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Arctic oil spills are particularly detrimental as they cause extensive ice melting in addition to the environmental pollution they create. However, few studies have been undertaken to reveal how oil-ice interactions impact ice melting. A simultaneous measurement method is developed to investigate the heat transfer pathways from oil slicks to ice. Functional luminescent probes are dissolved in a liquid immiscible with water, which imitates spilled oil. Another luminescent probe is added to seeding particles in order to increase their luminescent intensity. Dual-luminescence imaging and particle imaging velocimetry (PIV) are combined into a single simultaneous measurement method. The developed measurement system shows simultaneous temperature and velocity measurements for natural convection of the immiscible liquid. Successful implementation of the two measurement techniques together is a step toward analyzing heat transfer pathways in a spilled oil adjacent to an ice body, which indicates the extent of melting. 

A series of experiments were conducted to investigate the melting of ice adjacent to a water-immiscible liquid layer (n-dodecane) exposed to radiation from above. The experimental setup consisted of a borosilicate container containing an ice wall and a layer of n-dodecane heated from above. In addition to tracking the movement of the melt front, Particle Image Velocimetry (PIV) and Background Oriented Schlieren (BOS) measurements were conducted on the liquid-phase . Two distinct melting regimes were found to dominate the melting process. First was the uniform melting across the contact area with the immiscible liquid layer for low radiation levels (~1 kW/m 2 ). Second was the lateral intrusion regime, where a depression near free surface of the liquid forms in ice and grows laterally for radiation level greater than ~1 kW/m 2 . The ice surface remained flat and smooth in uniform melting regime, whereas in the lateral intrusion regime a series of rivulets were formed that carved valleys on the ice. PIV measurements showed a surface flow toward the ice for all heat flux levels caused by surface-tension forces. Increase of the heat flux levels caused a transition to multi-roll structure in the flow field. This multi-roll structure, which is accompanied by a recirculation zone near the ice, increased heat transfer coefficient near the surface of the liquid causing lateral intrusion regime. BOS measurements indicated presence of density gradients below the free surface of n-dodecane and in regions near ice that are caused by local small-scale temperature gradients. The current experiments were conducted to explore the melting dynamics and to shed light on the processes that influence the ice melting. Implications of such mechanisms in a real-life scenario, i.e. oil spill in ice-infested waters, needs to be explored further by using more liquids and improved accuracy with diagnostic techniques. 

A series of experiments were conducted to investigate the flow field of a top-heated liquid fuel adjacent to an ice block. The experimental setup consisted of a borosilicate container containing an ice wall and a layer of n-heptane heated from above. Particle Image Velocimetry (PIV) and Background Oriented Schlieren (BOS) measurements were conducted on the liquid -phase. PIV measurements showed a surface flow toward the ice caused by surface -tension forces, which is driven by the horizontal temperature gradients on the liquid surface. A recirculation zone was observed under the free surface and near the ice. The combination of the two flow patterns caused lateral intrusion in the ice, instead of a uniform melting across ice surface. BOS measurements indicated presence of density gradients below the free surface of n-heptane and in regions near the ice block. These density gradients were created by local small-scale temperature gradients. The current experiments were conducted to explore the processes that influence the ice melting by immiscible liquid layers. 

Abstract Arctic oil spills are particularly detrimental as they could cause extensive ice melting in addition to the environmental pollution they create. Floating oil slicks amongst ice floes absorb ambient energy and transfer that energy to the ice to aggravate melting in the thaw season. However, few studies have been undertaken to reveal how oil-ice interactions impact ice melting. This research employs a measurement technique to investigate the heat transfer pathways from oil slicks to the ice. Dual-luminescence imaging and particle imaging velocimetry (PIV) in a side cooled cavity is performed for temperature and velocity measurements of Toluene, respectively. Dual-luminescence imaging captured the spatial temperature distribution of the fuel. Consecutive imaging of the seeding particles in PIV provided the spatial velocity field of the fuel in the cavity. The results show that the convective field is directly coupled with the temperature field, i.e., the temperature difference instigates a flow in the liquid. Successful implementation of the two measuring techniques together is a step toward analyzing heat transfer pathways in a liquid fuel adjacent to an ice body, indicating the extent of melting. 

Arctic oil spills are particularly detrimental as they could cause extensive ice melting in addition to the environmental pollution they create. Floating oil slicks amongst ice floes absorb ambient energy and transfer that energy to the ice to aggravate melting in the thaw season. However, few studies have been undertaken to reveal how oil-ice interactions impact ice melting. This research employs a measurement technique to investigate the heat transfer pathways from oil slicks to the ice. Dual-luminescence imaging and particle imaging velocimetry (PIV) in a side cooled cavity is performed for temperature and velocity measurements of Toluene, respectively. Dual-luminescence imaging captured the spatial temperature distribution of the fuel. Consecutive imaging of the seeding particles in PIV provided the spatial velocity field of the fuel in the cavity. The results show that the convective field is directly coupled with the temperature field, i.e., the temperature difference instigates a flow in the liquid. Successful implementation of the two measuring techniques together is a step toward analyzing heat transfer pathways in a liquid fuel adjacent to an ice body, indicating the extent of melting. 

Recent explosions with devastating consequences have re-emphasized the relevance of fire safety and explosion research. From earlier works, the severity of the explosion has been said to depend on various factors such as the ignition location, type of a combustible mixture, enclosure configuration, and equivalence ratio. Explosion venting has been proposed as a safety measure in curbing explosion impact, and the design of safety vent requires a deep understanding of the explosion phenomenon. To address this, the Explosion Venting Analyzer (EVA)—a mathematical model predicting the maximum overpressure and characterizing the explosion in an enclosure—has been recently developed and coded (Process Saf. Environ. Prot. 99 (2016) 167). The present work is devoted to methane explosions because the natural gas—a common fossil fuel used for various domestic, commercial, and industrial purposes—has methane as its major constituent. Specifically, the dynamics of methane-air explosion in vented cylindrical enclosures is scrutinized, computationally and experimentally, such that the accuracy of the EVA predictions is validated by the experiments, with the Cantera package integrated into the EVA to identify the flame speeds. The EVA results for the rear-ignited vented methane-air explosion show good agreement with the experimental results.