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Publikation Parameterization and results of SWE for gravity currents are sensitive to the definition of depth(American Society of Civil Engineers, 12.03.2021) Venuleo, Sara; Pokrajac, Dubravka; Tokyay, Talia; Constantinescu, George; Schleiss, Anton J.; Franca, Mário J.Rigorously derived shallow water equations (SWEs) are applied to results of large eddy simulation (LES) of a continuously fed gravity current in order to assess (1) sensitivity of current depth results to its definition; (2) coefficients in depth-averaged continuity and momentum equation due to the nonuniformity of density and velocity profiles; and (3) sensitivity of entrainment coefficient to definition of current depth. It is shown that using different definitions of the current depth may produce significantly different numerical results. The coefficients due to nonuniformity in the continuity equation are very close to unity, whereas the coefficients in the momentum flux and the pressure term in the momentum equation are different from unity by a margin that is very sensitive to the definition of current depth. The entrainment coefficient is more sensitive to the selected parameterization than to the definition of the current depth.01A - Beitrag in wissenschaftlicher ZeitschriftPublikation Depth-averaged momentum equation for gravity currents with varying density. Coefficient in pressure term(Taylor & Francis, 31.07.2017) Pokrajac, Dubravka; Venuleo, Sara; Franca, Mário J.Gravity currents are often modelled by means of shallow water equations (SWEs). In these models, simplifications such as the consideration of a constant layer-averaged density are common. This note presents the complete and general derivation of a 2D depth-averaged momentum equation for gravity currents with density and velocity varying in the bed-normal direction. Special attention is given to the pressure term which is evaluated for constant, linear and exponential density profile. The shape of the density profile has implications for the momentum balance: the assumption of constant density leads to an overestimation of the driving force due to pressure gradient by a factor of 33% for linear density profile and up to 50% for an exponential profile. It also leads to an overestimation of celerity in numerical models based on traditional SWEs by factor of 22% and around 40% for linear end exponential density profiles respectively.01A - Beitrag in wissenschaftlicher Zeitschrift