| dc.description |
The vortex tube has no moving parts and its
makes it an attractive form of refrigerator when a source of
compressed air is available. The drawback is that this device
has a low efficiency.
The proposed application involves passing compressed
air, from a jet engine, through a precooler and a vortex tube to
the ventilated suit.
Investigations show that the temperature of the air
entering the ventilated suit is decreased as engine compression
ratio and precooler efficiency are increased.
Increase of the aircraft's forward speed will result
in decreased cooling until a maxim= Mach number is reached above
which the ventilated suit cooling requirement, of 115o F, can no
longer be satisfied.
The maximum permissible Mach number, for an aircraft
flying at sea level under the maximum ambient tropical temperature
of 45°C, has been calculated over a range of compression ratios,
3 - 15 and precooler efficiencies, 75 - 100 per cent. These
results are plotted in figures 6 and 7.
It is found that a practical application requires a
precooler efficiency of not less than. 80. per cent. |
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