Flashcards in General Deck (22):

1

## What cladding is used in AGRs (Advanced gas cooled reactor)

### Stainless steel

2

## What gas is used as the coolant is AGRs

### Carbon dioxide

3

## What is the order of temperature magnitude for the coolant, fuel and cladding along a cooling channel

### Fuel > Cladding > coolant

4

## Equation for total power generated in cooling channel

###
P = mdot c (Tco - Tci)

co coolant out

ci coolant in

5

## Form of non dimensional temperature equation in terms of Tci Tco and T

### θ = 2 ((T - Tci)/(Tco- Tci)) - 1

6

## Coolant temperature at mid channel equation

### Tc1/2 = 1/2(Tci + Tco)

7

## For what shape does the minimum volume bare core occur

### Spherical

8

## Flux equation for spherical geometry

### Flux = A/r sin Br

9

## Assumptions used in the reactor kinetics equations (for the lumped models of the behaviour of a source free reactor)

###
No spatial variation in behaviour

In real life the reactor core is highly heterogenous

Only one type of precursor

In real life there are a large number of them with varying production rates and half lives

10

## Any potted in in hour equation graph

###
P = -λ

ρ = Λp + β

11

## What does the prompt jump approximation assume

### That the neutron population remains in equilibrium with the precursor population

12

## Why is restart impossible impossible for a period after shutdown

### As the Xe population will rise, peak then fall. For a period it will be sufficiently high that peak activity loss to axe poisoning will be greater than the excess reactivity available (from the control rods)

13

## Fuel utilisation equation for M batch cycle

### B = MTm where Tm = steady state batch time

14

## What ICRP stands for

### International commission on Radiological Protection

15

## 3 criteria laid down by ICRP

###
Don’t adopt practice unless risks are outweighed by the benefits

Exposures kept as low as reasonably achievable

Dose equivalents to individuals can’t exceed certain values

16

## Methods of protection against external radiation (3)

### Time, distance, shielding

17

## Purpose of dose limits

### To prevent: short term effects (burns), long term effects (cancers) and genetic effects.

18

## What is the dose limit for registered radiation workers

### 20 mSv/yr

19

## Assumptions on which dose limits are based

###
No threshold dose exists and any dose involves a proportionate risk of cancer

Doses received on separate occasions act cumulatively

20

## Equation for the shield flux (flux at the edge of shielding)

###
φ’ = φ e^[-αd)

Φ unshielded flux

α attenuation coefficient

d distance

21

## Equation that helps you find the criticality condition

###
α^2 + β^2 = Bm^2

Alpha and beta found by solving each variable in the differential equation.

22