A steady-state heat conduction problem of a nonhomogeneous conical body

Numerous studies and textbooks deal with the steady-state thermal conduction of radially nonhomogeneous circular cylinder. In contrast, there are relatively few studies on the thermal conduction problems of conical solid bodies. This study is intended as a modest contribution to the solution of thermal conductance problems of nonhomogeneous conical bodies. A one-dimensional steady-state heat conduction in nonhomogeneous conical body is considered. The thermal conductivity of the hollow conical body in a suitable chosen spherical coordinate system depends on the polar angle but is independent of the radial coordinate and azimuthal angle coordinate. A functionally graded type of material inhomogeneity is considered. All results of the paper are based on Fourier’s theory of heat conduction in solid bodies.

Tuning of conic parameters using Tikhonov regularization and L-Curve simulation

In this article, a method to infer the parameters of a conic given a set of rectangular coordinates that belong to the geometric entity is shown. The methodology consists of solving a Tikhonov regulation problem where the unregulated term introduces the non-linear nature of the conical body and the regulated the restriction associated to the discriminant of the quadratic equation, then the solution is computed minimizing the resulting cost function where the Regularization parameter is tuned using the L-Curve technique. The model was validated with synthetic and real data from digital images, as well as subject to comparison against other state of the art alternatives. The results show that the method is robust against atypical values and the phenomenon of occlusion present in the data.

Kasnosrednjovjekovne staklene svjetiljke iz Zadra

Glass lamps belong to a number of (late) medieval and post-medieval interiors on the eastern Adriatic coast. They were used to light modest country churches, exuberant city cathedrals, and to less extent profane, primarily residential buildings. In addition to an example of a “bell-shaped” lamp (conical body with elongated hollow handle on the bottom), group of lamps from the area of historical core of Zadar consists of biconical lamps with handles for suspension, known as Islamic or Oriental lamps. They have been dated to the period from the end of the 14th to the beginning of the 16th century. Although fragmented, they are well preserved and they definitely represent an important indicator of typological presence of this everyday object in the Dalmatian littoral.

Laminar–turbulent transition reversal on blunt ogive body of revolution at hypersonic speeds

The influence of flow parameters and nose radius on the location of laminar–turbulent transition is investigated. The model is an ogive-conical body of revolution having half angle about 9°. Experiments were conducted in a shock tunnel at Mach number 5. The transition location was diagnosed by the heat transfer rate distribution determined with the aid of luminescent temperature converters. It is shown that transition reversal can occur either (a) in the absence of turbulent wedges or (b) at a constant level of freestream disturbances. Both increasing and decreasing branches of Re∞,t (Re∞,R) dependency were observed at constant nose radius while varying only the unit Reynolds number.