Pressure loss prediction model of newtonian fluid hydraulic fracturing in coalbed methane well

In order to predict accurately the pressure loss within coil tube during newtonian fluid coiled tubing fracturing and according to the newtonian fluid rheological characteristics of fracturing fluid used in coalbed methane wells in China, a pressure loss prediction model of slurry based on newtonian fluid in coiled tubing is established. The effect of operation discharge rate, proppant concentration, diameter of coiled tubing and set down ratio on pressure loss in tubing is analyzed. Some suggestions are put forward:(1) friction pressure loss is a major part in pressure loss along the tubing which can be decreased by optimization of tubing diameter and discharge rate; (2) to decrease friction pressure loss, the length of coiled tubing should be reasonably selected according to the set down ratio; (3) large diameter of coiled tubing, large discharge rate and medium proppant concentration should be selected as much as possible under preconditions of meeting the operating pressure of coiled tubing and ensuring proppant carrying ability of water.