BOOT STRAP-REDUCED AMBIENT AIRCRAFT COOLING SYSTEMS

 

https://www.mesubjects.net/wp-admin/post.php?post=386&action=edit       Nomenclature of refrigerants

https://www.mesubjects.net/wp-admin/post.php?post=358&action=edit        Gas Refrigeration-1

https://www.mesubjects.net/wp-admin/post.php?post=483&action=edit       Q. Ans Air Refrigeration-2

https://www.mesubjects.net/wp-admin/post.php?post=415&action=edit         Q. Ans Refrigeration

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https://www.mesubjects.net/wp-admin/post.php?post=371&action=edit         Q. Ans Air Refrigeration-3

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BOOT STRAP AND REDUCED AMBIENT AIRCRAFT COOLING SYSTEMS

AIR REFRIGERATION

It is used in all the aircrafts. There are different cooling arrangements for the air conditioning of aircrafts. Boot strap and reduced ambient cooling systems are discussed here.

Boot Strap Air Refrigeration System: Two types

  1. Without evaporative cooling,
  2. With evaporative cooling

Second one is discussed below:

 

 

 

FIG. BOOT STRAP SYSTEM ON TEMPERATURE ENTROPY CHART

In this, there are two compressors, two heat exchangers and one turbine. Expansion turbine runs the second compressor..  In Boot strap, another water cooled heat exchanger is placed after the second heat exchanger.

 

Reduced Ambient Air Refrigeration System

 

Fig. REDUCED AMBIENT AIRCRAFT COOLING SYSTEM ON TEMP ENTROPY CHART

It uses two turbines and one compressor. Turbine 1 uses rammed air. The air from turbine 1 enters the heat exchanger. Turbine 2 uses air after the heat ex-changer for further cooling.

Turbine 1 has input and output points as 2 and 4.

Cooled air from turbine 1 enters the first Heat exchanger at point 4.

Heat exchanger has input at points 3 and 5.

CAUTION: RAMMED AIR IS FED TO TURBINE 1.

Turbine 2 has input and output points as 5 and 6.

Procedure of calculation is similar to the BOOT STRAP SYSTEM.