533
References
Combination of the equations above results in
with
2p
q
∆ = Z
and v u w
u
u
= + . From this follows (14.6).
14.7.2 Variable Geometry
Derive from the velocity triangles in Fig. 14.3 that adjustable inlet guide vanes allow adaptation to a lower flow rate with almost unchanged rotor work. Note that
incidence occurs at the inlet of a vaned diffuser at a reduced flow rate, decreasing
the efficiency. Observe that a radial compressor may be adapted to a lower flow
rate with almost unchanged rotor work by turning diffuser vanes into a more tangential position (through-flow area is reduced). This generates incidence at the
impeller inlet.
References
1. Balje OE (1981) Turbomachines: a guide to design, selection and theory. Wiley, New York.
ISBN 0-471-06036–4
2. Cumpsty NA (1989) Compressor aerodynamics. Longman Scientific and Technical, London.
ISBN 0-582-01364-X
3. Dixon SL, Hall CA (2014) Fluid mechanics and thermodynamics of turbomachinery, 7th edn.
Elsevier, Amsterdam. ISBN 978-0-12-415954-9
4 . Whitfield A, Baines NC (1990) Design of radial turbomachines. Longman Scientific and Technical, London. ISBN 0-582-49501-6
[
]
s
p
u
w( w w )r dr
r wcos d( ru ) d( r w ) ,
r
r Dq
b
−
=
+
References
Combination of the equations above results in
with
2p
q
∆ = Z
and v u w
u
u
= + . From this follows (14.6).
14.7.2 Variable Geometry
Derive from the velocity triangles in Fig. 14.3 that adjustable inlet guide vanes allow adaptation to a lower flow rate with almost unchanged rotor work. Note that
incidence occurs at the inlet of a vaned diffuser at a reduced flow rate, decreasing
the efficiency. Observe that a radial compressor may be adapted to a lower flow
rate with almost unchanged rotor work by turning diffuser vanes into a more tangential position (through-flow area is reduced). This generates incidence at the
impeller inlet.
References
1. Balje OE (1981) Turbomachines: a guide to design, selection and theory. Wiley, New York.
ISBN 0-471-06036–4
2. Cumpsty NA (1989) Compressor aerodynamics. Longman Scientific and Technical, London.
ISBN 0-582-01364-X
3. Dixon SL, Hall CA (2014) Fluid mechanics and thermodynamics of turbomachinery, 7th edn.
Elsevier, Amsterdam. ISBN 978-0-12-415954-9
4 . Whitfield A, Baines NC (1990) Design of radial turbomachines. Longman Scientific and Technical, London. ISBN 0-582-49501-6
[
]
s
p
u
w( w w )r dr
r wcos d( ru ) d( r w ) ,
r
r Dq
b
−
=
+