Technical Symbols (CalQlata)

a

Maths: length

a

Hydrodynamics & Engineering: acceleration

see also Derivative Symbolism at the bottom of this page

aₒ

Physics: Bohr radius

ap

Electrical: apparent power

A

Maths: angle

A

Engineering: area

A

Engineering: amplitude or deflection (dynamic)

Aƒ

Engineering: amplification factor

Atm

Engineering: atmospheres

b

Maths: length

b

Engineering: breadth (width)

B

Maths: angle

B

Engineering: buoyancy

c

Maths: length

c

Dynamics: viscous damping coefficient

c

Hydrodynamics: celerity

cp

Thermodynamics: specific heat capacity at constant pressure

cv

Thermodynamics: specific heat capacity at constant volume

Cp

Thermodynamics: Heat at constant pressure

Cv

Thermodynamics: Heat at constant volume

C

Temperature: Celcius or centigrade

C

Maths: angle & circumference

C

Electrical: capacitance

C

Engineering: coefficient

C

Fluids: Cauchy number

Ca or Cm

Hydrodynamics: added mass coefficient

Cd

Hydrodynamics: drag coefficient

Cᴸ

class

₵

Engineering: centreline

₠

clearance

d

Engineering: depth

d

distance

d

Time: day

e

Stress: strain

e

Maths: eccentricity

e

Physics: elementary charge

E

Stress: Young's modulus

E

Fluids: Euler number

E

Thermodynamics: total energy

ECF

Engineering: end cap force

Ef

Stress: flexural modulus

EI

Engineering: bending stiffness

ƒ

Fluid Dynamics: Colebrook's fanning friction factor
Note: see also dynamic viscosity (μ) below

ƒ

Engineering: frequency
Note: see also dynamic viscosity (μ) below

ƒⁿ

Engineering: natural frequency

F

Engineering: force

F

Temperature: Fahrenheit

F

Fluids: Froude number

g

gravitational acceleration

G

Engineering: shear modulus (modulus of rigidity)

h

Time: hour

h

Engineering: height

h

Thermodynamics: specific enthalpy

h

Stress: Weibull parameter

h

wind chill factor (kcal/m²/h)

h

Physics: Planck's constant

ħ

Physics: Dirac's constant

H

Engineering: composite second moment of area (product of I_xx & I_yy)

H

Thermodynamics: enthalpy

I

Engineering: second moment of area (moment of inertia)

I̊

Engineering: rotational (moment of) inertia

I

Electrical: current

J

Engineering: polar moment of inertia

J

Thermodynamics: mechanical equivalent of heat

Jͫ

Thermodynamics: mechanical equivalent of heat

k

Engineering: spring constant

k

Hydrodynamics: wave number

k

Engineering: bulk modulus

K

Temperature: Kelvin

K_c

Engineering: Keulegan-Carpenter number

KE

Physics: kinetic energy

ℓ

Engineering: part length

L

Electrical: inductance

L

Engineering: total length

Lon & Lat

Survey: longitude and latitude

m

Engineering: mass

mₑ

Physics: mass energy

mᵣ

Physics: rest-mass

ḿ

Engineering: slope

Whilst 'm' means slope in maths (e.g. y=mx+C), engineering has no standard symbol for 'slope'
CalQlata has adopted this symbol for a slope in engineering but differentiated it from the symbol for mass (m) by giving it an accent (a slope!)
(ḿ = height ÷ distance)

mn

Time: minute

M

Fluids: Mach number (fluid flow)

M

Engineering: moment

MBR

Engineering: minimum bend radius

MMC+

Engineering: maximum metal condition

MMC-

Engineering: minimum metal condition

n

number

p

Engineering: pressure

p

Hydrodynamics: period

p

Electrical: power

p

Work & Energy: Power, momentum

pdl

Engineering: poundal

pf

Electrical: power factor

pₒ

Work & Energy: Power (if used alongside pressure)

P

Engineering: pitch

PC

Fluids: pressure coefficient

PE

Physics: potential energy

Q

Fluids: quantity flow rate e.g.:
Q = volumetric flow rate (e.g. m³/s)
Q̊ = mass flow rate (e.g. kg/s)
Q̅ = molecular flow rate (moles/s)

Q

Electrical: charge

Q

Thermodynamics: heat energy

r

radius / inside radius

ɍ

radius of gyration

R

Temperature: Rankine

R

radius / outside radius

R & R̿

Electrical: resistance

R

Thermodynamics: gas constant (ideal gas)

Rₐ

Thermodynamics: specific gas constant (ideal gas)

Rᵢ

Thermodynamics: universal gas constant (ideal gas)

Rᴺᵒ

Fluids: Reynold's number

RPS

revolutions per second

RPM

revolutions per minute

R_v

Fluids: velocity ratio

s

Thermodynamics: specific entropy

s

Stress: primary stress

s

Time: second

S

Thermodynamics: entropy

S

Stress: principal stress

Ṡ

Stress: maximum principal stress

Ṣ

Stress: minimum principal stress

Ṩ

Stress: most damaging principal stress

S

Fluids: Strouhal number

SG

specific gravity (relative density)

t

time

t

Engineering: thickness
Note: when 't' is used for time in the same calculation, 'th' shall be used for thickness

