The use of compressed air was suggested to increase the reliability and motor lifetime of a gas turbine engine. Experiments were carried out and the results are shown in the form of the variation in circumferential force as a function of the entry angle of the working jet onto the turbine blade. The described start-up method is recommended for use with massive rotors

Dayneko, V. I.

Slobodyanyuk, L. K.

English

NASA Technical Reports Server

General Disclaimer 
One or more of the Following Statements may affect this Document 
 
 This document has been reproduced from the best copy furnished by the 
organizational source. It is being released in the interest of making available as 
much information as possible. 
 
 This document may contain data, which exceeds the sheet parameters. It was 
furnished in this condition by the organizational source and is the best copy 
available. 
 
 This document may contain tone-on-tone or color graphs, charts and/or pictures, 
which have been reproduced in black and white. 
 
 This document is paginated as submitted by the original source. 
 
 Portions of this document are not fully legible due to the historical nature of some 
of the material. However, it is the best reproduction available from the original 
submission. 
 
 
 
 
 
 
 
Produced by the NASA Center for Aerospace Information (CASI) 
https://ntrs.nasa.gov/search.jsp?R=19840008495 2020-03-20T23:32:11+00:00Z
NASA TECHNICAL MEMORANDUM 	 NASA TM-77021
THE START-UP OF A GAS TURBINE ENGINE USING
COMPRESSED AIR TANGENTIALLY FED ONTO THE BLADES OF
THE BASIC TURBINE
L. K. Slobodyanyuk and V. I. Dayneko
(NASA=TH-77021) THE START-UP OF A GAS 	 N84-16563
TUBINE ENGINE USING COMPRESSED AIR
TANGENTIALLY FED ONTO THE BLADES OF THE
BASIC TURBINE (National Aeronautics and	 Unclas
Space Administration) 8 p HC 102/11F k01	 G5/37 11412
Translation of "Zapusk GTD szhatym vozdukhom, podvodimym tan-
gentsial'no na lopatki osnovnoy turbiny", Euergetika, Vol. 20,
September 1977, pp. 135-137.
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
WASHINGTON, DC 20546	 FEBRUARY 1983
rr
ORIGINAL PAGE 18
OF POOR QUALITY
STMNAM TITLE PAM
ii
1. R~ I$&L 4-.+•..«M JtssMw. t1w
TM-77021
4. T#N. •/ $"461010	 THE STAR;-UP OF A GAS
Evz::ruary
NASA
"
TURBINE ENGINE USING COMPRESSED AIR 983
TANGENTIALLY FED ONTO THE BLADES OF THt
BASIC
	 RBINE
6. r"Is"O"l ottW84g4w C6h
^. Av*.rtd	 L Pah.w;"9 Otgoos.N.w R.►w Me.
L.K. Slobodyanyuk and V.I. Dayneko	 1^, ^^ Nw
	
^'—"'
11. C«^^ «a.w Nw
SCITRAM	 t!^ t	 .i R.w"..r	 C10.«dBox 5456
TsaaslatUs
1t• reil
;=Memo
O&Utu, Wd Spaca Adatatatsatlft
Waaninatoa, p .C.	 "L034i
	
14 %www"MansC10M
1L Im"Nas swy NUNS
Translation of "Zapusk GTD szhatym vozdukhom, podvodimym tan
gentsial'no na lopatki osnovnoy turbiny", Energetika, Vol. 2
September 1977, pp. 135-137-
(A78-24149)
146 Abp+'
To increase the reliability and motor lifetime of a gas
turbine engine, the authors suggest using compressed air.
The authors carried out experiments, and the results
are shown in the form of the variation in circumferential
force as a function of the entry angle of the working
jet onto the turbine brade. 	 The described start-up method
is recommended for use with massive rotors.
17. X"
 bN10 ( ►wnw or A	 1L aMN~ 860=00
THIS COPYRIGHTED SOVIET WORK IS RE-
PRODUCED AND SOLD BY NTIS UNDER
LICENSE FROM VAAP, THE SOVIET COPY-.
RIGHT AGENCY. NO FURTHER COPYING,
h s PAR	 c6iGN PRO11. S""I r CINM/. 1101 Ab pop"	 a &@*wpr C%96K Ise 1bs P"d	 IvAi10
rt!3&. UmIdesitled
	 Oaela"LtiM
	
