Page 390 - Advanced thermodynamics for engineers

16.8 PROBLEMS 379

minor effect on the principles being illustrated). Assume compression ratio ¼ 9.0:1;
a ig ¼ 695 (25 btdc); flame speed factor variable; and residual fraction ¼ 0.050.

{Hint: to achieve the low intake manifold pressures stated, it is necessary to modify basic.data
in the following way.
Block 200 1:100 800:00 1:34 1:013 290:00
becomes 200 1:100 800:00 1:34 p in T in
Block 550 1:100 320:0 becomes 550 p trapped T trapped :
Use p trapped ¼ 1:1p in ; and T trapped ¼ T in þ 40g

P16.16 Why is the Honda VTEC engine operated at l ¼ 1.18 at high load. Use the basic engine data
for P16.15 for your calculations.