The running of gas turbines with low emissions causes high pressure Pulsations to arise in the combustion chamber. These Pulsations are high amplitude sound vibrations. At some frequencies these are harmful to the gas turbine. Hence these Pulsations are monitored to avoid operating conditions where Pulsations are specifically harmful. It is necessary to expose the system of known Pulsations to verify the functionality of the monitoring process.

Volvo Construction Equipment is a world leading company in construction machinery. Tomaintain the best products, development is prioritized. The master thesis regards sound reductionof the hydraulic system on a wheel loader. The background to the master thesis is asimulation made on the hydraulic system, performed autumn 2005. The result of the simulationshows that the energy of the pressure ripple is reduced when the paralleled hydraulicpumps are phase shifted and reduces each others pump Pulsations.

This master thesis was a subtask of a project called EMIR-1. The goal with the thesis was tobuild a system for particulate mass measurements in one of the engine test cells at KTH. Theparticulate mass measurements are planned to be measured with a TEOM.The exhaust gases must first be diluted with air before the sample is sent to the TEOM.Therefore an ejector diluter for this matter also was designed and evaluated in the thesis.Emissions measurements have been done both with and without dilution to determine thedilution ratio. Tests have been done for different speeds and loads.Problems with stability of the dilution ratio have been an issue throughout the process andpressure Pulsations in the exhaust pipe are believed to be the cause. More tests have to be done tomake sure that this is the problem.One idea is to make the inner diameter of the diluter nozzle smaller and see if it changes thedilution ratio stability.

The master thesis ?Mechanical Integration of an IR-detector in a Micro Cooler? has beenperformed at FLIR Systems AB in Danderyd. FLIR Systems is a world leader in the design,manufacture and marketing of thermal imaging camera systems.The thesis project is divided into to two areas, Production Method and Noise.The Production Method concerns the positioning of a detector on the cold finger within the IRcamera.The detector has to be positiond with very high accuracy at the center of the cold finger,so it can be placed in line with the optical axis to avoid movement of the picture during zooming.The positioning of the detector is at present done with the help of specially designed guides on aplate on top of the cold finger. The design workes well but the special machining needed for thisplate is very expensive.The goal concerning the production method was to derive a new more cost effective method forthe assembling and positioning of the detector on the cold finger by replacing the guides on theplate with a reusable equipment or some other alignement operation.Several concept ideas have been generated with the help of concept generation methods in theform of concept classification trees and concept combinational tables. Two of these conceptswere selected to be further refined.