In recent years, buffer layer ablation failure occurs frequently in high voltage cables with corrugated aluminum sheathed structure, but there is a lack of effective method to determine the severity of ablation defects in cable buffer layer. In order to explore the evolution law of gas product concentration during buffer layer ablation, and use it to diagnose the severity of ablation defects, a simulated experimental platform for buffer layer ablation was established in this paper. The law of ablative characteristic gas concentration of buffer layer with different water contents changing with ablation time was investigated,and the variation law was quantitatively analyzed by using a negative exponential function n=-Aexp(-t/τ)+n0. The results show that the concentration of C2H4, C2H6, and H2 increases in a negative exponential relationship with the increase of ablation time. With the increase of water content, the concentration of C2H4 and C2H6 decreases slightly, while that of H2 increases. The generation rate coefficient(A/τ) of C2H4 and C2H6 can reflect that whether the buffer layer is damp, and the A/τ of H2 increases gradually with the increase of water content in buffer layer, which is expected to be one of the bases for judging the degree of damp of buffer layer.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |