Yingwen Yan, Yajun Wang, Yuanhao Deng and Jinghua Li
This paper aims to get an in-depth understanding of the fuel spray characteristics to further improve the emission performance of a lean premixed prevaporized (LPP) combustor with…
Abstract
Purpose
This paper aims to get an in-depth understanding of the fuel spray characteristics to further improve the emission performance of a lean premixed prevaporized (LPP) combustor with staged lean combustion.
Design/methodology/approach
In this paper, the fuel spray characteristics in the LPP combustor are experimentally studied by using particle image velocimetry (PIV), and raw data are processed by image-processing technologies for different inlet conditions. The effects of the fuel allocation and pilot atomizer position on fuel spray characteristics are investigated.
Findings
Experiment results show that when only the pilot atomizer is operated, the fuel spray characteristics is worsened by increasing fuel flow rate. The fuel spray fields generated by the pilot atomizer are better at the throat than that at the pilot swirler outlet; when the pilot atomizer and primary injector are operated at the same time with the same inlet fuel air ratio, the spray characteristics are improved by increasing the primary fuel flow rate and decreasing the pilot fuel flow rate. Meanwhile, fuel spray fields generated by the pilot atomizer are better at the throat than that at the pilot swirler outlet.
Practical implications
The present results are useful for further development of the LPP combustor.
Originality/value
An LPP combustor with staged lean combustion technology was proposed; to obtain fuel spray characteristics, image-processing program was compiled; the fuel spray characteristics in the LPP combustor were investigated, especially the effects of the fuel allocation and pilot atomizer position.
Details
Keywords
Meiqiang Wang, Yingwen Chen and Zhixiang Zhou
The purpose of this paper is to examine the industrial production efficiency, pollution treatment efficiency, total factor energy efficiency and water efficiency in China with the…
Abstract
Purpose
The purpose of this paper is to examine the industrial production efficiency, pollution treatment efficiency, total factor energy efficiency and water efficiency in China with the consideration of technological innovation. This study also explores the distribution proportion of technological innovation between industrial production substage and pollution treatment substage.
Design/methodology/approach
A nonparametric method, data envelopment analysis (DEA), is used as the model foundation of this study. Specifically, a novel two-stage range-adjusted measure (RAM-DEA) with shared inputs is constructed to analyze the China’s industrial system. In this study, the panel data of 30 provinces from 2008 to 2015 are used.
Findings
This study found that although the current environmental regulation reduced the efficiency of industrial production, it could significantly improve the pollution treatment level. However, the lack of pollution treatment capacity was still an obstacle for development of China's industrial system. Compared with the total factor energy efficiency, the total factor water efficiency had more room for improvement. The optimal distribution of technological innovation in the two substages performed little change and the distribution roughly followed the “three-seven principle”.
Practical implications
More attention should be paid to improve the pollution treatment level and total factor water efficiency. And more R&D expenditure should be used in the industrial production substage in the eastern coastal areas, while in the inland areas, more R&D expenditure should be used in the pollution treatment substage.
Originality/value
This study proposed a model to environmental efficiency score with considering interval data under two-stage evaluation structure, which could strengthen the theory and expand the application scope of DEA approach.