Abstract
This paper presents numerical studies of turbulent premixed flames for lean hydrogen and stoichiometric LPG mixtures. The
transient flames under investigation propagate past repeated solid baffle plate(s) and a square obstruction with varied area blockage ratios
in a lab-scale combustion chamber. The chamber allows for up to three removable baffle plates to be equipped in addition to a square
obstacle to increase turbulence intensity within the chamber. The hydrogen mixture is studied at an equivalence ratio of 0.7 and the LPG
mixture is investigated at an equivalence ratio of 1.0. An in-house computational fluid dynamics (CFD) model is applied to numerically
evaluate transient flame propagation. The large eddy simulation (LES) technique is applied for turbulence modelling. Reaction rate
calculations are carried out using a dynamic flamelet model for turbulent premixed flames. Four flow configurations with different area
blockage ratios (ABRs) are used to investigate combustion overpressure. Numerical results are compared against published experimental
data to ascertain the ability of the numerical model in reproducing key combustion events for hydrogen and LPG. A conclusion is drawn
that the increase in blockage ratio raises peak combustion overpressure and the maximum rate of pressure rise. Hydrogen combustion,
albeit at a lower equivalence ratio, results in higher maximum overpressures and peak rate of pressure rise when compared with LPG
transient flames under investigation propagate past repeated solid baffle plate(s) and a square obstruction with varied area blockage ratios
in a lab-scale combustion chamber. The chamber allows for up to three removable baffle plates to be equipped in addition to a square
obstacle to increase turbulence intensity within the chamber. The hydrogen mixture is studied at an equivalence ratio of 0.7 and the LPG
mixture is investigated at an equivalence ratio of 1.0. An in-house computational fluid dynamics (CFD) model is applied to numerically
evaluate transient flame propagation. The large eddy simulation (LES) technique is applied for turbulence modelling. Reaction rate
calculations are carried out using a dynamic flamelet model for turbulent premixed flames. Four flow configurations with different area
blockage ratios (ABRs) are used to investigate combustion overpressure. Numerical results are compared against published experimental
data to ascertain the ability of the numerical model in reproducing key combustion events for hydrogen and LPG. A conclusion is drawn
that the increase in blockage ratio raises peak combustion overpressure and the maximum rate of pressure rise. Hydrogen combustion,
albeit at a lower equivalence ratio, results in higher maximum overpressures and peak rate of pressure rise when compared with LPG
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 7th World Congress on Momentum, Heat and Mass Transfer (MHMT'22) |
| Number of pages | 6 |
| DOIs | |
| Publication status | Published - Apr 2022 |
| Externally published | Yes |
| Event | 7th World Congress on Momentum, Heat and Mass Transfer - Virtual, Lisbon, Portugal Duration: 7 Apr 2022 → 9 Apr 2022 https://mhmtcongress.com/ |
Conference
| Conference | 7th World Congress on Momentum, Heat and Mass Transfer |
|---|---|
| Abbreviated title | MHMT 22 |
| Country/Territory | Portugal |
| City | Lisbon |
| Period | 7/04/22 → 9/04/22 |
| Internet address |
Keywords
- Combustion
- hydrogen
- dynamic flame surface density
- Large Eddy Simulation
- area blockage ratio
- LPG