Popis: |
Power cable reflectivities have been measured for both dry and wet conditions using a 10.6 micrometers coherent CO2 laser radar. Measurements were made at a range of 620 m using two types of cable: 1-in.-diameter Grosbeak and 3/8-in. Grouse, at +/- 60 degree(s) aspect angles relative to the normal in increments of 10 degree(s). The cables were both artificially sprayed, in an effort to simulate realistic rainfall rates, as well as being exposed to light rain. Results show that the drop in reflectivity of wet cables compared to dry cables is a function of aspect angle with a mean drop for the Grosbeak and Grouse cables of -5 dB and -1.3 dB, respectively. Measurements of the drying rates of the cables showed a return to the dry state reflectivity in approximately 100 sec after being liberally doused. |