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In this paper, we show how vascular design controls the cooling and mechanical performance of a solid square slab heated uniformly and loaded with uniform pressure. The vascular structure is a combination of one grid and several peripheral trees. The designs of trees with grid canopies provide greater robustness than purely dendritic designs. The coolant fluid enters the slab from the center or from the rim, cools the slab to an allowable temperature level, and then exits. Numerical simulations show the flow of the fluid, heat, and stresses. The results indicate that the lowest peak temperature and lowest flow resistance can be achieved with radial channels, and the lowest peak stress can be achieved with trees with canopies. The peak stresses are the lowest when the configuration is a hybrid grid and tree design. There is an optimal ratio of the grid length divided by the slab length for each specified fraction of the fluid volume occupied by the radial channels. When the heating is concentrated in a small area, the peak temperature is smaller when the heated spot is closer to the center of the slab.

A novel rheo-optical device for studying complex fluids in a double shear plate geometry Rev. Sci. Instrum. 84, 013709 (2013); 10.1063/1.4774395Hybrid grid and tree structures for cooling and mechanical strengthHere, we show that a plate heated by a moving beam can be cooled effectively by fluid that flows through a vasculature of channels embedded in the plate. The vascular designs studied are radial, grid and hybrid (radial þ grid). The peak temperature of the plate changes with the path and direction of the moving beam. The strength, size and speed of the beam vary. The peak temperature increases as the beam strength and size increase and as the speed of the beam decreases. The grid and hybrid designs are robust because of loops present in the flow structure. The pressure difference that drives the fluid flow varied. The channel diameter ratios that provide greatest flow access are reported. The cooling performance of the multiscale grid structures is less sensitive to the changes in beam path than the cooling performance of the other structures studied. The effect of adding a vascular structure to the design is dramatic. V C 2012 American Institute of Physics.

Conservation of library collections requires an interdisciplinary approach. Dealing with the agents of deterioration via curative and preventive conservation methods has become a significant goal with new standards and norms in recent years. Preventive conservation aims indirect physical interventions such as climate control, good housekeeping and pest management. The aim of this study is to assess the degradation potential of indoor climate on valuable manuscripts that date back to 12th century, in a historic library in Tire-İzmir, Turkey. Through the study, first the library, namely Necip Paş a Library was continuously monitored by measurements of thermo-hygrometric parameters for one year. Then, the measured data were evaluated for the risk assessment based on the control classes of ASHRAE Chapter 21 to evaluate the mechanical, chemical and biological degradation risks. Finally, the conservation-oriented measures were proposed in order to keep the manuscripts under the better conditions.Results suggest that introducing a heating, ventilation and air-conditioning system to the building should be considered as the last option since natural hygrothermal behavior of the library gives reasonably sufficient evidences to prevent the manuscripts from degradations to some extent. Therefore, passive solutions should be given higher priorities not to disturb environmental past of the historic library.

a b s t r a c tThis paper documents the effect of thermal expansion on a vascularized plate that is heated and loaded mechanically. Vascular cooling channels embedded in a circular plate provide cooling and mechanical strength. The coolant enters the plate from the center and leaves after it cools the plate to an allowable temperature limit. The mechanical strength of the plate decreases because of the embedded cooling channels. However, cooling the plate under an allowable temperature level decreases the thermal stresses. The mechanical strength of the plate which is heated and loaded mechanically at the same time can be increased by inserting cooling channels in it. The mechanical and thermofluid behavior of a vascularized plate was simulated numerically. The cooling channel configurations that provide the smallest peak temperature and von Mises stress are documented. There is one cooling channel configuration that is the best for the given set of boundary conditions and constraints; however, there is no single configuration that is best for all conditions.