<p>The objective of the work was to develop a basic control system for an advancedexperimental engine from scratch. The engine this work revolves around is a Saabvariable compression engine.A new control system is developed based on the naked engine, stripped of theoriginal control system. Experiments form the basis that the control system isbuilt upon. Controllers for throttles, intake manifold pressure for pressures lessthan ambient pressure and exhaust gas oxygen ratio are developed and validated.They were found to be satisfactory. The lambda controller is tested with severalparameter sets, and the best set is picked to be implemented in the engine. Modelsnecessary for the development and validation of the controllers are developed.These models include models for the volumetric efficiency, the pressure dynamicsof the intake manifold, the fuel injectors and wall wetting.</p>

The objective of the work was to develop a basic control system for an advancedexperimental engine from scratch. The engine this work revolves around is a Saabvariable compression engine.A new control system is developed based on the naked engine, stripped of theoriginal control system. Experiments form the basis that the control system isbuilt upon. Controllers for throttles, intake manifold pressure for pressures lessthan ambient pressure and exhaust gas oxygen ratio are developed and validated.They were found to be satisfactory. The lambda controller is tested with severalparameter sets, and the best set is picked to be implemented in the engine. Modelsnecessary for the development and validation of the controllers are developed.These models include models for the volumetric efficiency, the pressure dynamicsof the intake manifold, the fuel injectors and wall wetting.

This thesis covers the design and prototyping of an electronic throttle control (ETC) system for a small two-stroke engine. The thesis work is being realized in collaboration between a cooperating company and KTH. The throttle control system is veried with a physical combustion engine. The development process of the control systems is being done mostly in-house in the cooperating company. The company has developed electronic control of fuel and ignition system. In addition to the ETC throttle control system this thesis work also develops a control system of the angular velocity of the combustion engine by controlling the intake air to the small two-stroke engine. Today the air supply to the engine is controlled by a valve mechanically connected to the trigger/gas pedal operated by the user. The focus of the thesis is to investigate the advantages and drawbacks of implementing an electronically controlled air supply to a small two-stroke combustion engine. This master thesis discuss the detailed system design requirement of an ETC system for a small two-stroke engine. The result of this master thesis shows that it is possible to have velocity control on a small two-stroke engine, also minor improvements in acceleration of the small combustion engine is shown when using the ETC system. / Detta examensarbete omfattar design och prototypbygge av ett elektroniskt gasreglagesystem (ETC) for en liten tvataktsmotor. Examensarbetet utfors som ett sammarbete mellan ett sammarbetande foretag och KTH. Gasreglagesystemet verieras med en fysisk forbranningsmotor. Utvecklingsprosessen av styrsystemet bedrivs mestadels internt hos det sammarbetande foretaget. Foretaget har utvecklat elektronisk styrning av bransle och tandsystem. Utover det elektroniska gasreglagesystemet har detta examensarbete ocksa behandlat utvecklingen av ett styrsystem av vinkelhastigheten hos forbranningsmotorn genom att styra insugsluften till den lilla tvataktsmotorn. Idag styrs lufttillforseln till forbranningsmotorn av ett spjall som ar mekaniskt ansluten till avtryckaren som manovreras av anvandaren. Fokus for examensarbetet ligger i att undersoka for- och nackdelar med att implementera ett elektroniskt styrt luftspjall till en liten tva-taktsmotor. Examensarbetet behandlar det detaljerade designkravet hos ett ETC system for en liten tvataktsmotor. Resultatet av detta examensarbete visar att det ar mojligt att ha hastighetsstyrning pa en liten tvataktsmotor, aven sma forbattringar i acceleration pavisas nar ETC systemet anvands.

This diploma thesis deals with the analysis of the intake system of a turbocharged Formu-la Student combustion engine. The thesis contains a brief description of the intake system of a passenger vehicle and the intake system of a Formula Student vehicle. Part of the work is the design of an electronic throttle. The type of throttle valve was selected based on a research of individual types used nowadays. Furthermore, simulations of the flow of the air through the intake system are performed and the results are used in the design cal-culations.

