGR-system used in this thesis uses a divided exhaust channel where one channel andits corresponding valve are used only for transporting EGR back to the intake system.Consequently the EGR-valve is connected to the intake pressure. This system is called Direct-EGR (D-EGR).Engine tests verified that the CA50 indeed is phased later when cooled EGR is used.
Hur enkel- & dubbelportsturbin i kombination med två olika avgassamlare påverkar gasväxlingsprestanda på en Scania V8
The exhaust arrangement on a Scania V8 consists of one manifold at each bank connected to a twin entry turbine (8-2-2). A study in GT-Power has shown improved performance and reduced cylinder to cylinder variations using two manifolds at each bank in combination with a single entry turbine (8-4-1). This thesis work analyses the difference in performance shown in simulation and verify it by engine test.The initial work was focused on simulation in GT-Power. Investigating how exhaust manifold volume and pulses effects the turbine efficiency and the mean effective pressure during the gas exchange. To verify GT-Power simulations four engine tests with different exhaust arrangement have been made.The results from GT-Power simulation indicate that a larger exhaust volume improve the turbine efficiency.
Konstruktionstudie av en ångexpander
This thesis applies to a novel steam expander, one part of a steam engine system, a wobble plateengine. The piston in the expander moves axially with the outgoing rotating shaft and is locatedon a plate, why the engine type is called axial engine. When steam is applied to the plungers theplate wobbles creating a rotation on the shaft going thru the wobble plate. The steam expander issupposed to be used in exhaust gas recovery (bottoming cycle) applications and small scaleenergy production. The commissioner is Ranotor Utveckling AB.
Utveckling av ny musiktjänst på Google App Engine
Idag använder många band och artister utan skivkontrakt olika tjänster på Internet för för att publicera sitt material. Dagens populära tjänster saknar antingen en välutvecklad musikspelare eller en webbplats med community.Syftet med det här arbetet är att med hjälp av molntjänsten Google App Engine, programspråket Python och ramverket Django utveckla en mer komplett tjänst.Arbetet resulterade i grunden till en tjänst samt en rad positiva och negativa slutsatser gällande valet av teknik..
Vätedriven förbränningsmotor : Klarläggande av framtida hållbarhet
Today when new and harder demands on CO2 emissions are developed, vehicle manufacturers must work to develop new engine solutions to new kinds of fuels to replace fossil fuels. A fuel that could be applied is hydrogen. When hydrogen is combusted only water vapor occurs. Hydrogen is known to be explosive and flammable. These properties are both good and bad for combustion.
Zilent Ocean : EL-KONVERTERING AV INOMBORDSMOTORER TILL SEGELBÅTAR
Through extensive research it has shown that today?s sail boat owners are very frustrated concerning the limited choice of engine alternatives offered by today?s market. Besides rising fuel-costs, environmental awareness is very important in today?s society. Hence it is vital to find alternative environmental-friendly motors and replace combustion-engines. Zilent Ocean is an extensive project within Development engineering program at Halmstad University.
Sökmotoroptimering : Metoder för att förbättra sin placering i Googles sökresultat
This paper is a literature study on search engine optimization (SEO) considering the leader of the search engine market: Google. There´s an introductory background description of Google and its methods of crawling the Internet and indexing the web pages, along with a brief review of the famous PageRank algorithm. The purpose of this paper is to describe the major important methods for improved rankings on Google´s result lists. These methods could be categorized as on-page methods tied to the website to be optimized or off-page methods that are external to the website such as link development. Furthermore the most common unethical methods are described, known as ?black hat?, which is the secondary purpose of the text.
Regressionsmodellering av dynamiska råemissioner från statiska mätningar
By using steady-state measurements for predicting emissions under a dynamic drive cycle wouldsave a lot of time and money for the exhaust aftertreatment specialists at Volvo cars. The idea forthis thesis has been to investigate if statistical regression models can be used with good accuracy.Questions included are for example if common operating variables such as engine speed, air-fuelratio etc. is sufficient to predict engine-out emissions over the engine operating range with goodaccuracy. Focus was set on the modelling of warm engine, but also the more complex engineheat-up phase was investigated since it is a great contributor to total emissions. While NOxcouldnot be measured because of malfunctioning measurement equipment, only HC, CO andtemperature at inlet of first catalytic converter has been modelled.
Alternativ motorinkapsling
The problems caused by the current engine casing in aluminum for Volvo Buses Corp. are the mainfoundation for this degree project. Lack of maintenance combined with a construction poorlyadjusted for assembly has resulted in the fact that the engine casings rarely get reassembled whenthe service is completed.The degree project has mainly been following ?Olssons. F, Principkonstruktion, Compendium, Lund?and ?Olssons.
Hur sökfraser är utformade
Millions of people are using search engines every day when they are trying to find information on the Internet. The purpose of this report is to find out how people formulate search queries. The result in this report is based on an empirical study which is based on a search log from the Swedish search engine Seek.se.One of the results in this thesis is that nearly all search queries are based on keywords..
Feldiagnos för RM12 baserad på identifierade modeller
The jetengines of today are growing in complexity. Reliability for aircraft engines are of extreme importance, mainly due to safety reasons but also economical ones. This master thesis deals with faultdiagnosis in the turbine section of RM12, the engine used in Saab/BAe's Gripen. Three different faults which can occur in the turbine section was studied. These faults are: clogged fuel nozzle, hole in outlet guide vane and sensor fault.
Konceptstudie av Waste Heat Recovery System på Tunga Fordon
In today?s fast growing and closely connected society, a reliable and energy efficient transportation system is more than ever desirable. Nowadays the significant part of the transportation sector?s energy demand is supplied by fossil fuels.Improving energy efficiency in combustion engines will result in reduction of fuel consumption and CO2 emissions. A modern internal combustion engine has an efficiency of 30-45 %, where the most energy loss occurs as result of heat losses in the exhaust and cooling systems.
Implementation & utvärdering av spelmotor i WebGL
This report describes an analysis of WebGL together with JavaScript with the aim to examine its limitations, strengths and weaknesses. This analysis was performed by building a 2D game engine containing some dynamic elements such as water, smoke, fire, light, and more. Different algorithms have been tested and analyzed to provide a clearer picture of how these work together. The report will go through the most basic functions of the game engine and describe briefly how these work.The result shows that JavaScript with WebGL can be considered to be a potent toolsets, despite the difficulties caused by JavaScript.In summary, similar projects can be recommended as Javascript and WebGL proved both fun and incredibly rewarding to work with..