Fig. 3 The unstable symmetric free–free mode shape of the flying wing
Fig. 14 Distribution of Von Mises stresses along the wing (Pa): a) case 1, b) case 2, c) case 3, d) case 4, e) case 5, f) case 6, g) case 7, and h) case 8.
New fronts of research using Constructal Theory
“Body-freedom flutter characteristics of flying wing aircraft vary with engine placement. Here, we show why a certain design parameter (engine placement) influences the aeroelastic flight envelope of the aircraft. The approach is based on the constructal law and the principle that a design that avoids stress strangulations provides better access to the flows that inhabit the system. This is in sharp contrast with trial-and-error techniques such as optimization, which means to opt from among different choices, cases, and designs. Under the same flight condition, the flow of stresses through the aircraft wings is investigated for several configurations including those with maximum and minimum flutter speeds. The results reveal that when the stresses flow smoothly in the wings the stability of the aircraft improves. On the other hand, in the cases in which the engine location causes stress strangulation, the flutter speed decreases considerably. The most severe stress strangulation corresponds to the aircraft configuration with minimum flutter speed (i.e., engine placement at 20% span behind the reference line). The smoothest flow of stresses happens in the configuration with maximum flutter speed (i.e., engine placement at 80% span forward of the reference line).”
Link to the paper at AIAAJ
In a recent paper published in the prestigious “Energy”, Bejan presents his view on Thermodynamics and Science itself.
“Science is like a civilized territory that improves, prospers and expands because it makes life better for the people who belong to it. It expands as long as it keeps producing useful things, which attract people. The civilized welcome the newcomers, the nobodies, provided that they obey the laws, the discipline. People join because their lives become better that way.”
“To fight the barbarians who pillage on the perimeter is a necessary and unpleasant effort, a nuisance, not the objective. As the defeated barbarians are assimilated and civilized, the civilized territory expands and, as a result, life, peace, movement and freedom flourish. The civilized territory that does not fight the pillagers is destined to disappear along with the good way of life that it was sustaining.”
“Thermodynamics, like all the useful artifacts (e.g., science) produced by the civilized, is no different.”
https://www.sciencedirect.com/science/article/pii/S0360544218313896?via%3Dihub (open access for one month)
Constructal Law brings social organization under the big tent of physics
Direction of evolution of humans aggregates and technology in the Economics of ScaleIn view of the complexity and diversity of contemporary social organization, why do individuals came to live (to move) together, to organize themselves in the first place ? Constructal law shows that social organization is a natural phenomenon rooted in the physics of economies of scale. It is a reflection of the physics reality (bio and nonbio) that it is easier to move 1 unit of mass in bulk than to move 1 unit individually. This discovery is the connection between physics and social organization, which brings social organization under the big tent of physics.
The new theoretical framework also reveals the physical meaning of innovation: It is a local design change that liberates the flow over the entire territory inhabited by the organized movers.
#constructal #economics #socialorganization #duke #ufpr
Peder Zane, journalist, writer, puts it in few words “Progress is real. It is natural. It is all around us.” in the recent edition of the News&Observer .
Next week at Villanova Constructal Theory: What the future holds – NSF Workshop and Franklin Institute Symposium the community will be addressing hot topics with the major players in Constructal Theory. @constructal @newsobserver @JPederZane
Duke professor and author Adrian Bejan. Duke Photography