8
VAAP .
ORIGINAL PAGE 6S
OF POOR QUALITY
The Start-Up of a Gas Turbine Engine
Using Compressed Air Tangentially Fed Onto the Blades
of the Basic Turbine
L. I. Slobodyanyuk and V. I. Dayneko
Sevastopol' Instrumentation - Making Institute
Sevastopol; t1krainian SSR
The enhanced reliability and increased motor lifetime of 	 /135*
a gas turbine engine place elevated demands on its servicing
systems, including the start-up system.
One of the ways of raising the reliability of the starter
layout under conditions of lengthy operation is the use of a
starting system without starter. Such a system provides for
the feeding of compressed air directly onto the turbine blades
across special starting nozzles, tangentially arranged about
the perimeter of the turbine housing.
Fig. 1 shows a schematic drawing of the mutual arrangement
of the peripheral section of the working blade and the starting
nozzle.
Fig. 1. Diagram of the arrangement of the
starting nozzle and working blade.
Numbers in the margin indicate pagination in the foreign text.
1
ORIGINAL PAGE 19
OF POOR QUALITY
It is known (1] that the sum of the forces acting on the
system can be found from the theorem of change in momentum of
the flow:
P - Guco—G (-I--G:c•2.
where GO ,G1 ,G2 is the mass rate of flow of the working sub-
stance per unit of time; c 0 ,c1 ,c2
 are the velocities of the
working substance in the system at the inlet and outlet.
The circumferential force is:
P„ I GoCuO — G l Cul ° (izc„z.
Let us suppose that the current is laminar, the relative
velocities of the flow at the inlet and outlet from the blades
are identical, and the losses are provided for by a factor,
which is experimentally determined.
The amount of working substance spreading over the blade
toward the inlet G1 and outlet G2 edges will be, respectively:
G, = G" I -{- sill 8 — arctg
	
