-
-
Pressurissed water reactor
-
f forms radiation
Material: α (helium nucleus) and β (electron) particlesElectromagnetic: γ rays
-
Half life equation
N = N0 e–λt
-
Fast Reactor
- utilizes fast neutrons (> 1 Mev)
- needs > 10% fissile material (Pu-239, U-233)
- smaller in size; heat removal is challenging
-
Thermal Reactor
- utilizes slow or thermal neutrons (< 1 eV)
- enrichment from 0.7% to 90% U-235
- 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
-
U-235 is the only natural fuel for _____ ractions
thermal
-
fission of U-235 releases about ________ per atom
200 M eV
-
Reactor power equation
- P = Φ NT σf W
- Where Φ = average neutron flux across core (neutrons/cm2-s)
- NT = total fuel nuclei in core
- σf = thermal cross section (cm2)
- W = energy released per fission
-
-
equation for a window paralell to wall
R0*Rp/(Ro+Rp)
-
-
R= 1/l
thermal resistance per length, per unit area
-
Q
- Heat Flow
- W/m2Btu/ Hr-ft2
-
K, A, dt, dx, R (group prject)
- conductance
- area
- change in temperature
- distance through material
- r*l, thermal resistance
-
-
Ro, R, Rp
- L0/(K0*A)
- dx/(K*A)
- Lp(Kp*A)
-
3 types hydro energy
- Impoundment- potential energy
- Run-off river- kinetic energy, 1/2m(V2-v2)
- 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/s2 X 1 m/ 1 s
- = 9800 Joules/s
- = 9800 W
- = 9.8 kW
-
-
PE hydro
PE=mgh=PE/m3= ρgZ
-
Power generated in Hydro
Power = Potential Energy X Volume/(Time X Efficiency)
PowerPE = PE X Flowrate X Eff
-
Penstock
- Penstock-moves 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
- Non-dispatchable
- 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
-
ρair 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
(v3)avg
-
Turbines have _____ blades
2-3 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
-
cut-in
Wind speed at which usable power produced
-
Cut-out
Wind speed at which unit brakes
-
Rated
Minimum speed to produce rated power
-
A 3 MW turbine requires the following non-renewable 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 in-line 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 must-take while load is ramping down
|
|
