ZMIANA TEMPERATURY W PROCESIE SAMOWYPŁYWU NAGAZOWANYCH WÓD PODZIEMNYCH

Abstract

TEMPERATURE CHANGE IN THE PROCESS OF SPONTANEOUS OUTFLOW OF GAS-BEARING GROUNDWATERS

Abstract. The article provides a short description of a solution for spontaneous outflow of gas-bearing groundwaters from vertical boreholes. A two-phase flow of gas-water mixture in extraction pipes and chokes was adopted for the solution. Also, differences between water and gas velocities were taken into account. The article focuses chiefly on the problem of thermodynamic flow effects. An assumption was made that the flow of such a mixture occurs in an adiabatic process, i.e. there is no heat exchange between the gas-water mixture and the surroundings. It was also assumed that temperature change during spontaneous outflow results from three processes: degassing of water, gas expansion and frictional resistance. Calculations of temperature change were performed by dividing the extraction pipe and the choke into segments. Subsequently, the calculation results were compared with measurement results obtained on real holes where long-term research or extraction had been conducted. They prove that the presented spontaneous outflow model adequately describes thermodynamic processes.