Distribution of temperature Tn within the characteristic sections of the flowline. N0…NM are the characteristic points of the pipeline; L0 …LM is the pipeline length from the installation site of the pressure sensor to the characteristic points N0…NM ; t0…tM is the time of passage of scanning pressure waves through the characteristic points N0…NM ; T1…TM is the temperature in the sections between adjacent characteristic points N0…NM ; M is maximum number of characteristic points of the pipeline