Ahmed Amer

This paper represents an experimental study of LPG diffusion flame at elevated preheated air temperatures. The flame is stabilized in a vertical water-cooled combustor by using air swirler. An experimental test rig was designed to investigate the different operating conditions. The burner head is designed so that the LPG fuel issued centrally and surrounded by the swirling air issues from an air swirler. There are three air swirlers having the same dimensions but having different blade angles to give different swirl numbers of 0.5, 0.87 and 1.5. The combustion air was heated electrically before entering the combustor up to a temperature about 500 K. Five air to fuel mass ratios of 15, 20, 30, 40 and 50 were also studied. The effect of preheated air temperature, swirl number and air to fuel mass ratios on the temperature maps, visible flame length, high temperature region (size) and exhaust species concentrations are studied. Some results show that as the preheated air temperature in...

The use of a phase change materials (PCMs) is a very promising technology for thermal energy storage where it can absorb and release a large amount of latent heat during the phase transition process. The issues that have restricted the use of latent heat storage include the thermal stability of the storage materials and the limitation of the container size. The study of the influence of thermal cycling on the properties of PCMs, such as melting temperature and latent heat, is important. It is found that the paraffin wax and fatty acids (e.g., lauric acid, myristic acid, palmitic acid, and stearic acid) have good thermal stability and can be used for solar thermal energy storage applications. However, Calcium chloride hexahydrate (CaCl2. 6H2O) is a good PCM in building applications. 1. Introduction We must not overlook the optimization of current energy usage, even though renewable energy has been developed by researchers to replace traditional fossil-based energy resources. It is important to study how to conserve and improve energy usages such as using thermal energy storage. The different ways of storing energy are mechanical, electrical, thermal, and thermochemical energy storage [1-3]. The basic concept of the thermal energy storage system is to store the thermal energy within the PCM and restore it later when needed. Three kinds of thermal energy storage can be used and these include the sensible heat, latent heat, and thermal chemical storage system. However, the storage density of the latent heat is higher than the sensible heat. Depending on the application, the time of the storage cycle varies from a few hours storage to several months are needed for others[1-3]. This paper presents the influence of thermal cycling tests on the thermophysical properties of phase change materials, namely, melting point temperature and latent heat of fusion.

—This paper represents an experimental study of LPG diffusion flame at elevated preheated air temperatures. The flame is stabilized in a vertical water-cooled combustor by using air swirler. An experimental test rig was designed to investigate the different operating conditions. The burner head is designed so that the LPG fuel issued centrally and surrounded by the swirling air issues from an air swirler. There are three air swirlers having the same dimensions but having different blade angles to give different swirl numbers of 0.5, 0.87 and 1.5. The combustion air was heated electrically before entering the combustor up to a temperature about 500 K. Five air to fuel mass ratios of 15, 20, 30, 40 and 50 were also studied. The effect of preheated air temperature, swirl number and air to fuel mass ratios on the temperature maps, visible flame length, high temperature region (size) and exhaust species concentrations are studied. Some results show that as the preheated air temperature increases, the volume of high temperature region also increased but the flame length decreased. Increasing the preheated air temperature, EINOx, EICO2 and EIO2 increased, while EICO decreased. Increasing the preheated air temperature from 300 to 500 K, for all air swirl numbers used, the highest increase in EINOx, EICO2 and EIO2 are 141, 4 and 65%, respectively.