Contents

- 5-2-1.Efficiency of the heater ” He” can be calculated by the equation below.
- 5-2-2.Heating efficiency Oe of the object to be heated can be calculated by the equation below.
- 5-2-3.Amount of heat J needed for heating can be calculated by the following formula.
- 5-2-4.Power Ph necessary to infrared heating can be calculated by the following formula.

The electrical energy (electric power) supplied from the power supply serves as electromagnetic waves, and jumps out of a heating element.

The electromagnetic waves exist wavelength of various kinds, but the most effective in heating is infrared rays.

The low- heat side (heating object) absorbs the electromagnetic waves radiated from the high-fever side (heater).

This is infrared heating.

### 5-2-1.Efficiency of the heater ” He” can be calculated by the equation below.

`He = (R + A + T) / P`

Rewriting

`He = (P - Hl) / P`

`He: efficiency of the heater
Hl: heat radiation loss from heater
R : reflection rate
A : absorption rate
T : transparent rate
P : power`

The “He” halogen heater boasts the best of efficiency in a variety of heater at about 85%.

### 5-2-2.Heating efficiency Oe of the object to be heated can be calculated by the equation below.

`Oe = A - Ol`

`Oe: heating efficiency of the heating object
A : absorption rate
Ol: heat radiation loss from the object to be heated`

Infrared absorption rate of each material – please refer to the “Science of the Infrared rays – 6. Absorption rate of infrared rays“.

### 5-2-3.Amount of heat J needed for heating can be calculated by the following formula.

`J = Ow x cv x Ot`

`Ow: the mass of the object to be heated
cv: specific heat at constant volume of the object to be heated
Ot: rising temperature width`

Specific heat of each material – please refer to the “Science of the Infrared rays – 10. The main materials Specific gravity,specific heat and thermal conductivity“.

### 5-2-4.Power Ph necessary to infrared heating can be calculated by the following formula.

`Ph = J / (He x Oe) / (P x Ar)`

`Ar: effective radiation area ratio`

When a large object to be heated compared to irradiation area of the heater Ar is 100%.

In the photo on the object to be heated is small compared to the irradiation area of the heater Ar is about 40%.