Spectral Analysis of Flame Emission for Optimization of Combustion Devices on Marine Vessels

Abstract

Chemiluminescent emission from OH*, CH* and C2* radicals and its dependence on the equivalence ratio is being investigated in the current study. The aim of this project is to use the results for combustion control on marine vessels and safety checks. The study was conducted in collaboration with Kockumation, a leading company in developing control systems for running boilers and steam turbines on marine vessels. Experiments were conducted at laboratory burners as well as an industrial burner, similar to the one that Kockumation uses. A new detection system for flame monitoring was suggested after the evaluation of the current detectors. The use of photodiodes were proven to be more reliable in detecting the chemiluminescent emission across a wide wavelength range (from UV to near IR region). Furthermore, after the analysis of the data, the CH*/OH* intensity ratio was evaluated as a calibration model for the prediction of the equivalence ratio. In addition to this, the partial least square regression (PLS-R) based multivariate calibration model was tested and the two models were compared. The latter model showed better accuracy in predicting Φ values. New experiments are also suggested for the investigation of additional species that are involved in the combustion process and the further optimization of combustion devices on marine vessels.

Popular Abstract

Combustion processes play an important role in the energy efficiency worldwide. From a simple burner to a complete heating system, combustion is present in everyday life. In industry, especially, flame monitoring is crucial for quality control and safety checks.
The spectral analysis of flame emission is widely used for the investigation of the equivalence ratio and its close-loop control. A high equivalence ratio value corresponds to a rich flame, where there is an excess of fuel that cannot be totally consumed during the combustion process. Furthermore, the molecular species involved in the combustion process can often contribute significantly to the understanding of the flame behavior.
Molecular spectroscopy is regularly used for the identification of the molecules that are present in the reaction zone of the flame. Each molecule emits electromagnetic radiation at specific wavelengths, which is called chemiluminescence and is unique for a certain molecule.
Molecules that obtain energy through chemical reactions emit the excess energy with the form of electromagnetic radiation and return to a more stable condition, i.e. ground state. This chemiluminescent emission is divided into different components, depending on their wavelength, by a spectrometer and can be detected with special cameras like the Intensified Charge-Coupled Device camera.
In this thesis, the chemiluminescent emission of the flame was investigated in various burners in order to use the results for combustion control in steam generator systems for marine propulsion. This project was performed in collaboration with Kockumation, a leading company in this niche. Moreover, the performance of the current flame detection system of the company was studied and a new one was suggested. Further investigation could be contacted for the optimization of the existing combustion devices on marine vessels.

• author: Stamatoglou, Panagiota
• supervisor: Mattias Richter
• organization: Department of Physics; Combustion Physics
• course: FYSM60 20141
• year: 2014
• type: H2 - Master's Degree (Two Years)
• subject: Physics and Astronomy
• keywords: Premixed flames, Equivalence ratio, Chemiluminescence, Partial least squared regression, Flame monitoring
• publication/series: Lund Reports on Combustion Physics LRCP-176
• report number: LUTFD2/TFC-176-SE
• ISSN: 1102-8718
• language: English
• id: 4695221
• date added to LUP: 2014-10-09 09:52:00
• date last changed: 2014-10-22 09:59:13