A Lif and cars study of CO and NO_x formation in two optically accessible household appliances

摘要

This paper presents the results of optical-diagnostic experiments on two fully operational central heating boilers that have been modified for optical access: a prototype condensing boiler with a fully premixed ceramic burner,and a commercially available conventional boiler with partially premixed bar burners.In this study.LIF was sued to measure the in-situ distributions of NO and CO concentration,while the local temperatures were measured by CARS.The detailed measrueemtns in the combustion chambers are compared with those performed on experimental burners in the open air.It is seen that NO formation in the partially premixed burner is essentially indistinguishable from that in bunsen flames,while the processes in the fully premixed burner are identicla to those of a water cooled sinter burner.The origins of CO in these appliances are also discussed.