A Review of Flame Impingement Heat Transfer Studies Part 1: Experimental Conditions

ABSTRACT

A comprehensive review of the experimental conditions that have been used in flame impingement studies is given here. It concerns experiments in which heat transfer rates were measured. The objective of this review is to define the experimental conditions that have been used. A companion paper contains part 2 of the review (Baukal and Gebhart, 1995a). The objective of that review is to specify the diagnostic techniques and measurements used in the tests.

The individual studies are categorized first by target geometry for impinging flames. The geometries were flames: 1) normal to a cylindrical surface, 2) normal to a hemispherically-nosed cylinder, 3) normal to a plane surface, and 4) parallel to a plane surface. The studies are then classified by the oxidizer composition. In most of the experiments, air or pure oxygen was the oxidizer. Some tests concerned oxygen-enriched air combustion. The tests are then categorized by the fuel composition. Methane and natural gas have been the most common fuels used. The equivalence ratio, heat release rate, burner type, nozzle diameter, nozzle Reynolds number and the location of the target, with respect to the burner, are given for each set of the experimental conditions. The target dimensions, its material, surface temperature and surface conditions are also indicated for each study. Most studies used brass, copper or steel targets, without surface treatment, at surface temperatures below 400 K.

Areas for future research are then suggested. Specific examples are given for experimental conditions to be explored. The purpose of some of this proposed research is to improve the basic understanding of the physical phenomena. Other types of research will help designers to develop new and improved processes in flame impingment heating applications.

Key Words:

• Flame jet impingement
• experimental conditions
• heat transfer
• target
• stagnation flow