This thesis deals with a design concept of the facility for the educational objectives of the boiling crisis. In the first part, the issue of boiling crisis is explained. There are also examples of some experimental facilities in the world. The second part includes design concept of a loop, which is accompanied by designs of individual devices, such as separator, condenser, exchanger, pump, water tank, electric heater. The thesis also states designs of throttle control, temperature control and flow control.

Dagens behov för energieffektivisering ställer höga krav på industrisektorn som anses vara den största energikonsumenten. Holmen AB är verksam inom massa- och pappersindustrin som är en energiintensiv bransch där sådana stora energianvändare som pumpapplikationer spelar en nyckelroll i produktionen. Denna studie genomfördes för att hjälpa företaget att undersöka vilka energi- och kostnadsbesparingar som kan förväntas om det befintliga pumpreglersättet ändras. Syftet med arbetet var att ta fram en metod för uppskattning av pumpenergiförbrukning, som skulle producera ett underlag för en jämförelseanalys av energiförbrukningen vid olika reglersätt. Studien fokuseras mest på centrifugalpumpar, som dominerar i industriell miljö på grund av sin robusta konstruktion, höga effektivitet och relativt låga behov för underhåll. Men det tillvägagångssätt som har använts i studien kan användas för bedömning av olika typer av pumpar och reglersätt eftersom det byggs på de grundläggande fluidmekanikslagarna. Tidigt i arbetet identifierades de viktiga parametrar som mest påverkar energiförbrukning i centrifugalpumpar och som krävs i beräkningar. Olika reglersätt diskuterades utifrån den befintliga litteraturen och forskningen. Uppskattning av energiförbrukning och energikostnader utfördes för två olika reglersätt, strypreglering och frekvensreglering. I arbetets sista skede jämfördes resultaten för de två reglersätten för att avgöra om det finns en potential för energi- och kostnadsbesparingar vid byte från strypreglering till frekvensreglering. Studiens resultat visar att övergång till frekvensreglering kommer att medföra energibesparingar och som följd besparingar i årliga driftkostnader samt LCC-kostnader. Storleken på besparingarna beror på minskning i varvtalet. Frekvensregleringen är mest lönsam då det önskade flödet skiljer sig mycket från det nominella flödet i systemet, men eventuell försämring av motor- och pumpverkningsgrad måste tas i beaktande. En mer utförlig analys av energiförbrukning vid olika flöden och olika typer av medier rekommenderas att utföras med användning av praktiskt uppmätta effektförbrukningsvärden. / Today's need for energy efficiency places high demands on the industrial sector, which is considered to be the largest energy consumer. Holmen AB is a pulp and paper producer. Pulp and paper production is an energy-intensive branch where pump applications consume large amounts of energy while playing a crucial role in the production process. This study was conducted to help the company investigate what energy and cost savings can be expected if the existing pump control method is changed. The purpose of the study was to develop an approach for estimating pump energy consumption, which would produce a basis for comparative analysis of energy consumption for different control methods. The study focuses mainly on centrifugal pumps, which dominate the industrial environment due to their robust construction, high efficiency, and relatively low maintenance needs. However, this study's approach can be used to assess different types of pumps and control modes as it is based on the fundamental fluid mechanics laws. At the beginning of the study, the key parameters that affect energy consumption in centrifugal pumps were identified to be later used in calculations. Pump control methods were discussed based on the existing literature and research. Estimation of energy consumption and costs was performed for two different control methods, throttle control, and frequency control. In the last stage of the study, two control methods were compared based on the energy consumption calculation to determine whether there is a potential for energy and cost savings when switching from throttle control to frequency control. The results show that usage of frequency control would lead to energy savings and, therefore, to savings in annual operating costs and LCC costs. The amount of the savings depends on the reduction in the rotational speed of the motor. The frequency control is most advantageous when there is a significant difference between the desired flow and the nominal flow in the system. But the potential reduction of motor and pump efficiency must be taken into consideration. A more detailed analysis of energy consumption for different flows and different types of pulp is recommended, with practically measured energy consumption values.