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KURENAI : Kyoto University Research Information Repository

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particularly in the case of a<br />

forced convection flow given<br />

fluid with a similar Prandtl<br />

In a laminar flow range,<br />

fluid to fluid simulation. The correlation for<br />

by Eq. (37) shows that it is desirable to use a<br />

number.<br />

the heat transfer correlation gives<br />

kR .<br />

hR=dR , (40)<br />

whereas for turbulent flow of fluid such as water<br />

kRpuRd0.83<br />

hR=dRR<br />

uRPrR .(41)<br />

RR)<br />

It is evident that Eqs. (40) and (41) impose quite different constraints on<br />

operational and design parameters with respect to Eq. (35). Furthermore,<br />

Eqs. (34), (35), and (41) require that the ratio of the Reynolds number to be<br />

close to one. For a scale model this may result in higher model velocity and<br />

very high model power. Because of this, the similarity condition based on<br />

the Biot or Stanton number should be carefully evaluated.<br />

VI.2.3 Scale Model with Same Fluid<br />

A special case of a scale model with the same fluid is now examined<br />

For this case all the property ratio groups can be set as unity. Thus<br />

Then<br />

PR<br />

the<br />

PCp R=<br />

similarity laws developed<br />

Reference Velocity Ratio<br />

uR =I<br />

• aR 2 1/3<br />

qoR d<br />

R~R<br />

Wall Conduction Depth Ratio<br />

diR<br />

(pCp)R = kR = uR = PrR = 1<br />

above reduce to the following equations.<br />

(42)<br />

(43)<br />

~'R<br />

= dR= uR . (44)<br />

341

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