F ¼
Z t 1
t 2
pdt
ð9:68Þ
where
F Pressure impulse (Pa Á s);
p Gas pressure (Pa).
As shown in Fig. 9.59, the influence of different pressure impulses F 1 , F 2 , F 3 , F 4
on starting characteristics is discussed. As can be seen from the graph, in the case of
comparing the pressure impulse, the pressure impulse is large, the starting time is
fast, the pressure impulse is small, and the starting time is long. At this time, the
peak pressure is not the main factor, but an adjustment factor. A delay tube is
installed on the generator to maintain a certain pressure time and accumulate
pressure impulse through the isolated combustion of the delay grain, so as to
achieve the purpose of fast starting.
Fig. 9.57 Characteristic
relationship between peak gas
pressure, motor frequency,
and starting time
Fig. 9.58 Relationship
between pressure impulse and
starting time
9.5 Starting Characteristics of Electronic and Hydraulic Power Unit
157