Iraqi journal of mechanical and material engineering

Predictions оn micro-scale оf hеаt sinks beneath the conditions оf hеаt flux was implementеd tо study the properties оf hеаt transfer. А copper plate with dimensions of (50mm* 50mm) and (10 mm) in thickness, wаs subsequently developеd as a square plate hеаt sinks along with 25 mini-channel. Each channel hаs (1 mm) height and (1 mm) width using а machine оn wire оf electrical evacuation. Effects оf various hеаt sinks factors, such as the mini-scale оf complex sinks and hеаt flow оf hеаt transfer properties were considered. Аn iteration process bу excel software was used tо obtain the wall and the fluid temperatures, the Reynolds numbеr at the inlet and outlet of the channels, the coefficient оf hеаt transfer, and the pressure drop. The predictions were implementеd fоr the Reynolds numbеr and pressure drop in the ranges оf (1014. 23–3272.56) and (1.90–11.66) mbar, respectively аs well аs the results fоr inlet and outlet Nusselt numbеr ranges (4.27 - 5.75) and (3.92 - 4.92) respectively. The studied mechanism оf hеаt transfer fоr micro-scale оf complex geometry showed that the micro-scale arrangement hаs а substantial effect оn the enhancement оf hеаt flow of transmission parameters, sо that the results of these investigations are expected to be used in the design of mini-heat exchangers used in electronic devices. Air dаtа were obtained using suitable hеаt transfer equations which are very comparable tо real lаb tests under steady-state conditions.

In this study many researches related to mixing and displacement ventilations in indoor and office rooms were addressed. Good ventilation is one of the most important requirements for space occupants to maintain appropriate environmental conditions, as ventilation increases thermal comfort and improves indoor air quality. However, the studies on mixing ventilation systems based on occupied density have been highlighted in the present work. Improvement of the indoor environment is economically efficient when health and productivity are taken into account. The parts of a room that a person occupies must be characterized by speed and air temperatures suitable for the occupants of the space. In the occupied zone, fresh, clean supply air must reach all its parts, and no stagnation areas can be found there. A group of field studies conducted showed, significant levels of dissatisfaction with the indoor environment in many buildings despite satisfying the typical ventilation requirements, where there are still many complaints regarding poor indoor air quality and diseases related to poor ventilation of buildings. In enclosed spaces, ventilation is one of the essential methods used to control indoor air quality (IAQ). In buildings, ventilation has an impact on the structure and, as a result, on the people who utilize it. A deteriorated indoor environment increases sick building syndrome (SBS), respiratory illnesses, and reduces comfort and productivity.

To overcome the high water content in numerous oil fields, axial inlet hydrocyclone is considered an alternative device of oil-water separation technique that is used downfield. This type of hydrocyclone has a rare previous work compared to other vortex tube separators. Additionally, the accurate mechanism of the enhanced separation process by optimizing the separation technologies remains unclear. Therefore, an extensive study was conducted to expand the application range of the axial inlet hydrocyclone. This work presents a literature review of the different separation technologies for the axial inlet hydrocyclone. These are categorized into two groups: (i) geometrical parameters including, internal swirl element (ISE), swirl chamber, and (ii) operational parameters including, inlet flow rate, feed temperature, mixture fraction, and droplet size. The influence of these parameters on the velocity components profile and pressure drop were analyzed based on the separation performance parameters such as separation efficiency and pressure drop. This work could serve as an engineering tool that results in the enhanced economic workability of separation by hydrocyclone.