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. By recovering and converting the thermal energy of a combustion engine to mechanical/electric power the efficiency of the combustion engine can be increased. In this work the performance of a truck engine has been investigated with the aim to increase its efficiency by decreasing the heat losses with a Waste Heat Recovery (WHR) system. Intercooler, coolant system, EGR and exhaust systems have been studied for their heat loss potentials. A model of an ideal Rankine process has been implemented in MATLAB with water as the working fluid. Experimental data sets from a Scania DC1306 and a Volvo D11 engines have served as inputs to the developed MATLAB model. The study shows that an efficiency gain of approximately 2 % can be achieved with a WHR-system where EGR cooler serves as a heat source and 2.5 % with the exhaust as heat source. The combination of both systems can provide an efficiency gain between 4-5 %. / I dagens snabbt växande och energikrävande samhälle är behovet av tillförlitliga och energieffektiva transporterstörre än någonsin önskvärt. En stor del av transportsektorn drivs idag av förbränningsmotorer där energibehovet tillgodoses av fossila bränslen. En energieffektivisering av förbränningsmotorer resultera i minskad bränsleförbrukning och CO2-utsläpp. Hos en modern förbränningsmotor kan en verkningsgrad på 30-45 % normalt uppnås. Den största energiförlusten utgörs av värmeförluster i avgas och kylsystem. Genom att omvandla förbränningsmotorns termiska förluster till mekanisk eller elektriskt arbete kan verkningsgraden höjas. I detta arbete undersöks prestandan hos lastbilsmotorn i syfte att höja dess verkningsgrad genom att ta tillvarata värmeförlusterna. Som lösning introduceras ett externt Waste Heat Recovery (WHR) system där Intercooler, kylsystemet, EGR-och avgassystem tillåts agera som potentiella värmekällor. Systemet beskrivas genom modellering av en ideal Rankineprocess vilket implementerats i MATLAB med vatten som arbetsmedium. Experimentella data från en Scania DC1306 och en Volvo D11 motor har nyttjats som indata till den utvecklade MATLAB-modellen. Studien visar att en effektivitetsvinst på cirka 2 % kan uppnås med ett WHR-system där EGR-kylaren tjänar som värmekälla och 2,5 % med avgaserna som värmekälla. Kombinationen av båda systemen kan åstakomma en effektivitetsvinst mellan 4-5 %.

Rally cars are driven on many different types of surfaces. Each type of surface demands a special type of damper setup. In order to achieve optimum performance on the snow covered and icy Swedish roads, the gravel of the Spanish rallies and the smooth tarmac of the German rallies, a large flexibility in the possible damper settings is required. Prodrive, a British motorsport group, has been racing two Mini Countryman as factory team cars for BMW Mini as of Rally D’Italia in Sardinia in May 2011 and has requested that Öhlins Racing AB equips these cars with dampers. Öhlins Racing AB has been developing a damper for rally applications called the TPX. This damper is equipped with an Active Rebound Control system (ARC). The ARC allows for high levels of grip to be achieved together with good chassis control. The TPX damper with its ARC system is quite complex in structure. As there are many parts in the damper which can be altered, optimizing the damper would require a very large number of tests. A physical model of the TPX damper with its ARC system would reduce the time spent in the lab and help speed up the development of the damper. Prodrive would also like to a have a model of the damper that they can use in their model of the entire car which they use to setup the cars for races and to develop the car. The goal of this Master’s Thesis was therefore to create a model based in MatLab Simulink that qualitatively but not necessarily quantitatively replicated the dampers behavioral trends. Components which are very difficult to model, such as shim stacks, needed not be modeled. Their characteristics could be measured in the lab. During this Master’s Thesis project a model for the TPX damper was created using Simulink to model most of the physical parts of the damper. The rest of the model including its inputs and control were taken care of by a GUI. The model functions so simulations can be performed. Plotting the results of the simulations together with data from experimental tests was also made easy by the GUI. The results from comparisons between the simulated damper and the real object indicate that refinements need to be made to the model before it can be put to use as a tool for helping in optimizing the TPX damper’s construction. Hysteresis in the form of friction as well as damper flexibility does not seem to be negligible. The variation of the oil’s compressibility and the dynamic behavior of the check valves also need to be looked into. The graphs from the simulations seem to replicate the real dampers performance trends as intended. The numerical magnitudes of the data produced by the simulation are however not accurate. Overall the model produced during this master’s thesis seems to be a good step forward on the path to producing a useful model. Some suggestions for the next steps in improving the model are provided.

