ESCI 3201
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Pressurissed water reactor

f forms radiation
Material: α (helium nucleus) and β (electron) particlesElectromagnetic: γ rays

Half life equation
N = N_{0} e^{–λt}

Fast Reactor
 utilizes fast neutrons (> 1 Mev)
 needs > 10% fissile material (Pu239, U233)
 smaller in size; heat removal is challenging

Thermal Reactor
 utilizes slow or thermal neutrons (< 1 eV)
 enrichment from 0.7% to 90% U235
 greater flexibility w.r.t. moderators, coolants, fuels
 can be large or small in size

components of thermal power reactor
 fuel pellet
 fuel rod
 fuel assembly
 core
 moderator/coolent
 shields
 pressure vessle

nuclear provides ______ to the US annually
8 quads

two primary concerns of fission
 Heat removal after shutdown (due to alpha and beta release)
 Handling of spent fuel after removal

K factor
K factor describes effectivity of plant

Most impottant fission product
Xenon


Fission energy: reduction of energy on resultant fission
1/40 of electron volt

2 possible reaction after adding nuetrons
 absorption capture
 absorption fission

3 parts of Nuclear fission
 nuetrons are key
 self sustaining fission chains
 critial : steady rate of chain reaction, subcritical: decreasing reaction rate, supercritical: increasing reaction rate

U235 is the only natural fuel for _____ ractions
thermal

fission of U235 releases about ________ per atom
200 M eV

Reactor power equation
 P = Φ N_{T} σ_{f} W
 Where Φ = average neutron flux across core (neutrons/cm2s)
 N_{T} = total fuel nuclei in core
 σ_{f} = thermal cross section (cm2)
 W = energy released per fission


equation for a window paralell to wall
R_{0}*R_{p}/(R_{o}+R_{p})


R= 1/l
thermal resistance per length, per unit area

Q
 Heat Flow
 W/m^{2}
 Btu/ Hrft^{2}

K, A, dt, dx, R (group prject)
 conductance
 area
 change in temperature
 distance through material
 r*l, thermal resistance


R_{o}, R, R_{p}
 L_{0}/(K_{0}*A)
 dx/(K*A)
 L_{p}(K_{p}*A)

3 types hydro energy
 Impoundment potential energy
 Runoff river kinetic energy, 1/2m(V_{2}v_{2})
 Pumped hydro

Impoundemnt systems are dependant on ____
Carno efficiency cycle

Power available from 1 cubic meter of waterfalling through 1 meter every second:
 P = Energy per unit of Time
 = mgh
 = 1000 kg X 9.8 m/s^{2} X 1 m/ 1 s
 = 9800 Joules/s
 = 9800 W
 = 9.8 kW


PE hydro
PE=mgh=PE/m^{3}= ρgZ

Power generated in Hydro
Power = Potential Energy X Volume/(Time X Efficiency)
Power_{PE} = PE X Flowrate X Eff

Penstock
 Penstockmoves water from reservoir to turbine (pipes)
 Radial in, axial out
 Runner
 scroll case


tailrace
flow after the dam

forebay
flow before the dam

AC
alternating current, 3 phases

DC
direct current, converter station

WInd energy basics
 Solar Driven
 High variability, poorly correlated to loads
 Nondispatchable
 No economic storage of wind energy
 Power proportional to cube of wind speed

Wind energy equation
P(v) = ½ρAv3
 P(v) = power, in watts
 A = area perpendicular to flow, in m2
 ρ = density of fluid, in kg/m3
 v = velocity of fluid, in m/s

wind speed generally ______ wit height
increases

ρ_{air }value
1.226 kg/m3 at 15 °C (288°K) and 1 atmosphere

warm air _____ available power by_____
reduces, 6%

Cold air ______ power by ______
increases, 24%


Average power of wind
(v^{3})avg

Turbines have _____ blades
23 blades

Lift
 Pocket of low pressure on downwind side
 Pocket pulls blade toward it

Lift is up to ______ than drag
10X's stronger

Yaw control
keep blades perpendicular to wind

cutin
Wind speed at which usable power produced

Cutout
Wind speed at which unit brakes

Rated
Minimum speed to produce rated power

A 3 MW turbine requires the following nonrenewable resources:
 335 tons of steel
 4.7 tons of Cu
 3 tons of Al
 2 tons of rare earth elements

For turbines in a line perpendicular to prevailing winds: spacing of wind towers
Towers usually spaced 3 to 5 rotor diameters

For turbines inline with prevailing winds: spacing
Towers usually spaced 5 to 9 rotor diameters

Nth row eficiency equation for wind turbines
 F≈e ^{2N/R2}
 Where R = x/D
 D = rotor diameter

Baseload fleet
minimum generation limits

reserve requirements
potential increase in wind generation

baseloading requiremnets
at a time when baseload unit regulation will be needed more than ever

ramping
wind ramping up and considered musttake while load is ramping down