Dissipative solitons

The major photochemistry consisted of solar EUV and photoelectrons comprising 70 percent and 30 percent respectively, of the initial source of CO2(+) and O(+). The energetic O2(+) provided a substantial source of energy to the ambient ions, distributing of the order of 1.6 x 10 to the -7 power W/sq m at an average of 160 km. This input can be compared to that from the ambient electrons of 1.3 x 10 to the -7 power W/sq m with average deposition at 145 km and from the calculated thermal conduction of 1 x 10 to the -9 power W/sq m at 270 km and 1 x 10 to the -8 power at 230 km for assumed dip angles of 2 deg and 12 deg respectively, for a 10nT magnetic field. At altitudes above 250 km upward, vertical fluxes of the order 6 x 10 to the 10th power/sq m/sec for the thermal ions were calculated. The net ionization of O(+) and CO2(+) by charge exchange with incoming solar wind protons varied from 5 x 10 to the 8th power to 5 x 10 to the 12th power /sq m/sec for assumed field strengths of 50nT to 2nT on the dayside of the planet.

An investigation and analysis of the density and thermal balance of the Martian ionosphere

An alternative pathway for the initiation of dewetting in thin metastable films of partially miscible liquid mixtures is described. In this pathway, phase separation is followed by a dewetting process at the interface between the two phases. Dewetting proceeds (from the sample edges inward) as holes form. The initially smooth film breaks up into droplets at rates much faster than those allowed by classical rupture mechanisms. Marangoni flow appears to be responsible for the initiation of the flow of the dewetting front, and coupling between the flow in the two phases leads to accelerated hole formation.

Alternative dewetting pathways of thin liquid films

Marangoni instability and spontaneous non-linear oscillations produced at liquid interfaces by surfactant transfer.

Pattern formation in large-scale Marangoni convection with deformable interface

Recent studies have elucidated the possibility of solitary wave behavior in Marangoni–Benard instability flows. The present paper takes a look at experiments in both heat‐transfer‐ and mass‐transfer‐driven Marangoni systems to discern nonlinear behavior of the type associated with solitary wave interactions. Direct observation of phase shifts incurred by two Marangoni waves having undergone a head‐on collision are reported. Analysis of experiments exhibiting wave reflection at a solid wall and obliquely interacting waves in Marangoni instability flows also show remarkable similarities with nonlinear behavior in Korteweg–de Vries systems.

Evidence for solitary wave behavior in Marangoni–Bénard convection

Interfacial Wave Motions Due to Marangoni Instability.

In Marangoni–Benard convection with mass transfer from gas phase to liquid phase, it is found that solitary waves, excited and sustained by Marangoni stresses, are very stable during interactions with others, keeping their original shapes and celerities after interactions, thus experiencing at most a phase shift. Both positive and negative phase shifts have been observed for different types of oblique interaction. A ‘‘critical’’ angle, at which zero phase shift occurs as a result of the interaction, has been defined to delineate regions of negative and positive phase shifts.

Oblique and head‐on collisions of solitary waves in Marangoni–Bénard convection

In Marangoni–Benard convection with mass transfer from the air to the liquid, an experimental exploration of reflections of solitary waves at walls has been carried out. Mach stems are observed for small enough incident angles. Upon increasing the incident angle the stem disappears thus leading to regular reflections with, however, the angle of reflection being generally larger than the incident angle.

Wall reflections of solitary waves in Marangoni-Bénard convection

Traveling periodic internal wave trains are generated in liquid layers during the absorption process of a miscible surface-active substance out of the vapor phase. In our nonstationary experimental runs, internal waves are excited by surface waves, which had been previously generated by a surface-tension-gradient-driven instability. The internal wave trains adjust their wave number by an Eckhaus instability. Close to the instability threshold narrow and extended pulses are observed. Furthermore, the wave trains can alter their traveling direction, i.e., one wave train traveling in one direction yields to another train, in general of different wave number, traveling in the opposite direction.

H. Linde

Papers

Evidence for solitary wave behavior in Marangoni–Bénard convection

Interfacial Wave Motions Due to Marangoni Instability.

Oblique and head‐on collisions of solitary waves in Marangoni–Bénard convection

Wall reflections of solitary waves in Marangoni-Bénard convection

Internal waves excited by the marangoni effect