The wheel corner module represents a new technology for controlling the motion of avehicle. It is based on a modular design around the geometric boundaries of a conventionalwheel. The typical WCM consists of a wheel containing an electrical in-wheel propulsion motor, a friction brake, a steering system and a suspension system. Generally, the braking,steering and suspension systems are controlled by means of electrical actuators. The WCMis designed to easily, by means of bolted connections and a power connector, attach toa vehicle platform constructed for the specic purpose. All functions are controlled viaan electrical system, connecting the steering column to the module. A WCM vehicle cancontain two or four wheel corner modules.The purpose of this thesis is to serve as an introduction to wheel corner module technology.The technology itself, as well as advantages and disadvantages related to wheelcorner modules are discussed. An analysis of a variety of wheel corner module concepts iscarried out. In addition, simulations are conducted in order to estimate how an increasedunsprung mass aects the ride comfort and handling performance of a vehicle.Longitudinal translation over two types of road disturbance proles, a curb and a bump,is simulated. A quarter car model as well as a full car model is utilized. The obtainedresults indicate that handling performance is deteriorated in connection to an increase dunsprung mass. The RMS value of the tire force uctuation increases with up to 18%,when 20 kg is added to each of the rear wheels of the full car model. Ride comfort is deteriorated or enhanced in connection to an increased unsprung mass, depending on the disturbance frequency of the road. When subjected to a road disturbance frequency below the eigenfrequency of the unsprung mass, ride comfort deterioration is indicated. The RMS vertical acceleration of the sprung mass increases with up to 6%, in terms of the full car model. When subjected to a road disturbance frequency above the eigenfrequency ofthe unsprung mass, decreased RMS vertical acceleration of up to 25% is noted, indicatinga signicantly enhanced ride comfort. Implementation of wheel corner module technology enables improved handling performance,safety and ride comfort compared to conventional vehicle technology. Further development, e.g. in terms of in-wheel motors and alternative power sources, is however required. In addition, major investments related to manufacturing equipment andtechnology is regarded as a signicant obstacle in terms of serial production.

Marine Jet Power, MJP wishes to investigate the possibility of transforming their current Thrust Prediction Program, TPP written in C++ source code into a more up to date tool for their sales staff. The old TPP, though an accurate and precise tool, is not documented and lacks commentaries in the source code. Therefore the beginning of this master thesis was about documenting and investigates what methods were used to calculate the performance of the water jet system.The next step was splitting the long C++ source code in to smaller functions, this was done using MatLab where several m-files were created with the different functions in. C++ syntax and structure differs from MatLab so the source code must be translated in to MatLab syntax. Once the new TPP was translated and the calculation results were identical with the old TPP a Graphical User Interface, GUI was created and presented to MJP. The current MatLab TPP is not finished, only two of four calculation modes have been translated and MJP wants modifications in the GUI. The additional work needed in order to have the sales tool MJP wishes is currently discussed.

Globalization is reaching the furthest corners of the world and with globalizations comes a rising demand on transportation. In shipping; a significant cost both to the ship owners and the environment are the fossil fuels used for propulsion, even a small reduction in the wave resistance can bring considerable reductions both in operating costs and emissions for such ships. When designing a ship it is important to be able to make fast and accurate predictions of its resistance so that more efficient hull forms can be selected early in the design process. A panel method based on potential flow is a fast scheme to determine the wave resistance and is therefore suitable to be used early on in the design process. Here it is shown that potential flow can be improved by including Rayleigh damping, added viscous effects that will make the flow dissipative. Dissipative Green functions are employed in the proposed technique with the resulting velocity potential determined from a combination of a source distribution and a modified distribution of vortices on submerged 2D bodies. NACA hydrofoils, Joukowski hydrofoils and cylinders are used to test the model. The pressure distribution is more in line with experimental results than previous numerical methods without added viscosity for the NACA hydrofoils. The surface profile has very good comparison with existing numerical results for a NACA hydrofoil in subcritical speeds. However the results are very poor for the Joukowski hydrofoil. There is therefore reason to develop this method further in both 2D and 3D.

Detta examensarbete är en konceptuell fartygsprojektering av en ny serie fartyg åt Sjöräddningssällskapet. Rapporten presenterar ett förslag till en ny sjöräddningsbåt som kan ersätta två äldre fartygstyper, i storleksordningen tio meter, och det behov som täcks av dem. Fartygets huvuduppgifter fastställs vara bogsering och sjuktransport och det opererar mestadels i skyddade vatten under sommarhalvåret. Examensarbetet är handlett av Thore Hagman, Sjöräddningssällskapet och examinator Karl Garme, KTH,Marina System. Mycket arbete har lagts på att skapa ett kostnadseffektivt förslag vilket gav att en befintlig skrovform anpassades för att passa den kravställning som togs fram tillsammans med Sjöräddningssällskapets ledning och räddningsbesättningar. Huvuddata: Loa 9,95 m Boa 4,2 m T 0,65 m Deplacement 5,65 ton fullastat Motorer 2x350 hk utombordare Fart 42 knop Bunker 1,5 m2 bensin Räckvidd +280 Nm i 35 knop Fartyget har ett fristående däckshus som, om det dimensioneras och byggs vattentätt, gör fartyget självrätande. Däckshuset rymmer fyra besättningsmedlemmar och tre passagerare alternativt en patient på bår. Båten har utrustning för brandbekämpning, länspumpning, bogsering, sjuktransport, ”On-scenecoordination”-kommunikation och räddning av nödställda i vattnet.

