Thermal Analysis – Solutions: Active – Closed Loop Cooling – Page 3

  • Temperature management with air-air exchangers

>>Fans Only

The use of air-air exchangers requires a temperature difference between the inside of the enclosure and the outside of at least 10°C (Ti > Te).

Thermoelectric cabinet coolers are the ideal solution to cool and remove heat from small cabinets, control panels and consoles. Its technology and design make them especially suitable for harsh environments like food industry or traffic engineering.  The cabinet coolers utilize solid state peltier technology and can be operated in any orientation. Separation of internal air circulation and ambient external air flow and a hermetical seal at the flange guarantee protection class IP65.

Cooling capacities range from 30 to 280 W (nominal, internal equals external temperature) respectively 190 to 610 W (20 K above ambient, equivalent to 9 to 30 W/K heat removal).

>>Peltier effect

The Thermoelectric Cooler uses the Peltier effect for cooling. This effect is based on the principle that an electric direct-current flowing through a circuit consisting of two different metals causes the cooling of one contact point and the heating of the other contact points. An appropriate layout for the cooling production is designated as Peltier element.

When the Peltier effect is used for enclosure climate control, an air flow is fed over the upper and lower connection point. The heat energy is released or accepted from the air flow to the Peltier element. The air flow that releases the heat energy to the element is introduced as cooling air flow in the enclosure or the operating housing.

After the heating of the cooling air flow by the active installed equipemt, it is returned to the cooling unit and fed for renewed cooling over the “cold” side of the Peltier element. This produces an air circulation that causes the cooling of the enclosure or the operating housing. The air flow that accepts the heat energy from the “warm” side of the Peltier element is released as warm air flow to the external air circuit of the cooling unit. This means the heat produced by the components in the enclosure is dissipated to the ambient air surrounding the cooling unit.