Fire, Explosions, and Lymphatic Systems: Annual Review of Fluid Mechanics Volume 50

Browse the Annual Review of Fluid Mechanics Volume 50 table of contents.

Before I get to the fire and explosions I want to highlight the lovely article “John Leask Lumley: Whither Turbulence?” by Leibovich and Warhaft that begins this volume.  This biography includes sections about Dr. Lumley’s love and appreciation for vintage cars and good food and wine as well as a look at his contributions to fluid mechanics. It’s a remarkable tribute and a worthwhile read.

Tohidi, Gollner, and Xiao wrote “Fire Whirls” which I found myself thinking about as I watched coverage of the California wildfires:

fl50-fire whirls

Throughout the literature, fire whirls have been identified by a variety of names, including devil, tornado, twister, whirlwind, or even dragon twist (Japanese). Regardless of the name, when the right combination of wind and fire interact, the result is an intensification of combustion with whirling flames that we call the fire whirl. Although the fire whirl or fire tornado shares some features with its atmospheric counterparts, it remains distinct in its source of buoyancy, combusting fuel, structure, and formation patterns. In nature, fire whirls are most often observed in mass fires. These include both large wildland (also known as forest fires or bushfires) and urban conflagrations, such as the burning of cities or towns…

fl50-detonationWhile action movie explosions make it seem easy, a controlled detonation that accomplishes more than looking good on film is difficult and complex to model. “High Explosive Detonation-Conifer Interactions” by Short and Quirk begins by explaining some of the complexity:

The dynamics of a given HE–confiner system depend on the pressure-loading properties of the explosive (magnitude and timescale), while in turn the structure and speed of the detonation reaction zone and the lateral confinement of explosive products are dependent on the material properties of the confining material, such as its density and sound speed. The ability to predict the motion of a detonation in an explosive system (known as the timing) and the response of the confiner to the HE detonation pressure loading depend on our ability to model and understand this detonation–confiner flow coupling…

I found “Lymphatic System Flows” by Moore and Bertram quite interesting especially as it explained the importance of several organs I’d always been curious about:

The lymphatic system as a functional whole includes several organs whose association as a system is not readily apparent. Lymphoid organs include the spleen, thymus, and tonsils; another vital component is the bone marrow where white cells are manufactured…. Functionally, the lymphatic vascular systemfl50-lymph runs in parallel to the blood venous system, in that both return fluids centrally. Lymphatic vessels carry lymph, which is largely water gathered from interstitial tissue spaces. Fluid appears in the interstitial spaces because blood capillary walls are somewhat leaky, allowing part of the aqueous component of blood to escape, along with some proteins…. The lymphatic vascular system scavenges this water and protein, ultimately returning it to the venous circulation via junctions with the subclavian veins at shoulder level. The maintenance of the interstitial milieu is one of its vital functions; if fluid is not returned to the blood system at the same rate as it leaves, the painful and debilitating condition of edema can develop.