...John D. Bernardin; Issam Mudawar An experimental study was performed to characterize the transition boiling heat transfer rate from a surface to a stream of impinging water droplets and to extrapolate this information to predict the transition boiling heat transfer of a dilute spray. First...

... relationships of surface heat flux with the spray and surface parameters provide further insight into these processes. The results confirm results for static surfaces, that droplet size is a relatively weak parameter, while droplet momentum flux and surface velocity are important. As the surface velocity...

...Rajkumar Subramanian; M. A. Jog The enhancement of heat transfer by an electric field to a spherical droplet translating at intermediate Reynolds number is numerically investigated using a finite volume method. Two heat transfer limits are considered. The first limit is the external problem where...

...Jesse D. Killion; Srinivas Garimella Recent literature suggests that the droplets that form in horizontal-tube, falling-film absorbers play a major role in the absorption process. The performance of such absorbers is critical to the performance of many absorption heat pump systems. The simulation...

...D. Sivakumar, JSPS Research Fellow; H. Nishiyama, Professor, A simple model is formulated for the analysis of the spreading and solidification processes of a molten metal droplet impinging on a solid substrate. At the first stage, the model evaluates the diameter and the radial velocity...

...D. Sivakumar, Research Fellow; H. Nishiyama, Professor The initial conditions of Madejski’s splat-quench solidification model for the impact of molten droplets on a solid substrate surface are modified by eliminating the adjustable parameter “ε” used in the estimation of initial spreading droplet...

...John D. Bernardin; Issam Mudawar This study presents, for impinging droplets and sprays, a model of the Leidenfrost point (LFP); the minimum liquid/solid interface temperature required to support film boiling on a smooth surface. The present model is an extension of a previously developed sessile...

...V. M. Salazar; J. E. Gonza´lez; L. A. Rivera This work presents the use of laser induced fluorescence for instantaneous temperature measurements of 200 μm water droplets in a monodisperse stream while traveling downward in a standard stagnant atmosphere. The droplets are doped with small...

...L. A. Dombrovsky; S. S. Sazhin A model for convective heating of droplets, which takes into account their finite thermal conductivity, is suggested. This model is based on the assumption of the parabolic temperature profile in the droplets. A rigorous numerical solution, without restrictions...

... the time required to cool a hot surface from 240°C to 120°C by an order of magnitude. water sprays quenching (thermal) dissolving cooling boiling drops evaporation Cooling Droplet Enhancement Heat Transfer Impingement Sprays 6 The effect of dissolving 0.06 mol/l of MgSO...

...M. Dietzel; S. Haferl; Y. Ventikos; D. Poulikakos This paper focuses on the effect that surface tension (Marangoni phenomenon) and viscosity dependence on temperature has on the spreading, transient behavior and final post-solidification shape of a molten Sn63Pb solder droplet deposited on a flat...

...Qiang Cui; Sanjeev Chandra; Susan McCahan We conducted experiments on the effect of dissolving three different salts sodium chloride (NaCl), sodium sulfate Na 2 SO 4 and magnesium sulfate MgSO 4 in water droplets boiling on a hot stainless steel surface. Substrate temperatures were varied from 90°C...

...Paolo Ruffino; Marino di Marzo Two temperatures can be detected in a hot gas laden with water droplets. The lower one is the temperature read by a sensor immersed in the flow. This measurement is affected by significant evaporative cooling resulting in readings much below the real gas temperature...

...G. F. Naterer Phase change heat transfer with impinging supercooled droplets on an ice surface is examined. Partial solidification of incoming droplets leads to an unfrozen water layer above the ice. The significance of temperature variations within the water layer is considered. The multiphase...

... transfer impact (mechanical) sprays Boiling Cooling Droplet Heat Transfer Sprays Traditionally water sprays have been used extensively in metallurgical industries for the cooling of high temperature metals at film boiling. Sprays are made of large drops, in the order of 100 μm or larger...

...Orlando E. Ruiz; William Z. Black, Regents Professor A numerical analysis of the evaporation process of small water droplets with diameters of 1 mm or less that are gently deposited on a hot isothermal solid surface has been performed. This study considers the internal fluid motion that occurs...

... phase and effects of evaporation of the droplets. An impinging mist flow is attractive for study because the impact velocity is relatively high and predictable. Water droplets, less than 15 μm diameter and at concentrations below 10 percent, are considered. The heat transfer is assumed...

... transfer effects, as well as material mixing between the droplet and the substrate are found and quantified and the underlying physics is discussed. Good agreement in the main features of the maximum melting depth boundary between the present numerical results and published experiments of other...

... in the previous studies, because of the use of smaller thermocouple which was capable of measuring the temperature in a thin water sheet and water droplets more accurately. The result of the condensation heat transfer coefficient suggested the breakup of the water sheet into droplets. A pure conduction model...

...Qiang Cui; Sanjeev Chandra, Mem. ASME; Susan McCahan We conducted experiments on the effect of dissolving either a gas (carbon dioxide) or a solid salt (sodium carbonate or sodium bicarbonate) in water droplets boiling on a hot stainless steel surface. Substrate temperatures were varied from 100°C...