الفهرس 
CHAPTER (1) INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Flame impingement heating of solids has been used for many years. The use of
direct flame impingement in industrial furnaces significantly enhances the convective heat transfer rates from combustion products to the walls. This ultimately increases productivity, reduces fuel consumption, and lowers pollutant emissions. Some typical
applications include the melting of scrap metal, shaping glass, and heating metal bars. Many researchers have focused on impinging flame jets concentrated on methane flames or natural gas flames, which impinge normally on a flat plate. Owing
to the constraints on the positioning of the burner or the shape of the impingement plate in some applications, the flame jet may be required to impinge on the target surface at an oblique angle rather than normally. So it is suggested that it is important to understand the influence of the oblique angle on the heat transfer from a flame jet impinging on a plate. A test rig is designed and constructed with the required instrumentation to study
the thermal performance of flame jet impingement. Also, a heat flux sensor is
implemented and assembled to measure local heat flux at various locations on the impingement plate. Obtaining heat flux and surface temperature distribution in the radial direction of the target surface, as well as obtaining a correlation between average heat flux and stagnation heat flux ratio. An experimental investigation was carried out to study the thermal performance
of an impinging laminar premixed flame on a flat plate. The study aimed to analyze the impact of varying burner-to-plate distance (H/d=1 to 4), Reynolds number (Re=1100 to 1900), equivalence ratio (∅=0.8 to 1.2), and oblique angle (𝜃=15⁰ to 90⁰) on thermal performance. The results include the measurements of heat flux and its distribution on the flat plate under different geometrical and operational conditions. Additionally, distribution of surface temperature along the plate was also measured. from the present study it is found that designed heat flux sensors are suitable for measurements in chemically reacting mediums and avoiding problems of thermal equilibrium during the reaction of free active radicals such as OH and CH. When the inner flame core barely reaches the plate, the greatest heat flux caused by the impinging flame jet on the plate. Increasing the value of the Reynolds number of the impinging flame jet significantly improves heat flux due to enhanced heat transfer by convection,
which results from increasing the velocity of unburned gases. The flame in a slightly fuel-rich condition has the maximum heat flux of the impinging flame jet on the plate due to the higher flame temperature owing to complete combustion. When the oblique angle decreases, the maximum heat flux due to
impinging flame jets moves further away from the point where impingement occurs,
and the heat flux profile becomes more asymmetric. The correlation for average heat flux was achieved and can be used with data acquisition systems in many systems and applications to get a specified heat flux distribution. qavg q
0 = 59.827 ∗ 10−6∗ (Re)1.3956 ∗ (Hd)
−1.0724∗ (∅)1.0329 ∗ (cosθ) −1.3471.