PHYSICAL CONSTANTS IN SI UNITS

Absolute zero of temperature – 273.15 °C

Acceleration due to gravity - g 9.807 m/s2

Avogadro’s number - NA 6.022x1026 /kmol

Base of natural logarithms - e 2.718

Boltzmann’s constant - k 1.381 x 10–26 kJ/K

Faraday’s constant - F 9.648 x 107 C/kmol

Universal Gas constant - R 8.3143 kJ/kmol K

Permeability of vacuum - μo 1.257 x 10–6 H/m

Permittivity of vacuum - εo 8.854 x 10–12 F/m

Planck’s constant - h 6.626 x 10–37 kJ/s

Velocity of light in vacuum - c 2.998 x 108 m/s

Volume of perfect gas at STP 22.41 m3/kmol

Purpose Of Heat Exchanger

1. To heat or cool a stream flowing from item of equipment to another. The stream may be gas liquid or mixture of both.

2. To vaporize a liquid stream.

3. To condense a vapor stream.