A jet-stirred chamber for turbulent combustion experiments

Abstract

A novel jet-stirred combustion chamber is designed to study turbulent premixed flames. In the new approach, multiple impinging turbulent jets are used to stir the mixture. It is well known that pair of counterflowing turbulent jets produces nearly a constant intensity along the jet axes. In this study, different numbers of impinging jets in various configurations are used to produce isotropic turbulence intensity. FLUENT simulations have been conducted to assess the viability of the proposed chamber. In order to be able to compare different configurations, three different non dimensional indices are introduces. Mean flow index; Homogeneity index, and Isotropicity index. Using these indices one can compare various chambers including conventional Fan-stirred Reactor. Results show that a concentric inlet/outlet chamber with 8 inlets and 8 outlets with inlet velocity of 20 m/s and initial intensity of 15% produces near zero mean flow and 2.5 m/s turbulence intensity which is much more higher than reported values for Fan-stirred chamber.

Feasibility of Siloxane Removal from Biogas Using an Ultraviolet Photodecomposition Technique

“…To solve the reactor model, the ANSYS Fluent computational fluid dynamics (CFD) software is utilized, which has found in recent years extensive application in the modeling of reactive flows. − To analyze for the UV radiation profiles in the reactor, we employ the Discrete Ordinates (DO) component in ANSYS Fluent to solve the RTE. In ANSYS Fluent, the geometry of the problem is divided into certain control volumes (cells) and the CFD software solves the transport/reaction equations (including the radiation transfer equation, eq ) in each control volume.…”

Model assessment of synthetic jets for turbulent combustion experiments

“…The eight synthetic jets are placed at the corners of a cube inscribed inside of the chamber (Fig. 1), a basis of configuration selected from prior studies on synthetic (Hwang and Eaton 2004) and traditional (Davani and Ronney 2017) jets. Further, the 10-mm-wide synthetic jets are "cavityless" (Fig.…”

“…CVCC facility surveys have been summarized elsewhere (Ravi et al 2012). Generally, most turbulent CVCCs employ impellers (Ravi et al 2012;Bradley et al 2019;Mannaa et al 2019;Morones et al 2019) for relatively uniform turbulence generation, although recent reports suggest that traditional jets (i.e., nozzles) may also be used to create highly uniform turbulence (Davani and Ronney 2017;Davani et al 2019). However, each experimental agitation method has unique limitations, such as vortical biases induced by impellers (Bonhomme et al 2014;Bradley et al 2019;Mannaa et al 2019) or the pumping challenges (i.e., high pressure drop) required by the small openings of jet nozzles.…”

WITHDRAWN: Mathematical modeling of homogeneous combustion processes in small spaces

“…ANSYS FLUENT permits multi-dimensional modeling of physical and chemical phenomena in the processes [33,34], and various modes of heat transfer can be modeled. The species involved in the combustion reaction needs to be explicitly speci ed in ANSYS FLUENT.…”