Heat Sink Calculation And The Analysis Of Thermal Management For Aircraft Fuel System

With the improvement of aircraft performance and its electronic device,the heat sink increases.Meanwhile,aircraft stealth technology leads to the limited use of ram air. So fuel becomes the preferedheat sink media of the fourth generation aircraft. However, it exists many problems if that the fuel asheat sink. Firstly,fuel consumption and temperature variation makes the fuel heat dynamic changes, itneeds optimization design and fine control;Secondly, with the flight Mach number increases,theaircraft aerodynamic heating problem is certain to affect the fuel temperature.Thus,this study willbasis on these issues, the main job content and results are described as follows:(1) Calculated the heat sink of aircraft. For fuel transport tank, considered the influences of flightmach number, fuel tank thermal resistance and the solar radiation on the fuel temperature. The resultsshowed that the higher Mach number,the smaller tank marerial thermal resistance and with solarradiation,the fuel temperature increased more. For fuel supply tank, with the additional heat sink,inlet fuel temperature and the reflux flow increased,the fuel temperature went up.(2) Used RANS numerical methods to study the aerodynamic heating characteristics of F-5and M6wing. Under two free stream Mach number(Ma=1.5and Ma=2.0), studied the temperaturedistribution of the two airfoil surface.Through comparative analysis of the temperature distribution ofthe upper and lower wing surfaces centerline,we got that they were very close.And the surfacetemperature of the two airfoils were also quite close.Namely when Ma=1.5, TW=373K;WhenMa=2.0, TW=453K.(3) Based on Fluent commercial software, the flow and heat transfer process of fuel tank wassimulated by two-dimensional and three-dimensional. The results showed that the larger Machnumber and the slower fuel consumption rate,the higher temperature of the fuel tank;the higher inlettemperature and the less the amount of fuel storage,the fuel temperature changed more.When Ma=2.0, V=0.1m/s,the outlet temperature increased by about20K. Although the initialtemperature was just293K, the outlet temperature also increased by nearly20K when inlettemperature got to323K.(4) Based on Flowmaster simulation platform, built a simulation model of the aircraft fuel system.Analysed the changes of temperature in each node of the fuel system when the aircraft had differentmissions.