Experimental Study Of Radiative Properties On Gas-Fired Perforated Ceramic Radiant Burner

In the industrial heating and drying fields, different kinds of electric and gas-fired radiators are widely used, however, the problem exists widely, which is energy uniform heating rate is very low when objects are heated by radiators. Therefore, the study of directionality and uniformity of radiation is important to improve energy uniform heating rate. What's more, it is coincident with the sustainable development strategy of energy saving in our country.In this dissertation, a radiant heater system, which is composed of a directional reflector with a bundle of tubes set in front of flat burner, is regarded as the research object. To improve the properties of the experiment, some alterations have been made in the radiant heater system. We have made a lot of experiments on directionality of radiant energy of cylindrical tube cavity and of square tube cavity and uniformity of cylindrical tubes bundle. To compare the radiant heating properties between gas radiation directional device of cylindrical tube cavity and of square tube cavity, definitions are put forward in this study as follows: directional distribution ratio of radiant energy, apparent hemisphere average emittance and radiation energy collimation rate. Influences of related parameters on the irradiation are as follows: surface temperature of gas-fired radiant burner and heating distance (the distance between the burner end and the object surface) are analyzed in the paper. By comparing the radiant heating properties gas-fired radiation directional device of cylindrical tube cavity with of square tube cavity, we find the different points and than analyze the reasons of the phenomenon. In addition, we also study the irradiance uniformity and the heat flux density distribution on the surface of the heated object of the cylindrical bundle tubes set. Distribution of deviation fraction is used in this study to evaluate the irradiance uniformity of the experiment. Influences of related parameters on the irradiation are analyzed. The parameters include surface temperature of gas-fired radiant burner and heating distance (the distance between the burner end and the object surface).At last, in the condition of the former experiments, we make simulations of the experiments. By comparing the results of simulations with that of experiments, we discover the differences between them, and then analyze the results.