Characteristics Analysis of Joint Acoustic Echo and Noise Suppression in Periodic Drillstring Waveguide

Table 1

Dimensions of drillstring and single acoustic isolator.

Structure	Component	Cross-sectional area (m^2)	Length (m)
Drillstring	Drill pipe	3.39×10^−3	9.11
	Tool joint	16.2×10^−3	0.475
Acoustic isolator	Groove	The same as pipe body	𝐿𝑔 (determined by simulation)
	Convex portion	The same as tool joint	𝐿𝑐 (determined by simulation)