扩散器涵道
13.扩散器涵道进口处的状态与压气机出气口处相同，即19，049磅。因此，假定扩散器：
出口面积 (A)=205平方英寸 压力 (P)=95磅／平方英寸(表值)
速度 (vJ)=368英尺／秒 质量流量(w)=153磅／秒
燃烧室
14.燃烧室进口处的状态与扩散器出口处相同，即21，235磅。
因此，假定燃烧室：
Thrust distribution
涡轮装置
15.涡轮进口处的状态与燃烧室出口处相同，即55，417磅。
因此，假定涡轮：
……
=向前的推力-41，091磅这个负值意味着一个向后作用的力。
向前的总推力2，186磅
Combustion chambers
14. The conditions at the combustion chamber inlet are the same as the conditions at the diffuser outlet, i.e. 21,235 lb. Therefore, given that the combustion
chamber-
OUTLET Area Pressure Velocity Mass flow (A) (P) (vJ) (W) = = = = 580 sq.in. 93 lb. per sq.in. (gauge) 309 ft. per sec. 153 lb. per sec.
The thrust
WVJ
= (A xP) +. 21,235
g 153 x 309
= (580 x 93) +. 21,235
32 = 55,417 - 21,235 向前的总推力34，182磅
= 34,182 !b. of thrust in a forward direction.
Turbine assembly
15. The conditions at the turbine inlet are the same as the conditions at the combustion chamber outlet,
i.e. 55,417 lb.
Therefore given that the turbine--
OUTLET Area Pressure Velocity Mass flow (A) (P) (vJ) (W) = = = = 480 sq.in. 21 lb. per sq.in. (gauge) 888 ft. per sec. 153 lb. per sec.
The thrust
WVJ
= (A xP) +. 55,417
g 153 x 888
= (480 x 21) +. 55,417
32 = 14,326 - 55,417 = -41,091
This negative value means a force acting in a rearward direction.
Exhaust unit and jet pipe
16. The conditions at the inlet to the exhaust unit
are the same as the conditions at the turbine outlet,
i.e. 14,326 lb.
Therefore, given that the jet pipe--OUTLET Area (A) = 651 sq.in.
Pressure (P) = 21 lb. per sq.in.
(gauge) Velocity (vJ) = 643 ft. per sec. Mass flow (W) = 153 lb. per sec.
涡轮装置
排气装置和喷管
16.排气装置进口处的状态与涡轮出口处相同，即14，326磅。因此，假定喷管：……
210
推进喷管
17．推进喷管进口处的状态与喷管出口处相同，即16，745磅。因此，假定推进喷管：……
需要强调指出的是，这些是基率的计算，象空气引气的影响这类因素已忽略不计。
18.根据各项计算。向前的或正的载荷总数是57，836磅，向后的或负载荷的总数是46，678磅。因而总(总的或全部的)推力为11，158磅。
The thrust WVJ
= (A xP) +.14,326
g 153 x 643
= (651 x 21) +.14,326
32 = 16,745 - 14,326 向前的总推力2，419磅
= 2,419 lb. of thrust in a forward direction.
Propelling nozzle
outlet, i.e. 16,745 lb.
Therefore, given that the propelling nozzle--
17. The conditions at the inlet to the propelling 20. Although the momentum change of the gasnozzle are the same as the conditions at the jet pipe stream produces most of the thrust developed by the
OUTLET Area Pressure
Velocity Mass flow
(A)
= 332 sq.in.
(P)
= 6 lb. per sq.in.
(gauge) (vJ) = 1,917 ft. per sec.
(W)
= 153 lb. per sec.
Thrust distribution
The thrust WVJ
= (A xP) +.16,745
g 153 x 1,917
= (332 x 6) +.16,745
32
= 11,158 - 16,745
= 5,587lb. acting in a rearward direction.
向后总推力5，587磅
It is emphasized that these are basic calculations and such factors as the effect of air offtakes have been ignored.
18. Based on the individual calculations, the sum of the forward or positive loads is 57,836 lb. and the sum of the rearward or negative loads is 46,678 lb. Thus, the resultant (gross or total) thrust is 11,158 lb.
Engine
19. It will be of interest to calculate the thrust of the engine by considering the engine as a whole, as the resultant thrust should be equal to the sum of the individual gas loads previously calculated.
推进喷管
WVJ
engine (momentum thrust = ), an additional
g thrust is produced when the engine operates with the propelling nozzle in a 'choked' condition (Part 6). This thrust results from the aerodynamic forces which are created by the gas stream and exert a pressure 动量推力
across the exit area of the propelling nozzle (pressure thrust). Algebraically, this force is expressed as (P-P0) A.
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