sin a"
a
cos uu — 
I — sin
	 0 — arctg	 tin a" u ' _
\	 cos uu — ^^
c
In view of the assumptions, the circumferential force is:
P" : IGO (c„ cos au — u) + G, (M. cos F), — u) -{ G: (W Cos	 u);.
After substituting the values for G1 and G2 we obtain:
iUKIGINAi. PAC- C
OF pOflR QUALI'T'Y 	 j
P,, = too (co cos U*
 — a) - {- 2 J cn u — 2 t"01 CUs uo cos 1 -1
+ Cos
	 (cos a, -- cos :) sin l0 -- arct6	 n us a
	 ''
crn «t, —
As shown by research, a change in the angle a 0 within	 /136
limits of 0 to 30 0
 has little effect on the size of the circum-
ferential force Pu , which is a maximum in this range of angles.
In order to determine the loss factor &, an experiment
was set up at the turbine stage with middle rotor diameter
0.6 m, height 0.1 m, pitch 0.03 m, and blade turn angle
0 = 45°; the exit angles at the edges were a 1 = 90 ° and ^2 = 250.
A possibility was provided for changing the angle a 0 in
the equatorial plane (L'-Z) and the angle Y in the meridional
plane (R-Z).
The quantity of working substance and the rate of flow
were changed by varying the parameters of the working substance
and the geometrical dimensions of the nozzles.
In the experiments the pressure was maintained within
limits of 5.88 bar, the angle a 0 varied from 0 to 45°, the
angle y from 25 to 80°. The circumferential force was measured
by a dynamometer. The magnitude of the force from the jet of
working substance was measured wi t h the blades in various posi-
tions with respect to pitch (with a one degree turn), and then
averaged by a graph analytical method.
The results of i.he experiments are shown in Fig. 2 in the
form of the variation in circumferential force as a function
of the entry angle of the working jet onto the turbine blade a0
3
#1
ORIGINAL PAGE M
OF POOR QUALITY
when the angle y is equal to 40 0 . The loss factor ^, accor-
ding to the experimental findings, was 0.6-0.62.
P M
^ t
IV
ro0 !0 IO ^0 40	 M	 60 V
Fig. 2. The circumferential force as a function
of the nozzle angles of position: 1 - as a
function of angle a0 ; 2 - as a function of
angle y; solid line - calculated curve; broken
line - experimental.
The influence of the angle Y is extreme and, as shown by
the experiments, we may consider Y = 40-45° as most rational;
the given values of ^ also correspond to this value.
After computing P 0 , we can determine the torque
Mt = Pur, whe.Ce r is the outer radius of the rotor, and then
we can also determine the power of the starting layout:
N=Mtn;.
For the investigated case, the specific rate of flow of
compressed air when the pressure of the air in front of the
nozzle is Pp = 9.8 bar and the circumferential velocity varies
between 0 and 70 m/s is:
n0,002M : 0.0033
	 k g/N - S.
.
The specific rate of flow of compressed air, adjusted per
unit of power, under the same air parameters in front of the
nozzle and when u = 70 m/s, is:
Gv vi _g"_ w 0.0193	 kg/s •kW.
4
137
When a small-scale turbine is used as a starter motor,
the rate of flow of working substance will be less, but a rigid
mechanical linkage is required with the rotor of the turbo-
compressor being started, the reducer, and the uncoupling clutch.
As shown by investigations, for purposes of economizing
on working substance when starting up the gas turbine engine
of a small-scale turbine, the start must be done quickly, for
despite the increasing rate of flow per second the overall
amount of air for the start-up is diminished [2]. For example,
for an GTM having a rotor moment of inertia J = 50 kgm2 , when
the rate of flow of air per second is G 0 = 0.5 kg/s the start-up
is done in 122 seconds, while the overall rate of flow of air
is equal to 62 kg; when the rate of flow per second is increased
to 5 kg/s, the rotor attains its starting revolutions (u = 70 m/s)
in 10 seconds, and the overall rate of flow of air is reduced to
50 kg.
An analysis of the start-up without starter reveals that
the consumption of air does not depend on the starting time
(for a rotor similar to that in the preceding example, the
necessary air consumption is 88 kg for any given start-up time).
?
	
	 This peculiarity of the described start-up method recom-
mends it for use with massive rotors, requiring a lengthy time
of acceleration for warm-up, and in this case it is fully
competitive with a small-scale turbine.
A non-rigid gas dynamic transmission with start-up rotor
minimizes the possibility of fracture resulting from incorrect
action on the components of the starting system.
Moreover, large rates of flow of compressed air per start
allow us to recommend the described start-up as the main opera-
tion only when a capacious source of compressed air is present
5
6(a powerful multipurpose compressed air system, tapping of air
from the compressor of a neighboring gas turbine engine in
operation, etc.).
When it is necessary to create a back-up starting system
for the GTE from an energy source other than the main, e.g.
an electric source, we may recommend a similar start-up from
cylinders of compressed air or a compressor of sufficient
power.
References
1. Moiseyev, A. A., Sudovyye parovyye turbiny [Ship Steam
Turbines], Morskoy transport, Moscow, 1958.
2. Yellin, 0. N., Vybor parametrov i raschet osevykh
aktinvnykh turbin dlya privoda turboagregatov [The Selection
of the Parameters and the Design of Axial Active Turbines for
the Drive of Turboassemblies], Oborongiz, Moscow, 1962.
t.
Submitted by the Department 	 [July 14, 19761
for Ship Power Plants


The start-up of a gas turbine engine using compressed air tangentially fed onto the blades of the basic turbine

Abstract

Similar works

Full text

Available Versions

NASA Technical Reports Server