Long-runout pyroclastic density currents: Analysis and implications

Hydrodynamics Analysis of Density Currents

Density Current is formed when a fluid with heavier density than the surrounding fluid flows down an inclined bed. These types of flows are common in nature and can be produced by; salinity, temperature inhomogeneities, or suspended particles of silt and clay. Driven by the density difference between inflow and clear water in reservoirs, density current plunges clear water and moves towards a d...

Effects of topography on pyroclastic density current runout and formation of

Laboratory experiments of dilute mixtures of warm talc powder in air simulate dilute pyroclastic density currents (PDCs) and show the effects of topography on current runout, buoyancy reversal, and liftoff into buoyant plumes. The densimetric and thermal Richardson, Froude, Stokes, and settling numbers for our experiments match those of natural PDCs. The laboratory currents are fully turbulent,...

Reconciling Pyroclastic Flow and Surge: the Multiphase Physics of Pyroclastic Density Currents

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Experimental study of turbulence, sedimentation, and coignimbrite mass partitioning in dilute pyroclastic density currents

Residential building and occupant vulnerability to pyroclastic density currents in explosive eruptions

A major hazard during the eruption of explosive volcanoes is the formation of pyroclastic density currents (PDCs). Casualties and physical building damage from PDCs are caused by the temperature, pressure, and particle load of the flow. This paper examines the vulnerability of buildings and occupants to the forces imposed by PDCs along with associated infiltration of PDC particle and gas mixtur...