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VIII.2.1.2 Subsystem of reciprocal of thermal resistances on heat plate circumferential<br />

outer surface<br />

This subsystem is based on Eq. (3.24). Inputs to this subsystem are listed below:<br />

Input port number Input Unit<br />

1 Temperature on heat plate top °C<br />

2 Ambient air temperature °C<br />

The output is the reciprocal of the thermal resistances on heat plate circumferential<br />

outer surface.<br />

T_PlateTop(C)<br />

In1<br />

1<br />

2<br />

In2<br />

T_amb(C)<br />

g*CircumfHeight^3<br />

*air_ß/V2*Pr<br />

(8.389e6)<br />

60<br />

|u| u^0.25 4.78e-3<br />

Ra^0.25<br />

- 202 -<br />

0.59*PlateCircumf<br />

Diamtr*Pi<br />

*AVRGED_air<br />

thermal_Conductvty<br />

(0.02632)<br />

1<br />

Out1<br />

h*A<br />

Figure VIII. 5 Heat plate circumferential outer surface subsystem<br />

VIII.2.2 Water surface heat transfer subsystem<br />

The water surface heat transfer subsystem is based on Eq. (3.39) but output is the<br />

reciprocal of the resistance. The total mixed Nusselt number is calculated by Eq. (3.38).<br />

Inputs to this subsystem are listed below.<br />

Input port number Input Unit<br />

1 Water temperature °C<br />

2 Temperature of inlet to the chamber from ADU °C<br />

3 Velocity of inlet to the chamber m/s<br />

4 Portion of impact area to total water surface area Decimal<br />

For the water thermal balance subsystem, it only considers the steady status so to<br />

calculate the stable water temperature as discussed in Chapter 3. The inlet uses the<br />

steady flow from ADU and inlet temperature is also of that. The input 3 is actually the<br />

average velocity of airflow at the outlet of the connecting duct and in the HADT and

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