Study On Flow Resistance Characteristics Of Fuel Supply Line In Aeroengine

With the development of the aeroengine and continuously increasing of the compressor pressure ratio, the inlet air temperature of the combustor in the thrust-weight ratio 10 reached to 850 K, which lead to kerosene coking in the fuel supply line. One method to prevent kerosene coking is increasing the flow velocity of the fuel in the fuel supply line and reducing the fuel residence time in the fuel supply line. The fuel line between the fuel supply system and combustor is extremely complex, which include sudden expansion pipe, tee pipe and elbow pipe which all have great resistance loss. So it is technical demand to master the resistance loss regular between pump and nozzle to optimize nozzle design. The numerical simulation are performed by software and experimental study of the short tube, shrinkage pipe, sudden expansion pipe, tee pipe and elbow pipe are carried out to study the flow resistance of the fuel supply line in aeroengine. Besides, the variation about resistance coefficient is analyzed by using the cross sectional streamlines and flow pattern in the fuel line.The results of the study show that the fuel temperature has little effect on flow resistance coefficient as the inlet Reynolds number and structure parameters keep unchanged. Except of inlet Reynolds number, length diameter ratio show an exponential relationship with tube resistance coefficient; the local resistance coefficient of shrinkage pipe and sudden expansion pipe have an exponential relationship with the inlet Reynolds number, and quadratic function relation with sudden expansion ratio or sudden contraction ratio.The exponential form is used to describe the effect of Reynolds number and curvature ratio on the local resistance coefficient of bend. The local resistance coefficient of bend decreasesd rastically with the increasing of bending angle, so the relation between local resistance coefficients of bend and bending angle is quadratic function. As for tee pipe, exponential function is used to connect local resistance coefficient with inlet Reynolds number, split ratio, diameter ratio.In all, this paper concludes the some factors which may influent resistance coefficient and obtain the experimental function of resistance coefficient based on experimental data.