Master thesis at Husqvarna, Power & Drive Systems

Evaluating the possibilities of an oxidation catalyst for high HC emissions in a lean exhaust stream for a stratified charge 2-stroke chainsaw engine with 1-d engine simulation software.

About us 

Husqvarna Group is a global leading producer of outdoor power products and innovative solutions for forest, park and garden care. Products include chainsaws, trimmers, robotic lawn mowers and ride-on lawn mowers. 

Husqvarna has introduced a sustainability initiative with the aim to decouple our business growth from our carbon footprint. To make Husqvarna’s Forest and Garden products more sustainable it is important to decrease their HC and CO emissions. This will improve the work environment for the user and at the same time facilitate possibilities to use more renewable fuels and thereby reduce the carbon footprint of the products. One way to accomplish this could be to use an oxidation catalyst on the product. Today extremely few handheld forest and garden products are equipped with catalysts. 

Husqvarna engines already have an advanced, stratified, gas exchange process where the exhaust gases are pushed out by pure air before the fresh combustible charge enters the cylinder. This stratified gas exchange process improves the efficiency and emissions significantly. However, the engine out HC emissions are still very high (approx. 6000 ppm) and due to the scavenging concept, these high HC emissions exists in a globally lean fuel air ratio. This creates challenges if a catalytic converter would be used. 

About the project 

In this project a 1-D engine simulation model in GT-Power should be built on an existing engine model and adding a new model of the catalytic after treatment system. After the model is created, the engine and catalyst should be optimized together for performance, emissions, pressure drop and coping with the thermal challenge in the muffler. 

The intention is that a sister project will start simultaneously where a 2-stroke oxidation catalyst will be developed. From the catalyst project information regarding the catalyst design will feed into the model and in the opposite direction information regarding the air fuel ratio, emissions, flow and temperature will feed into the catalyst project to make the experiments in the Chalmers lab more relevant. 

At the end of the thesis, the goal is to have a function model of the system and suggestions on how the engine should be runed and how the catalyst should be designed to find the best tradeoff between performance, emissions and temperature in the muffler. 

Location 

The work will be divided between Husqvarna in Jonsered and Chalmers in Göteborg. 

How to apply    

Please send in your application with CV and cover letter no later than April 2nd.  

Due to GDPR, we do not accept applications by email.   

For questions regarding the thesis project please contact:  Niklas Enander Husqvarna, niklas.enander@husqvarnagroup.com 

Prof. Louise Olsson Chalmers, louise.olsson@chalmers.se 

Read about Husqvarna Group here:   
https://www.husqvarnagroup.com/    

Last date to apply:

02 April 2023