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744 Uppsatser om Engine testing - Sida 2 av 50

Maskinrums design och layout : Varför ett maskinrum ser ut som det gör och hur det går till vid planerandet?

This report is founded in lack of knowledge concerning the design and layout procedureduring a new engine room construction.The prime question is how the engine room takes its form from idea to construction and whathappens in between. We want to give the reader a better understanding in how the work isdone and why it is designed the way it is concerning layout, ergonomics and safety. Duringthis report we will enhance the knowledge concerning regulations and rules that are of greatsubstance such as SOLAS, Swedish Sjöfartsverket and IMO.By contacting the parties involved in the process in newly designing a vessel and its engineroom, we will assume their approaches and experiences. We will study the work progressfrom planning to construction of a vessels machinery spaces. We will with the help ofinterviews with interested parties get an idea of the approach and also compare the finishedproduct a bit depending on company size and resources.The investigation resulted in a good basis for how a ship engine room design takes shape andwhich aspects are taken into account, however, we found that the existing rules concerningengine room layout was very vague and was seen as the most recommendations.

Enhetstestning: Kostnad mot kvalitet

Unit testing is a type of testing technique which is becoming quite fashionable to the developers and companies that are in the business of creating and managing software. Alas there are seldom any concrete data to support the positive claims of the authors in unit testing methodology books. These claims are instead based on empirical studies and the experience of the authors. The problem that arises from this situation is that it becomes problematic for managers and also the developers themselves to convince both customers and their own management to use this type of testing as there is no exact return of investment model. This essay examines this problem from two points, the first point is from the literature itself and interviews conducted with a number of developers at a software company located in Umea, Sweden.

Användartester inom webbutveckling : Är användartester nödvändigt vid utveckling av webbplatser?

The aim of this study is to get a deeper understanding about user tests as well as answer the question about if testing for users is necessary at all times. I've done a comparison between what the literature says, and what a company says, about testing. The tests that's been in focus in this study is prototyping and card sorting tests. Prototyping aims to give the developer feedback about the design and check if there are any obvious problems with the design. A card sorting test can be used to get input about how information architecture should be constructed.

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.

Utvärdering av enhetstestning för Palasso

The market-leading wage and PA-.system for the Swedish public sector Palasso is developed in Karlstad. In order to achieve the highest quality of code , the developing team behind Palasso has been conducting extensive testing. Testing is done to ensure that the software does what it should do. However, the testing has been done at a high level. In order to continue to evolve, the group that develops Palasso has started to look at the new development methods that have become popular in the computer industry in recent years.

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.

Beräkning av värmeförluster och energieffektivisering av elbussar

The ?civilized? world is in need of fossil fuel in order to function. Hybricon AB is a company in Umeå that is developing a technology that hopefully can reduce parts of this need. They are currently testing their two electrical busses (with Hybrid backup) in city traffic on the roads of Umeå in cooperation with the county of Umeå.                               The busses are originally diesel-busses, but the diesel motor has been replaced with two electrical hub-motors with a power of 145 kW each that are powered by batteries.The batteries are charged at the end station after each route. In case the batteries should run low on capacity during driving, they can be recharged by the so called genset.

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..

En utvärderingsmodell för testverktyg : Med inriktning på automatiserade högnivåtester

Testing has always been an important task in the scope of software quality. Though it has never been as much appreciated within the management of the organisations as the software development has. However testing is becoming more attractive within organisations because it becomes more evident how much money working systems saves in contrast to defect ones. A tester often use testing tools to simplify the work progress. There are a lot of tools nowadays but not many evaluating models which helps the tester to know which one to recommend.

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.

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