T

Engineering: torque

Ṯ

temperature

u

initial velocity

U

Engineering: energy

U

Stress: utilisation

U

Thermodynamics: internal energy

Uᴷ

Thermodynamics: kinetic energy

Uᴾ

Thermodynamics: potential energy

v

Hydrodynamics & Engineering: velocity

see also Derivative Symbolism at the bottom of this page

v

Thermodynamics: specific volume

V

volume

V

vector

V

Electrical: voltage

w

Engineering: distributed load (per unit length)

W

General: width

W

Engineering: weight

W

Fluids: Weber number

W

Thermodynamics: work

x

distance (horizontal)

X

Electrical: reactance

y

Maths & Engineering: distance (vertical)

y

Engineering: distance from neutral axis

y

Engineering: deformation or deflection (static)

z

Hydrodynamics: distance (vertical)

Z

Fluids: head

Z

Electrical: impedance

Z

Engineering: section modulus

Ø

Diameter

α

Engineering: linear expansivity

α'

Engineering: square (area) expansivity

α"

Engineering: cubic (volumetric) expansivity

αᴿ

Electrical: temperature coefficient of electrical resistivity

α

angle (degrees)

β

angle (degrees)

γ

specific weight

γ

Thermodynamics: ratio of specific heats

ε

Engineering: efficiency

ε

Maths: error

ζ

Engineering: stability parameter

ζ

Dynamics: viscous damping factor (damping ratio)

η

Hydrodynamics: profile

η

Stress: damage ratio

θ

angle (degrees)

κ

Electrical: conductivity

λ

Engineering: thermal conductivity

λ

Physics: wave length

μ (or ƒ)

Engineering: friction coefficient
Note: ƒ is used where formulas also include dynamic viscosity

μ

Physics: magnetic field

μ

Fluids: dynamic viscosity
Note: also known as absolute viscosity

ν

Fluids: kinematic viscosity

ν

Stress: Poisson's ratio

ρ

Materials: density

ρᴹ

Chemical: molecular density

ρᴿ

Electrical: resistivity

ϵ

Engineering: surface roughness

σ

Fluids: surface tension

σ

Stress: equivalent and general stress

τ

Stress: shear stress

φ

angle (degrees)

φ

Engineering: phase angle

ω

angular frequency

Datum:

e.g. Ṯᴰ

A datum value is defined by a superscript capital 'D'. The example shown here is for temperature.

δ

variation or range

y

yocto (1E-24)

z

zepto (1E-21)

ɑ

atto (1E-18)

f

femto (1E-15)

p

pico (1E-12)

n

nano (1E-09)

μ

micro (1E-06)

m

milli (0.001)

c

centi (0.01)

d

deci (0.1)

da

deka (10)

h

hecto (100)

k

kilo (1000)

M

mega (1E+06)

G

giga (1E+09)

T

tera (1E+12)

P

peta (1E+15)

E

exa (1E+18)

Z

zetta (1E+21)

Y

yotta (1E+24)

₁

Fluids: in

₂

Fluids: out

₀ _to ₉

Engineering: sequencing

a

Engineering: anchor

ᵅᵛᵉ or v̅

average

note a bar above a letter (e.g. v̅) is sometimes used as an abbreviation for average in the calculators

a

Hydrodynamics: added mass

A, B, etc.

Engineering: end or position

ᶜ

Maths: angle in radians

ₑ

Stress: equivalent

fl

Engineering: fluid

h

Stress: hoop

h

Engineering: horizontal direction

ᵢ

Engineering: internal

ᵢ

Stress: index

l

Stress: longitudinal

m̂ or min

minimum

A 'ʌ' above any letter indicates a minimum value

m̌ or max

maximum

A 'v' above any letter indicates a maximum value

mm

Engineering: … about weak/strong axis

n

Stress: nominal

nn

Engineering: … about strong/weak axis

ᴺᵒ

Number (as in Reynolds, Euler, Mach, etc.)

ₒ

Engineering: outside / external

o

Stress: total

%

Engineering: packing

p

Stress: primary

P

Stress: principal

r

Stress: radial

t

Engineering: terminal

ᵀ

total

u

Stress: ultimate tensile stress

v

Engineering: vertical direction

w

Engineering: wall

x, y, z, etc.

Engineering: horizontal, vertical, etc. position or direction

xx, yy, zz, etc.

Engineering: … (about) fundamental axes (xx, yy, etc.)

xy, xz, etc.

Engineering: … (about) compound axes (xy, xz, etc.)

ỵ

Stress: minimum yield

Derivative Symolism

Hydrodynamics & Engineering: velocity and acceleration

In addition to the conventional symbols used for velocity ('v') and acceleration ('a'), CalQlata occasionally adopt the following mathematical symbols where improved recognition is assumed for groupings ('x' is provided as an example character, any character is equally valid):

velocity = ẋ
(i.e. the first derivative of displacement x)

acceleration = ẍ
(i.e. the second derivative of displacement x)