... 0.02–0.28The metals used in refrigeration and air- conditioning systems, suchas steel, copper and aluminium, quickly oxidize or tarnish in air, and the emissivity figure will increase to a value ... theconductive and convective heat transfer, and the overall heat transferfactors in use include the radiation component. Within thistemperature range, the emissivity and absorptivity factors ... transfer coefficient betweenforced draught air and a vertical plane surface ([1], Chapter 3,Table 6) gives:h′ = 5.6 + 18.6V8Refrigeration and Air- Conditioning Table 1.3Number Sign ParametersReynolds...