الفهرس 
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Abstract
The present work is concerned with the calculation and measurement of the heat transfer in an oil-flame along a segmented, and water-cooled model furnace. This model furnace has a square cross-section of 400 mm x 400 mm, and a length of 2000 mm. The surface of the furnace is divided into 13 segments, each individually is cooled by a water jacket, thus enabling the measurement of the total wall heat flux distribution along the furnace length • Measurements of the gas temperature, soot concentra- tion, species concentration and the total heat transfer to the wall are c’a.rried out. The temperature is measured by means of a water cooled suction pyrometer. The soot concentration is measured by the Bacharach soot tester using a water cooled probe for sampl ing, while the species concentration is measured by using Infrared gas analyser. The total hea t transmi t ted to the wall is measured by the conductivity-plug-type heat flux meter. It is also,measured by measuring the rate of enthalpy rise of the cool ing wa ter • The effect of the operating parameters, such as the air-to-fuel mass ratio and the swirl angle of the
combustion air on the heat transfer is also investigated in the present work.The radiative heat from the gases to the inner surface of the furnace is calculated by applying the so-called ”Zoning-Method”. It is calcula ted in terms of gas tempera ture, emissivity, transmissivity and the view factor. The gas emissivity is calculated as a function of the gas temperature, soot concentration and partial pressure of the emitting gases. The convective heat from th~ gases to the inner surface of the furnace depends on the gas and wall temper- atures and on the convective heat transfer coefficient. The latter is calculated by applying a modified empirical equation for the heat transfer by convection in pipes .The experiments yielded a complete set of profiles, not only to be fed to the computational algorithm, but also for a compreh~nsive study of the flow, mixing, combustion, and heat transfer characteristics in furnaces. The mathematical modelling of the ”Zone Method” for the furnace has been developed by dividing the furnace into rectangular parallelpipeds. The obtained data from the experiments are fed into the computational algorithm using IBM computer to predict both radiative and convective heat flux incident on furnace’s walls the predicted heat flux profiles are compared with the measured profiles, and the results of the comparisons showed good agreement with experimental data • The heat transfer is found to be increased by decreasing the air-to-fuel ratio as a result of the high soot concentration and ’the high temperature. It also, increases by increasing the swirl angle due to the high flame temperature as a result of efficient combustion.