OCR Text |
Show r^-U, Lf -\ Figure 1. THE COMBUSTION CHAMBER SCHEME WITH DIFFUSION MECHANISM OF GAS COMBUSTION ,1/2 combustion chamber Sc =S (4/n) . Here a spacing between axes of the fuel jets can be used as a size S (Figure 1). L{ greatly increases with the decrease of the excess air (a->l) and significantly depends on the relationship between air flow and gas jet velocities m=UJUg in the inlet cross-section (Figure 2). The more m differs from 1 (no matter, greater or less), the shorter flame length is, i.e. Lf becomes smaller (Figure 3). Limiting values of Li attained at large 1,0 0,8 0,6 0,4 0,2 0.0 1 / • 1 IJ 1 ^ J j (m , • :xxxx> ( 2 J • • • < A A :xxxx> • • • m 3 A' A A A 4$. CXXXXJ i A A A k .-'ll :::••• (XXXX! AA k -•:4 5 .++6 cxx 7 10 15 20 25 2x/[S(4/*)1/2] 30 Figure 2. COMPLETENESS OF FUEL COMBUSTION IN A DIFFUSION FLAME VERSUS RELATIVE COORDINATE x M E A S U R E D FROM THE INITIAL POINT OF JET FEEDING: a=3, C/.=25m/s, 7>rg=573K, S=20mm; here S is the spacing between the axes of fuel jets (see Figure 1); 1 - dg= 1.08mm, t7g=340m/s, w=0.0735; 2-1.5,136.5,0.183; 3-1.8,83.3,0.3; 4-2.2,50.0,0.5; 5-5.0,7.6, 3.29; 6-4.0,12.5,2.0; 7-2.8,26.8,0.93 4 |