Transcript Cryo-Tracker™ Level, Temperature, and Mass Gauging Fluid

Cryo-Tracker
Level, Temperature,
and Mass Gauging Fluid
Sensors
1
Behavior of Sub-cooled
Propellants in Room Temp.
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Fig: Liquid Nitrogen
unloaded from a
small a Dewar Flask
to a bucket in a
laboratory.
Dewar Flask
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Fig: A 25 l liquid
nitrogen laboratory
Dewar flask.
Inner wall linings
are silvered to
reduce heat
leakage.
Flexible Sensing Probe
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Probe is made of
series of polyimide
layers of thickness
0.0254 mm.
Rakes made of
stainless steel
tubing, wire, and
phenolic insulators
weigh (6.70 g/cm).
Internal Structure of
Cryo-Tracker
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Silicon diode sensors
incorporated with
the probe.
Conductor Traces
which constitute the
rake of the tempelement
Installed Cryo-Tracker Probe
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Cryo-Tracker probe
60 ft. long.
2.5 cm wide.
containing 26 silicon
diode sensors.
It’s weight is less
than 0.59 kg.
Stratification of Sub-cooled
Propellants
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The heat leak
causes the
propellant to warm
and stratify due to
natural buoyancy
forces.
Cryo-Tracker
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Initially designed for
incorporating in the
propellant vessels of
reusable launch
vehicles.
Purpose of Cryo-Tracker
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For knowing the amount of propellant
loaded in.
For knowing the liquid & ullage
temperature.
For knowing liquid level.
Mass Gauging Method
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The entire liquid and ullage temperature
profile is first obtained.
Tank pressure can then be used to
calculate a liquid density profile.
Liquid density profile is integrated over
the known tank volume.
Dual-Purpose Probe.
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Temperature measured
using silicon diode
sensors.
Liquid level detection
accuracy is a function of
the sensor spacing.
For 12 inch sensor
spacing, the overall
liquid level accuracy is
± 6 inches.
Performance
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Consistent thermal
response can be
seen between the
sensing elements in
a dual-element
probe when it’s
thermal-cycled in
liquid nitrogen.
Hot-Fire Test
(anomaly condition)
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The probe is also
capable of measuring
transient fluid
temperature changes.
Figure : Tracking the
rapid change in liquid
oxygen temperature
when warm gases
injected into the tank
mixed the contents.
Advantages of Cryo-Tracker
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Operating Costs
Accuracy
Reliability
Safety
Efficiency
Scalability
Flexibility
Commercial Applications
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Cryogenic storage and transport tanks
Home oxygen vessels
Medevac helicopter and military field
hospital oxygen-generating systems
Automobiles running on liquid hydrogen
or liqufied natural gas