least squares method (lsm) is an accurate and rapid method for solving some analytical andnumerical problems. this method can be used to estimate the average reservoir pressure in well testanalysis. in fact, it may be employed to estimate parameters such as permeability (k) and porevolume (vp). regarding this point, buildup, drawdown, late transient test data, modified muskatmethod, interferenc...

Least squares method (LSM) is an accurate and rapid method for solving some analytical and numerical problems. This method can be used to estimate the average reservoir pressure in well test analysis. In fact, it may be employed to estimate parameters such as permeability (k) and pore volume (Vp). Regarding this point, buildup, drawdown, late transient test data, modified Muskat method, interfe...

The Muskat, or Muskat-Leibenzon, problem describes the evolution of the interface between two immiscible fluids in a porous medium or Hele-Shaw cell under applied pressure gradients or fluid injection/extraction. In contrast to the Hele-Shaw problem (the one-phase version of the Muskat problem), there are few nontrivial exact solutions or analytic results for the Muskat problem. For the stable,...

Abstra t. We address the well-posedness of the Muskat problem in a periodi geometry and in a setting whi h allows us to onsider general initial and boundary data, gravity e e ts, as well as surfa e tension e e ts. In the absen e of surfa e tension we prove that the Rayleigh-Taylor ondition identi es a domain of paraboli ity for the Muskat problem. This property is used to establish the well-pos...

Phenolic compound profiles were investigated by HPLC-MS in two consecutive years to assess genotypic variation in berry skins of nine red Vitis vinifera cultivars. The results showed that the types and levels of phenolic compounds greatly varied with cultivar. Common wine grape cultivars such as Syrah, Cabernet Sauvignon, Cabernet Gernischt and Merlot contained more types of anthocyanins, flavo...

The Muskat problem involves filtration of two incompressible fluids throughout a porous medium. In this paper we shall discuss in 3-D the relevance of the RayleighTaylor condition, and the topology of the initial interface, in order to prove its local existence in Sobolev spaces.

In this note, we show that there exist solutions of the Muskat problem that shift stability regimes: they start unstable, then become stable and finally return to the unstable regime. We also exhibit numerical evidence of solutions with medium-sized L(∞) norm of the derivative of the initial condition that develop a turning singularity.