ABSTRACT
Plate heat exchangers are a success story in heat transfer application, as they have replaced shell-and-tube heat exchangers in many industrial plants within the last 15 years. This is due to the very high thermal performance of these devices. Unfortunately no reliable correlation is known to calculate local nor overall heat transfer coefficients for arbitrarily corrugated plates. Thus extensive measurements have to be performed for each type of plate to enable thermal design of plate heat exchangers. Knowledge about precise local heat transfer coefficients is preferable, because this knowledge would allow for learning about the influence of corrugation pattern on heat transfer performance.
The presentation reports on an experimental method to extract local heat transfer coefficients from plates under operating conditions. The method used is the Temperature Oscillation Infrared Thermography (TOIRT-method), were an oscillating heat flux is applied to a heat transfer surface and the temperature response is measured with an Infrared Camera. The heat transfer which is to be measured is on the back side of the plate, so the flow is not obstructed.
