Radiative resistance model

Radiative Resistance Model of Sphere-Flat Contacts. The radiative resistance of a gap formed by two bodies in elastic contact, such as a sphere-flat or cylinder-flat contact, respectively, is complex because it depends on the geometry of the gap—the surface emissivities of the boundaries, which includes the side walls that form the enclosure. 

Kitscha and Yovanovich [46] and Kitscha [47] proposed the following radiative resistance model for a sphere-disk contact with bounding side walls. All surfaces were assumed to be gray with constant emissivity values el5 e2, and e3 for the sphere, disk, and side walls, respectively. The sphere and disk were assumed to be isothermal at temperatures 7) and T2, respectively. The following expression was proposed ... 

The radiative resistance was approximately 10 times the constriction resistance at the lightest load and 30 times at the highest load. The largest difference between the theory and experiments is approximately -4.7 percent, within the probable experimental error. These and other vacuum tests [47] verified the accuracy of the elastoconstriction and the radiation models. 

T. Iwamoto, M. Akita, T. Kozawa, Y. Yamamoto, D. Werst, D.A. Trifunac, and D. Alexander, Radi ation and photochemistry of onium salts acid generators in chemically amplified resists, Proc. SPIE 3999, 204 213 (2000) A. Nakano, K. Okamoto, Y. Yamamoto, T. Kozawa, S. Tagawa, T. Kai, H. Nemoto, and T. Shimokawa, Deprotonation mechanism of poly(4 hydroxystyrene) and its deriva tives, Proc. SPIE 5753, 1034 1039 (2005) T. Kozawa, A. Saeki, and S. Tagawa, Modeling and simulation of chemically amplified electron beam, x ray, and EUV resist processes, J. Vac. Sci. Technol. B 22(6), 3522 3524 (2004) T. Kozawa, A. Saeki, A. Nakano, Y. Yoshida, and S. Tagawa, Relation between spatial resolution and reaction mechanism of chemically amplified resists for electron beam hthography, J. Vac. Sci. Technol. B 21(6), 3149 3152 (2003). 

Farnworth also presented a theoretical model ofthe combined conductive and radiative heat flows through fibrous insulating materials and compared them with experimental values of the thermal resistances of several synthetic fibre battings and of a down and feather mixture (Table 4.9). No evidence of convective heat transfer is found, even in very low-density battings. The differences in resistance per unit thickness among the various materials may be attributed to their different absorption constants. 

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