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A direct radiometric technique is employed in measuring the spectral and directional distribution of radiation intensity at the exposed boundary of a packed bed of stainless steel spheres. A discrete ordinates solution to the radiative transfer equation is also used to complement the experimental procedures. Excellent agreement is observed between the theoretical and experimental results.

The feasibility of using the pseudo-gray-body approximation technique in analyzing the thermal radiative properties of metal surfaces is evaluated via infrared radiometry in three detection wavelength bands. Stainless steel, steel, aluminum and brass are used as specimens in the experiment. Results suggest that the pseudo-gray-body approximation scheme allows the derivation of quantitative data which can be used to effectively characterize the radiative properties of metals.

The determination of local and average heat transfer in the arrays of free-surface liquid jets involves the measurement of local heat transfer data with a two-dimensional infrared radiometer. Array configuration and spacing between jets fail to affect the stagnation Nusselt number under the central jet. Different jet configurations, such as in-line and staggered arrays, show similar local heat transfer characteristics under the central jet. An increase in the nozzle-to-plate spacing transforms the confined submerged central jet flow into the free-surface jet flow.

A spectral radiometric technique is effective in finding a quartz radiant heating tube's equivalent wall temperatures. High temperature measurement enhances accuracy by 50-100 kelvin. This technique provides the first 3.5-4.5 micron wavelength measurements for coefficients of quartz absorption at high temperatures.