The free convection heat transfer of Cu-water nanofluids in a parallelogrammic enclosure filled with porous media is numerically analyzed. The bottom and top of the enclosure are insulated while the sidewalls are subject to limited temperature difference. The Darcy flow and the Tiwari and Das' nanofluid models are considered. The governing dimensionless partial differential equations are numeri...

Domestic chicks bilaterally or unilaterally lesioned to the hippocampus were trained to search for food hidden beneath sawdust by ground-scratching in the centre of a large enclosure, the correct position of food being indicated by a local landmark in the absence of any extra-enclosure visual cues. At test, the landmark was removed or displaced at a distance from its original position. Results ...

In this review the developments made within area of needle-shaped Clark-type gas sensors are summarized. Emphasis will be on design and functioning sensors, but examples use in various environments also included. Microscale have been constructed for O2, N2O, NO, H2S CO2. The tip diameters often 10−70 μm, can considerably larger, O2 with tips down to < 2 μm. excellent long term stability conferr...

A method for enclosing matrix polynomials is proposed. This method is applicable when the matrix is diagonalizable and supplies an interval matrix including the matrix polynomial. The computational cost of this method does not depend on the degree of the polynomial. Hence the proposed method is faster than previous approaches when the degree is large. Numerical results show the properties of th...

Bangladesh has extensive floodplain wetlands covering over 4 million ha. These remain an important source of livelihood fish contribute about 60% of national animal protein consumption, and wetland plants are used for fodder, food and construction. Over fishing, short term leasing of use rights, flood control and drainage, and pollution all have negative impacts. In contrast several projects ha...

This paper studied the cooling performance of a hot electronic chip using nanofluids (NF) mixed convection, implementing Buongiorno’s model NF simulation. The were assumed water-Al2O3 nanoparticles (NP) in range 0 to 4% volume concentration. Six different problems combinations three internal blocks, including triangular, square, and circular geometries, two porous media, sand compact metallic p...

Abstract – This paper investigates overvoltages on the SF6 substation enclosure caused by the switching operation of the interrupter. The paper analyzes the amplitude and the overvoltage duration on the substation enclosure. Switching overvoltages take part in the everyday drive of HV substations and constitute an undesired phenomenon that may often, beside transient disturbances, lead to undes...

Natural convective laminar flow is numerically investigated in a two-dimensional and square enclosure at various angles of inclination respect to horizontal. Two adjacent walls of the enclosure are insulated and the other two are kept at different temperatures. The influence of Rayleigh number representing the effects due to the differential heating of the enclosure walls as well as the effect ...

Limit cycles can occur when navigating unmanned ground vehicles (UGVs) using behavior-based algorithms. Limit cycles occur when the robot is navigating towards the goal but enters an enclosure that has its opening in a direction opposite to the goal. The robot then becomes effectively trapped in the enclosure. This paper reports a solution to the limit cycle problem for robot navigation in very...

This paper presents a numerical study of natural convection within a wavy enclosure heated via corner heating. The considered enclosure is a square enclosure with left wavy side wall. The vertical wavy wall of the enclosure and both of the corner heaters are maintained at constant temperature, T c and T h , respectively, with T h > T c while the remaining horizontal, bottom, top and side walls ...