Total power of electric heater selection calculationSelect power electric heaters are needed to meet the heating medium calorific value is to ensure that heaters for heating purpose, normal operation of choice.
because of the thermal efficiency of the electric heating is similar to 1, you could say: electric heater power is the heat.
1, power selection considerations
power calculation selection should take account of the following:
⑴ from the initial state, according to the set time requirements for heating medium to set temperature (temperature);
b in operating conditions heat enough to keep the medium temperature;
c should have some margin of safety, and generally the 1.2.
obviously, from ⑴, b opted for higher power, multiply is the power of magistrates or the safety margin.
2, calculated from the initial state of heating power required
(1) static fluid heating
(2) flow heating
(3) air duct heaters and pressure air heating
in the more than three-
p-gauge -- electric heater power required (KW);
Q -- container at a set temperature of heat dissipation (KW);
C1 - specific heat of the medium to be heated. (Kcal/(kg·℃)
C2 - container (System) of specific heat. (Kcal/(kg·℃)
M1 - quality of the medium to be heated. (Kg);
M2 - container (System), mass (Kg);
δ т - the difference between the set temperature and the initial temperature value. (℃);
t - from the initial duration of heating medium temperature to set the temperature required. (h);
F - heating medium flow, (maximum flow). (m /min);
S - heat . (m2) ;
q-loss - (insulating) material in the set temperature, the heat loss per unit area . (Kwh/m )
3. calculation of power needed to maintain temperature
in the formula:
p-dimensional - electric heater power needed to maintain temperature. (KW)
M1 - per hour increase in medium quality. (Kg/h)