FE mechanical

relationship between P1, P2, V1, V2, and k

(P1/P2)=(V2/V1)^k

Equation of state for an ideal gas

(P1v1)/T1=(p2v2)/t2

Molecular weight

(mRT)/(PV)

Prefix M as in Mega

*10^6

Prefix G as in Gega

*10^9

For which type of process is the equation dQ=TdS valid? A)irreversible B)isothermal C)reversible D)isobaric

C) reversible Since the sides are separated by an equal sign, the process must be reversible. For irreversible: dQ<Tds

Otto cycle

Describes the internal combustion engine.

Temper

Description of the amount and type of processing done to a material at the mill, including cold work and thermal treatments

Force of drag equation

F=.5*Coeff of drag*density*velocity^2*area

Standard equation for calculating future worth (F), when given the annual rate of return (I) and the present rate (P).

F=P(1+i)^n

Gibbs phase rule

F=c-p+2 F=intensive degrees of freedom=variance P=# of phases C=components Factors=2+#of components-#phases

What is the origin of the energy conservation equation used in flow systems?

First law of thermodynamics

Work

Force x Distance DeltaPE+deltaKE

Tempering

Heating metal to a precise temperature below the critical point. Often done in air, vacuum or inert atmospheres Used to alter: hardness, ductility, toughness, strength, structural stability

Annealing

Heating steel to a specific temperature and then cooling at a very slow and controlled rate -softens a metal for cold working -improves machinability -enhances electrical conductivity -restores ductility Annealing used for steel but other metals can be subject to solution annealed

Diesel cycle

Reciprocating internal combustion engine

cold working

The plastic deformation of a metal at a temperature below that at which it recrystallizes.

Thermal efficiency of a power cycle

The ratio of useful work output to the supplied input energy

Maximum work obtained from a cycle is dependent on...

The temp of the local environment

Dalton's law of partial pressure

The total pressure of a gas mixture is the sum of the individual gases' partial pressures

Four processes for an Ideal, reversible Carnot cycle

Two isentropic and two isothermal processes

Work hardening/strain hardening

Use of permanent deformation to increase the strength of the metal. Aka cold work

Vector magnitude

Vector length (hypotenuse)

Unit vector

Vector with a magnitude of 1. Sometimes called a direction vector

Carnot cycle

a cyclical process that uses only reversible processes, the adiabatic and isothermal processes

extensive property

a property that depends on the amount of matter in a sample. Ex: mass and volume

isothermal process

a thermodynamic process that takes place at constant temperature

Specific enthalpy

h=u+pv

isentropic

having equal entropy

potential energy

mgh

Thermal efficiency for a Carnot engine formula

n= 1- (Tc/Th)

amorphous

no clearly defined shape or form

second law of thermodynamics

the entropy of the universe is always increasing. Impossible for a sys working in a complete cycle, to, as its sole effect, to transfer heat from a body at a given temp, to a body at a higher temp.

Hot working

when the deformation is carried out above the recrystallization temperature.

Equation for natural frequency

wn= sqrt(k/m)

Pump work equation thermo

wpump= h(in)-h(out) h=u + pv

kinetic energy

.5*m*v^2

Density of water

1 g/cm³ or 1000 kg/m3

Liters to m3

1 m^3=1000 liters

How to find Miller indices

1) Determine intercepts of Facebook 2)take reciprocals of coordinates 3)clear fractions 4) Reduce to lowest terms

Surface area of a sphere

4*pi*r^2

1 psi to pascal

6894.76 pascals

Annuity definition

A fixed sum of money paid each year

Oxidation

Absorption of oxygen. Material loses electrons

Fouling

Accumulation of unwanted material on sold surfaces

intensive property

Aka a bulk property. It is a physical property of a system that does not depend on the systems size or amount of material in the system.

Which cycle is the most efficient? Carnot, Brayton, diesel, otto

Carnot, b/c it is completely reversible

Brayton cycle

Constant pressure heat engine. intake, compression, combustion, and exhaust

Vector curl

Curl is a vector operator that describes a vector field's vorticity (rotation), at a point

Hydraulic diameter equation

Hydraulic D= (X-sectional area)/(wetted perimeter)

Entropy change for an adiabatic and reversible process

Net entropy change=0

Adiabatic

No heat exchange

isentropic process

No heat flow and reversible. Adiabatic process not necessarily reversible.

Units of Reynolds number

None

Period from k and m

Period=2*pi*sqrt(m/k)

Metal changes how when hot worked?

Produces a fine grained product Removes strain hardening Combines of annealing and cold working

1st law of thermodynamics

Q-W=delta U

Relative humidity

Ratio of water vapor pressure to saturation water pressure

Creep

Sometimes called cold flow. The tendency of a solid material to move slowly or deform permanently under the influence of mechanical stresses._