ORNL-TM-0269

Page 1


-LEGAL

P I -

This m p r t was prepored

06

brhalf of tha Commission:

Mnkrr any warronry or reprorent&tion, expressed completeness,

any

or urefulnetr of the inform&ian

informotion.

---

on occount of Covernmnt sponrotad work.

nor ths Commission, nor any person acting on

A.

NOTICE

apporotur.

M

implied,

Neifhsr

the

United Slates,

with r e r p e t t o tha

~ctmocy,

contoined in tlrh report, or that the

“$8

of

method, or pracers d i n c b s e d in this mpott moy not rnktnpe

privately owned rights; or

8.

Aa+umcr any Itabllttiea w i t h respect ta the use of, mr fm doquger reauhing from the vse of

ony inlarmotion, apporofus, method, or prooars disclosed

A s w a d in the ebavs, ‘‘pe,sM actnng contmctw of the C a m m i r r ~ a n , r or

on bah-lf

in

thra report.

04 tha Commic6ton” fncludeb any employee

01

cmplayee of such eontracfor, IO the extant thut such employee

contfmc#w of the Commlmion, or employee of such controcior prmp<mws, disssminatcr,

provides occess to, rrny informottm pvrrvont t o h r a mmploymant of tontcoct wtth the Commirrron, or h i s employment with such contractor.

i i

i t


-1-

Introduction

me ix A ) .

f the riser (see


R i t w x CaLcylatiicsns ( coat h u e d ) ?

Where:

E[

-

= height of r i ~ e r f t (see Fig. I)

- lb/ft2

t?lP = pressure drop i n heat exchanger

a t

D

t a r p e r a t w e drop i n heat exchanger

fz

diameter of riser

- ft.

OF.

hk = loss due to el1st exftanh eat of reactor, e x i t and ea% of heat

- 1.6 velocity heads. Q = power output - y46,ooo Btu/sec 2 exchanger

&E = accel.

af g r a v i t y

C = specific heat

-

-

32.2 f t / s e c

0.52 Btu 'lb

P 1 = 20 f t (see' Ffg. I)

-

OF

i c t i o n factor * .02 0 = temperatwe coefficient of d e n s i t y 3 p = degsity of fuel = 123 1 b / f t

-

0.0121 lb/ft3

- OF

For an e i g h t f o o t diameter reactor t h e volume of t h e piping w i l l be

f o r each value of

D

EL&

H*

AP

and Qt

this

VOL

will be a min-Jslum a t same ~ & u e of

Ffg. 33 is a p l o t of p i p i n g volume veratls rises height for

At

= 2QQo and

values of n p of 10, 20, 30, 40, lb/ft'. Simflm pxots were made far 25Uo. The min value8 of g volume and &e associated r ts and d i & e t e r s are ed against heat ex& pressure drop i n Figs. I11 and

IV.

Heat Exchanger C,;lculations

On the baBis t h a t t h e heat exchanger is of the counterflow tube and shell

desTgn with the fuel i n t h e tubes tuLd t h a t the Mussel$ number over the range


-3-

Eeat Exchanger Galcdateons (continued w e derive the follow

inwestigafed I s Golastant and e q u a l t o k'",

ships (see Appendix B)).

LN = 286.5 Q k

At,

The v a l w e of t h e heat exchanger is:

'HE.

'tubes

Where :

L = length of tube

-

+

'Header

ft

N = nmber of tubes K = %herma1 conductivity of fuel.

3 . 5 Btu/hr

$t %enqeraturedrop in heat exchanger. OF &ta = average temperature differential. 0F = tube inside dia.

-

.05 f t .

= v i s e a s i t y of f u e l =

Q = heat output. C

P

IL-

p =

lb /hr

0.3.74

3tu/sec

specific heat of f u e l .

density of fuel

- ft -

Btu/lb

ltP3 l b / f t 3

-

-

OF

ft

0

F

From this we can calculate L, N, and heat exchanger volume against heat

att,.

The tenrperatwes used were: f u e l entering the heat exchanger a t 1210%' and leaving at 960'~ to 3.035%. The wall temperature was tasken as g ng from 850' to 1050째, giving t h e exchanger pmssure drop Sol: differetrt

following temperature cond$tions:


Fuel E x i t

8%

nta

la35

3-77

1010

200

1-72* 5 160.0

T m s e ture

.

me t0t;al voluble i

Of the sy'stera is e

of the; heat exchmgei'p

..

A-t

At,

%he voluae of. tibe pisfog plus

1u-h riser diweter, heat exc

r tube length and number

of'Lubes, and t o t a l trolume of the Systen sgalnat riser height.

On the basis of this preLiminary i reactors do not seem to be very attractive. ptmps seems to be more than baL a u k r O P heat hanger tubes of heat exchanger tabes can be s An Investigation e higher than comparable forced the cast of a natt.mil. convect fuel circulation






-----..






14 c

Distribution 1-3.

DTIEJ AEC

4. M.

J. Sklnner


Turn static files into dynamic content formats.

Create a flipbook
Issuu converts static files into: digital portfolios, online yearbooks, online catalogs, digital photo albums and more. Sign up and create your flipbook.