OCR Text |
Show Refinery Heater Simulation by Hottel Zoning Hethod 15 and natural convection, c . Sum of mass-enthalpy fluxes of flue gases entering gas zone "k", d. The heater combustion released in the gas volume "k". For gas zone "k" the first derivative with respect to temperature is stored in the diagonal cell of the matrix: B. One way radiative fluxes from gas volume zone "k" to all zones (gas, refractory, tube sink), one by one, b. Convective heat flux from gas zone "k" to contiguous surface zone(s), c. Sum of mass-enthalpy fluxes of flue gases leaving gas zone "k". For refractory zone "m", the energy entering (non-diagonal terms) includes: B. Radiative fluxes from all other zones (gas, refractory or sink), one by one to gas zone "m", b. Convective heat flux from adjacent gas volume to refractory surface "m". For refractory zone "m", the energy leaving (diagonal terms) includes: a. Radiative fluxes from surface "m" to all other zones (gas, refractory and tube sink), one by one, b. Convective heat flux from "m" to adjacent gas volume zone, c. Convective heat flux leaving "m" through setting. Insert the now known refractory and gas zone temperatures into energy balance equations on the each sink zone including a term for heat loss for through refractory behind the tubes to compute the sink net flux E. Box Heater Test The test furnace was a Naphtha Reboiler Heater (Figure 9) fired by 4 burners on each end wall (XY plane), with 2 row of shock tubes and a single row of tubes on each side wall (YZ plane). There is symmetry with respect to a XY plane at the midsection in the Z direction of firing . Pipes were placed into the side wall |