A _c

Circumferential flow area

A _w

Wick cross-sectional area

C _p

Specific heat of vapour, constant pressure

C _v

Specific heat of vapour, constant volume

D

Sphere density in Blake-Kozeny equation

H

Constant in the Ramsey-Shields-Eotv s equation

J

4.18 J/g mechanical equivalent of heat

K

Wick permeability

L

Enthalpy of vapourisation or latent heat of vapourisation

M

Molecular weight

M

Mach number

M

Figure of merit

N

Number of grooves or channels

Nu

Nusselt number

Pr

Prandtl number

P

Pressure

?P

Pressure difference

?Pcmax

Maximum capillary head

?Pl

Pressure drop in the liquid

?Pv

Pressure drop in the vapour

?Pg

Pressure drop due to gravity

Q

Quantity of heat

R

Radius of curvature of liquid surface

Ro

Universal gas constant = 8.3 10 ³ J/K kg mol

Re

Reynolds number

Re _r

Radial Reynolds number

Re _b

A bubble Reynolds number

S

Volume flow per second

T

Absolute temperature

T _c

Critical temperature

T _v

Vapour temperature

?T _s

Superheat temperature

T _w

Heated surface temperature

V

Volume

V _c

Volume of condenser

V _R

Volume of gas reservoir

W _e

Weber number

a

Groove width

a

Radius of tube

b

Constant in the Hagen-Poiseuille Equation

c

Velocity of sound

d _a

Artery diameter

d _w

Wire diameter

f

Force

g

Acceleration due to gravity

g _c

Rohsenhow correlation

h

Capillary height, artery height, coefficient of heat transfer

k

Boltzmanns Constant = 1.38 10 ^?23 J/K

k _w

Wick...