3B Scientific Stirling Engine D - Manual (Page 8)

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1. Safety instructions
When working with naked flames, there is always a
risk of fire and injury.
• Take extra care when handling naked flames
and molten wax.
• The Stirling engine may not be heated electri-
cally at the same time as it is being heated by a
candle. There is a risk of damage to the
equipment.
• When operating the Stirling engine using a
spotlight or sunlight, it is essential that care be
taken not to expose the red plastic components
to intense heat.
2. Description
The Stirling engine D is a fully functional model,
optimised for teaching purposes and intended to
demonstrate how thermal energy can be converted
to mechanical energy as well as for investigating
the Stirling cycle.
The displacement piston moves discontinuously
with a delay during heating and cooling of the
working medium, air. This emulates the ideal Stir-
ling cycle better than would be the case with a
continuously moving piston and also makes for
improved efficiency. The motion of the displace-
ment piston is controlled by the torque disc. When
heat is supplied from below, either by means of the
electric heater or by a candle flame, the displace-
ment piston precedes the working piston (mem-
brane) by about 100°. The optimum angle is tech-
nically dependent on the speed of rotation.
Heat can be supplied either by the built-in electric
hot plate, a candle or by focussed heat radiation
from the sun or by a lamp. The direction of rota-
tion depends on whether the heat is supplied from
above or below.
To record pV diagrams, the pressure in the working
cylinder can be measured by means of a hose at-
tached to the nozzle provided and the volume can
be determined by attaching a thread to the hook
on the connecting rod in order to measure the
stroke of the working piston.
3. Scope of delivery
1 D-series Stirling engine U8450450
1 Set of transport packaging (foam plastic block,
rubber band and retaining rod)
4. Accessories
Supplementary set for Stirling engine D
U8440455
The supplementary set for the D-series Stirling
engine provides accessories necessary for construct-
ing sensors. The set consists of the following:
1 Base plate for assembly of displacement sensor
(U11371)
1 Knurled screw for attaching the base plate to the
stand
1 Stem with a magnetic base for the displacement
sensor
1 Silicone tube for attaching a relative pressure
sensor, ±100 hPa (U11321)
1 Set of threads with suction cup
2 Weights with hook, both 20 g
5. Technical data
Heater voltage: 8 – 15 V, 1.5 A
Gas volume: 330 cm³ – 345 cm³
Speed: 30 – 100 rpm
Dimensions
not including rotor:
260Ч185Ч330 mm 3
Rotor: 400 mm
Weight: 2.2 kg