During the last decade extensive research has been made at Lund University, Sweden, on a lean premix (prevaporize) combustion concept with burnt gas recirculation and a metallic flame holder. From this concept a new lean premixed natural gas combustion chamber with internal combustion gas recirculation (CGR) has been developed for the V160/SOLO 161 Stirling engines. This combustor has ultra-low...

To reveal the inner mechanism of gas explosion dynamic behavior affected by gas equivalent concentration, a high speed Schlieren image system and flow field measurement technology was applied to record the gas explosion flame propagation and flame structure transition. The results show that a flame front structure transition occurs, followed by a flame accelerating propagation process. The lami...

A computational study is performed to investigate the effects of hydrogen addition on the fundamental characteristics of stretched methane/air premixed flame in an opposed flow configuration. The problem is of interest as a potential application to gas turbines and spark-ignition engines, where it has been anticipated that addition of a small amount of hydrogen will extend the lean flammability...

The Olympic flame and torch are significant symbols of the Olympic Games and are important in linking the general public with the festival. They are internationally recognized symbols, particularly important at the Opening and Closing Ceremonies. “It is through the opening and closing ceremonies and the torch relay that the Olympiad must distinguish itself from another series of world champions...

In this experimental study on a laboratory-scale turbulent annular combustor with sixteen swirl-stabilized burners, we the flame-flame and flame-acoustic interactions during different dynamical states associated longitudinal mode of combustor. We simultaneously measure acoustic pressure CH* chemiluminescence emission flame using high-speed camera. Upon increasing equivalence ratio, undergoes fo...

A retrospective analysis was conducted on air samples that were collected in 2005 under the Global Atmospheric Passive Sampling (GAPS) Network around the time period when the Stockholm Convention on Persistent Organic Pollutants came into force. Results are presented for several new flame retardants, including hexabromocyclododecane (HBCD), which was recently listed under the Convention (2013)....

In previous studies, we examined turbulence-flame interactions in carbonburning thermonuclear flames in Type Ia supernovae. In this study, we consider turbulence-flame interactions in the trailing oxygen flames. The two aims of the paper are to examine the response of the inductive oxygen flame to intense levels of turbulence, and to explore the possibility of transition to detonation in the ox...

A computational study has been conducted to determine the critical conditions for the transition from localized flame ignition and propagation to the establishment of a flame ball. Lean H2/air mixtures are investigated using a time-dependent, spherically symmetric code with detailed chemistry, transport, and radiation submodels. Results show that outwardly propagating spherical flames can be ig...

In this paper we study the behavior of a premixed turbulent methane flame in three dimensions using numerical simulation. The simulations are performed using an adaptive time-dependent low Mach number combustion algorithm based on a second-order projection formulation that conserves both species mass and total enthalpy. The species and enthalpy equations are treated using an operator-split appr...

A dominant factor in determining the burning rate of a premixed turbulent flame is the degree to which the flame front is wrinkled by turbulence. Higher turbulent intensities lead to greater wrinkling of the flame front and an increase in the turbulent burning rate. This picture of turbulent flame dynamics must be modified, however, to accommodate the affects of variations in the local propagat...