The heat sink with vertically rectangular interrupted fins was investigated numerically in a natural convection field, with steady-state heat transfer. A numerical study has been conducted using ANSYS Fluent software (R16.1) in order to develop a 3-D numerical model.  The dimensions of the fins are (305 mm length, 100 mm width, 17 mm height, and 9.5 mm space between fins. The number of fins used on the surface is eight. In this study, the heat input was used as follows: 20, 40, 60, 80, 100, and 120 watts. This study focused on interrupted rectangular fins with a different arrangement and angle of the fins. Results show that the addition of interruption in fins in various arrangements will improve the thermal performance of the heat sink, and through the results, a better interruption rate as an equation can be obtained.

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The present work includes a numerical study that investigated in a thermal performance of the passive system of a vertical two stores solar chimney. A several models of a vertical solar chimneys were designed, by using the solid work 18 software, that then brought to the Ansys Fluent 18.2 software for simulation, under (Al-Kut, Iraq) city climatic conditions on the hot summer day of (5-8-2018). This simulation was comprised of a five testing models of a two stores solar chimney that oriented to the south and equipped with a wooden two stores facility building that having the size of (1 * 1 * 1) m 3 for each store. The testing models includes a vertical and long vertical solar chimney, with two different positions of (lower and upper) inlet holes. The testing was aimed to choosing the perfect model that could giving a suitable thermal performance under a various value of solar intensities and ambient temperatures during a constant interval of the daylight times. The results proved that the long vertical solar chimney was able to providing a best natural ventilation but with visible rising into the indoor temperatures.

This study introduces numerical investigation of natural convection in metal foam heat sinks with two types of fin edges namely fillet and sharp edges. Aluminum metal foam of various pore densities (5, 10, 20 PPI) and sets of porosities ( ) are used in the simulations. The dimensions of the samples were 100 mm length, 100 mm height, 10 mm thickness and the spacing between fins were kept at 8 mm. Then the metal foam strips were installed onto an aluminum base plate (100 * 100 * 3.5 mm3). The investigation has been performed by control volume method . As well as, the energy equations are established on a principle that based on a local thermal non-equilibrium (LTNE) model in which the temperature of the fluid and the solid matrix are solved separately. The heat input was different from 4 to 30 W in numerical runs and the air was used as a working fluid. The results show that the base temperature of the heat sink is lower for the new design of edges. Therefore, the proposed approach of the heat sink has significant potential to be utilized to enhance the thermal performance of heat sinks and thereby to develop more advanced effective cooling devices and techniques. The maximum enhancement of the heat transfer coefficient with fillet profile reached 5.6% greater than fins with sharp edges

In this study, a simulation for two story building associated with a vertical solar chimney was made by using ANSYS 2022/R1. The study conducted under the climatic conditions of Al-kut city/ Iraq on 5/8/2016. The study involved a comparison between the ventilation performance of SC before and after adding Energy Storage. Al-dura, RT-42, and block-shaped paraffin wax were the three types of PCM that were studied in order to find the optimum ES. The numerical results showed that the best Paraffin wax was Al-dura depending on the average Air Change per Hour (ACH), average indoor temperature, and the ventilation period after sunset. Comparing with the 1st model (without ES), After adding Al-dura wax, the ACH increased by 18.3 % and 9.95 % for 1st and 2nd floor, respectively. whereas, the indoor temperature was reduced by 1.17 k and 0.68 k on the 1st and 2nd floor, respectively. As for the ventilation period, it was  lasted for 5 h after sunset.