**Another Lugano dummy run temperature check.**

For an internally heated tube/rod type shape there is for a section in the middle limited lateral heat conduction since the temperatures on both sides of the section have temperatures close to the temperature of the section itself.

This means that most heat in such a section must be radially dissipated by convection and radiation.

Using the measurement information provided by Para for his rod in an attachment to his post #634, we can use his data for a section temperature verification of the Lugano dummy run.

For this analysis we use Para's first measurement at time 20.59 for section 3 (near the middle).

We have the following data :

Total heater power-----------------85.41 Watt

Heater coil length---------------------6.1 cm

Section length (section 3)---------- 2.5 cm

This means that (2.5/6.1) x 85.41 = 35.0 Watt is dissipated by the heater in section 3

From this power we subtract the convective power.

For calculating the convective power we use the method as shown in the Lugano report since that the method was found to be in close agreement with CFD simulations.

(see post #382)

The calculated convective power then becomes 10.87 watt

Thus 35.00 - 10.87 = 24.13 Watt needs to be get rid off by radiation and some (limited) lateral conduction.

The dimensions of Para's rod section 3 are

Diameter------------0.025 Meter

Length----------------0.025 Meter

Thus the area is Pi x .025 x .025 = 0.001963 square meter

The dissipated (mostly) radiated heat per area for section 3 is then 24.13/0.001963 =

**12292 Watt/square meter**

We are now comparing this to the disspated heat per area of area 5 of the Lugano ECAT during the dummy run.

Following the drawing in the patent the heater winding under the ribs is 8 windings with a diameter of about 1 cm. (length under the ribs is 20 cm)

If we calculate this through for the dummy run then the dissipated power under the ribs becomes 290 Watt

Power per section of 2 cm then becomes (2/20) x 290 = 29 Watt

Convection is the calculated 14.96 watt (see post #393) but must be multiplied by the convective correction factor for the ribs.

This correction value was found to be 0.752 and is due to the less efficient convection which is caused by the ribs being close to each other.

The convected power of section 5 is then 14.96 x 0.752 = 11.25 Watt

Thus the dissipated radiated (and some lateral) heat of section 5 becomes 29.00 - 11.25 = 17.75 Watt.

The effective radiative area of section 5, rib area and view factor applied, is 0.001504 square meter.

(For an explanation of effective area see post #20)

Thus the dissipated radiated and minor lateral heat for section 5 during the Lugano dummy run becomes 17.75/0.001504 = **11801 Watt/square meter**

The difference between both the 12292 Watt/square meter from Para's rod and the 11801 Watt/square meter for section 5 of the Lugano dummy run is only 4.2%.

This means that the surface temperature of section 5 of the Lugano dummy run must be close to the value wich Para measured for section 3 of his rod, the value being 451.3 degree C.

The reported value in the Lugano report for section 5 during the dummy run was 454.0 degree C, indeed close to the value of 451.3 degree which Para measured.

Thus the in the Lugano report reported value of 454 degree C for section 5 of the dummy run must be (close to) correct.