Abstract: Abstract: In this paper, a series of experiments were performed over twin parallel polyethylene copper wires with inclination angles from 0 to 90° and spacing from 0 to 17 mm, to analyze the flame pattern, flame height, length and fire spread rate during the combustion process. The results show that: (1) The flame form of inclined parallel twin wires at different distances goes through three stages such as the integrated stage, the approached stage and the independent stage; (2) both flame height (except 90° inclination), flame length, and fire spread rate of twin wires all increase with increasing inclination, while increase and then decrease with increasing spacing; (3) the fire spread rate of the twin wires was initially smaller than that of the single, gradually increased with the wire spacing and reached a maximum in the late stage of integration, and then decreased and remained identical to that of the single in the independent stage; (4) the proportional relationship between the fire spread rate and the flame length is established, and the proportional coefficient is 0.078 for fire spread over twin parallel wires, which is slightly smaller than that for the single wire.

Key words: wire fire, parallel twin wires, inclination angle, wire spacing, fire spread rate