Eclipse Combustion ImmersoJet Series, Руководство по конструкции

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Eclipse ImmersoJet v2.20 Design Guide 330, 10/02
System Design
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Designing a burner system is a straightforward exercise. The
steps are:
1. Burner model selection.
a. Determine net input required for the tank or process
b. Select tube efficiency
c. Calculate gross input required
d. Select burner model
2. Tube design.
3. Control methodology.
4. Ignition system.
5. Flame monitoring system.
6. Combustion air system: blower and air pressure switch.
7. Main gas shut-off valve train.
8. Process temperature control system.
Determine the net input required to the tank
The net input to the tank is determined from heat balance
calculations. These calculations are based on the heatup and
steady-state requirements of the process, and take into account
surface losses, tank wall losses and tank heat storage. Detailed
guidelines for heat balance calculations are in the Eclipse
Combustion Engineering Guide (EFE 825).
Select tube efficiency
The efficiency of the tube is the net heat input to the tank
divided by the heat input to the tube. Efficiency is determined by
the effective tube length. The diameter of the tube has little
influence on the efficiency. At a given burner input, the net input
to the tank is higher for a longer tube than for a relatively short
tube.
It is customary to size conventional immersion tubes for 70%
efficiency, a reasonable compromise between fuel economy and
tube length. However, small diameter tubes occupy less tank
space than conventional tubes, so their length can easily be
increased to provide efficiencies of 80% or more.
Calculate the gross burner input
Use this formula to calculate gross burner input in Bth/hr:
D
ESIGN
S S S S S
TEP TEP TEP TEP TEP
1 1 1 1 1:::::
B
URNER
M
ODEL
S
ELECTION
net output to tank
tube efficiency
= gross burner input
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