“…The problem is that since then, there have been a significant number of published Elder problem simulations which dramatically vary in the way the plumes develop and the number of plumes that remain once the system has reached steady state [Oldenburg and Pruess, 1995;Kolditz et al, 1997;Ackerer et al, 1999;Boufadel et al, 1999;Oltean and Bues, 2001;Frolkovic and de Schepper, 2000;Diersch and Kolditz, 2002]. These discrepancies have been attributed to various issues including mesh resolution, variation in numerical schemes and the use of different formulations for the governing equations [Diersch and Kolditz, 2002;Woods et al, 2003;Woods and Carey, 2007;Park and Aral, 2007;Al-Maktoumi et al, 2007]. More pertinently, using a bifurcation analysis based on a finite volume model, Johannsen [2003] demonstrated a consistent existence of three stable and a further eight unstable steady state solutions, significantly questioning the sensibility of using the Elder problem for benchmarking purposes.…”