russ_watters said:
Ok, I see it, and see that you capitalized "Edge" but not "effect" because that's how it is shown in the video subtitles. Near as I can tell, it's typically called "corner effect" and is about what happens whe a fluid flows around a sharp corner (it accelerates):
Is this your understanding if flow around a house, building, mostly low rise?
The reference given in the post 17 shows that flow around buildings, especially high rise downtown areas, can have complicated air movement patterns.
The upwind velocity U profile need not be that as shown in the figure below, especially if other buildings, or obstacles are in the vicinity. The U shown for the free stream is modelled as either an exponential or as a power function. At ground level, the U velocity is zero, producing the swirl under the stagnation zone. The dead zone is evident on the lee side of the building. ( Note the similarity to an idling car and carbon monoxide poisoning, where the noxious gas can enter the passenger compartment even if the exhaust is exiting at the rear ). ( And snowbank overhang extensions ).
Since the streamlines compress over the building ( and sides as well ), a velocity increase does occur.
It would seem the greatest velocity amplification occurs not at the actual edge but is a function of height and distance from the edge, surpassing U
roof_height, and possibly surpassing U
z under particular conditions.
https://www.aivc.org/resource/air-flow-around-buildings
Chapter 14 of Fundamentals 1981 ASHRAE , a copy of which these nice people have provided.
( Can't find my copy of Fundamentals, same year, ( dagnabit )
https://www.aivc.org/resource/air-flow-around-buildings
