<p>We present an experimental study on steady gravity currents advancing along a heated wall. The study aims to assess how the structure and dynamics of a wall-heated current are modified with respect to the adiabatic-wall case. The current is generated by a mixture of air and carbon dioxide continuously supplied at the channel inlet. To have a complete point-wise characterization of the flow, simultaneous high-frequency measurements of two velocity components, CO<InlineEquation ID="IEq1"> <EquationSource Format="TEX">$_2$</EquationSource> <EquationSource Format="MATHML"><math> <mmultiscripts> <mrow /> <mn>2</mn> <mrow /> </mmultiscripts> </math></EquationSource> </InlineEquation> concentration, and temperature are performed. An experimental protocol is presented to reconstruct the local fluid density and to estimate vertical and horizontal turbulent fluxes of CO<InlineEquation ID="IEq2"> <EquationSource Format="TEX">$_2$</EquationSource> <EquationSource Format="MATHML"><math> <mmultiscripts> <mrow /> <mn>2</mn> <mrow /> </mmultiscripts> </math></EquationSource> </InlineEquation>, temperature, and buoyancy. The reliability of both the flow measurements and of the estimate of convective heat flux exchanged at the wall is assessed through integral balances of CO<InlineEquation ID="IEq3"> <EquationSource Format="TEX">$_2$</EquationSource> <EquationSource Format="MATHML"><math> <mmultiscripts> <mrow /> <mn>2</mn> <mrow /> </mmultiscripts> </math></EquationSource> </InlineEquation> mass, enthalpy, and buoyancy, performed at different distances from the source. In the heated experiments, a convectively unstable boundary layer forms near the wall, capped by a stably stratified region. The influence of this condition on the first- and second-order flow statistics profiles is examined. With respect to the adiabatic case, the floor heating induces a rise in the wall drag, a reduction in the maximum flow velocity, and a thickening of the gravity current region characterized by a nearly constant velocity. In contrast, the vertical height of the mixing zone, characterized by an almost-constant vertical gradient of the streamwise velocity, does not exhibit a clear dependence on heating intensity.</p>

Experimental study on gravity currents flowing on heated walls

期刊论文
出版模式：

开放获取
发表日期：

2026年6月22日

查看全文

Stefano Lanzini,
Massimo Marro,
Mathieu Creyssels,
Alexandre Azouzi,
Pietro Salizzoni

摘要

We present an experimental study on steady gravity currents advancing along a heated wall. The study aims to assess how the structure and dynamics of a wall-heated current are modified with respect to the adiabatic-wall case. The current is generated by a mixture of air and carbon dioxide continuously supplied at the channel inlet. To have a complete point-wise characterization of the flow, simultaneous high-frequency measurements of two velocity components, CO $_2$ $_{2}$ concentration, and temperature are performed. An experimental protocol is presented to reconstruct the local fluid density and to estimate vertical and horizontal turbulent fluxes of CO $_2$ $_{2}$ , temperature, and buoyancy. The reliability of both the flow measurements and of the estimate of convective heat flux exchanged at the wall is assessed through integral balances of CO $_2$ $_{2}$ mass, enthalpy, and buoyancy, performed at different distances from the source. In the heated experiments, a convectively unstable boundary layer forms near the wall, capped by a stably stratified region. The influence of this condition on the first- and second-order flow statistics profiles is examined. With respect to the adiabatic case, the floor heating induces a rise in the wall drag, a reduction in the maximum flow velocity, and a thickening of the gravity current region characterized by a nearly constant velocity. In contrast, the vertical height of the mixing zone, characterized by an almost-constant vertical gradient of the streamwise velocity, does not exhibit a clear dependence on heating intensity.