Rubber is a highly complicated material. Its properties are strongly dependent of temperature, preload, frequency, amplitude and filling materials. In order to have better knowledge about how rubber reacts for these different parameters, a number of different papers that treats these parameters have been reviewed. Main focus is on dynamic properties of carbon-black filled rubber. Mechanical models of rubber isolator with different kinds of possible solution have been suggested. A basic mathematical equation is derived to estimate the static and dynamic stiffness of a rubber isolator depending on the preload for a geometry that is commonly used by Atlas Copco Rock Drills AB. Tests of a rubber isolator with the same geometry is also conducted to validate the model. It is shown that the model corresponds very well to measurement data.

To enhance the drivability and increase safety a major part of Scania’svehicles is fitted with a retarder. The retarder is a complementary brake system that assists the vehicles mechanical brakes. When running a retarder some oil leakage can occur. The main source to the leakage is oil sump ventilation but there is also some contribution from the solenoid valve block that controls the retarder. Test results from the test rig shows that with rather simple methods the oil leakage in form of oil mist can be captured. The efficiency of for instance concept 1 with half the volume and a chicane interior was as high as 99 to 100 %. For the concept 2 with the expanded metal filter the efficiency was in the order of 96 to 100 %. From testing it has also become clear that there is a problem to feed the oil back into the oil sump. Initial tests shows that the retarder is rather sensitive regarding the placing of the feedback channel. It is considered that the best option is to only use the feedback channel that enters the internal drain of the retarder. Measurements show that the airflow in the tube from the accumulator could reach velocities up to 67 m/s. It is considered that the best solution is to have two separate chambers, one for the accumulator and one for the oil sump ventilation, the safety valve and the proportion valve. The reason for this is that the combination of oil in a chamber together with high airflow from the accumulator is disastrous and the retarder leaks far worse compared to original. The conclusion is therefore that it is important to separate air from the accumulator from places where oil can occur. Tests also revealed that the size of an external volume is not of any great importance when it comes to colleting oil. There was no significant difference in between of using a volume of 0.64 l or 0.19 l. However regarding overfilling it is favorable to have a larger volume since this increases the retarder’s capability to withstand oil leakage when it is overfilled.

In a world of fierce competition that is the reality for heavy truck manufacturers, it is important to optimize every step of production to the greatest extent. The Swedish truck manufacturer SCANIA early adopted such ideas and has put great efforts to implement a concept called lean production. As a part of the company’s strive for continuous improvement, all parts of the value adding chain shall be as efficient as possible.  Previously this work has been focused inside the SCANIA organization but as demands on production volume and profit margin increases, focus turns outside the factory premises. A bodywork is fitted as a last step in the completion of many trucks. This is done by external companies called bodybuilders, outside the control of the factory. In this thesis, the bodybuilder induced waste is addressed from a global perspective. The report is entirely based on interviews with people inside SCANIA, SCANIA’s Swedish business unit, bodybuilders in both Sweden and Poland and a Swedish employer’s organization. Through these interviews, the difficulties surrounding the subject have been mapped from different perspectives. As a complement to the interviews, a program that calculates the annual waste related to shortened chassis frames has been developed. The main waste inducing problem areas found in this thesis is: -        Poor communication between seller and bodybuilder before specifying and ordering the chassis. -        Poor communication between factory and bodybuilder regarding existing chassis preparations. -        A high degree of customer involvement in the bodybuilder process on the Swedish market. -        High price sensitivity on the Polish market makes chassis specified without preparations more attractive. -        Highly diverse customer demands on the Swedish market. -        Insufficient ordering tools to meet the customer demands of individually customized vehicles. -        Discrepancies between the global focus at factory and the local nature of the market on which the sellers exist. The costs related to shortened chassis frames alone is estimated to cost SCANIA 5 000 000 SEK annually in terms of reduced chassis frame waste and decreased costs for bound investments when chassis are standing at bodybuilders. In order to go from today’s annual production of 70 000 vehicles to the long-term goal of 150 000 vehicles/year, it will be crucial to reduce waste throughout the whole production chain. This will require better prepared vehicles from factory, better ordering software for the sellers and less rigid customer behaviour on certain markets. The increased communication between seller, bodybuilder and factory will be necessary and could be implemented through cooperation between selected bodybuilders and sellers in a preferred program.

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