Tur"bine (?), n. [L. turbo, -
inis, that which spins or whirls round, whirl.] A water wheel,
commonly horizontal, variously constructed, but usually having a series of
curved floats or buckets, against which the water acts by its impulse or
reaction in flowing either outward from a central chamber, inward from an
external casing, or from above downward, etc.; -- also called turbine
wheel.
&fist; In some turbines, the water is supplied to the wheel from below,
instead of above. Turbines in which the water flows in a direction parallel
to the axis are called parallel-flow turbines.
Tur"bine (?), n. A form of steam
engine analogous in construction and action to the water turbine.
There are practically only two distinct kinds, and they are typified
in the de Laval and the Parsons and Curtis turbines. The de
Laval turbine is an impulse turbine, in which steam impinges
upon revolving blades from a flared nozzle. The flare of the nozzle
causes expansion of the steam, and hence changes its pressure energy
into kinetic energy. An enormous velocity (30,000 revolutions per
minute in the 5 H. P. size) is requisite for high efficiency, and the
machine has therefore to be geared down to be of practical use. Some
recent development of this type include turbines formed of several de
Laval elements compounded as in the ordinary expansion engine. The
Parsons turbine is an impulse-and-reaction turbine,
usually of the axial type. The steam is constrained to pass
successively through alternate rows of fixed and moving blades, being
expanded down to a condenser pressure of about 1 lb. per square inch
absolute. The Curtis turbine is somewhat simpler
than the Parsons, and consists of elements each of which has at least
two rows of moving blades and one row of stationary. The bucket
velocity is lowered by fractional velocity reduction. Both the Parsons
and Curtis turbines are suitable for driving dynamos and steamships
directly. In efficiency, lightness, and bulk for a given power, they
compare favorably with reciprocating engines.
Tur"bine (?), n. [L. turbo, -
inis, that which spins or whirls round, whirl.] A water wheel,
commonly horizontal, variously constructed, but usually having a series of
curved floats or buckets, against which the water acts by its impulse or
reaction in flowing either outward from a central chamber, inward from an
external casing, or from above downward, etc.; -- also called turbine
wheel.
&fist; In some turbines, the water is supplied to the wheel from below,
instead of above. Turbines in which the water flows in a direction parallel
to the axis are called parallel-flow turbines.
Tur"bine (?), n. A form of steam
engine analogous in construction and action to the water turbine.
There are practically only two distinct kinds, and they are typified
in the de Laval and the Parsons and Curtis turbines. The de
Laval turbine is an impulse turbine, in which steam impinges
upon revolving blades from a flared nozzle. The flare of the nozzle
causes expansion of the steam, and hence changes its pressure energy
into kinetic energy. An enormous velocity (30,000 revolutions per
minute in the 5 H. P. size) is requisite for high efficiency, and the
machine has therefore to be geared down to be of practical use. Some
recent development of this type include turbines formed of several de
Laval elements compounded as in the ordinary expansion engine. The
Parsons turbine is an impulse-and-reaction turbine,
usually of the axial type. The steam is constrained to pass
successively through alternate rows of fixed and moving blades, being
expanded down to a condenser pressure of about 1 lb. per square inch
absolute. The Curtis turbine is somewhat simpler
than the Parsons, and consists of elements each of which has at least
two rows of moving blades and one row of stationary. The bucket
velocity is lowered by fractional velocity reduction. Both the Parsons
and Curtis turbines are suitable for driving dynamos and steamships
directly. In efficiency, lightness, and bulk for a given power, they
compare favorably with reciprocating engines.