Thermocapillary pumping

The thermal effect is exploited to produce liquid pumping. For instance, a thermocapillary pump was constructed. The pumping method is based on surface-tension change due to local heating created by heaters fabricated on a Si-Pyrex chip. This method was used to pump reagents to perform successive PCR, gel electrophoresis, and detection [392,393],... 

Sammarco, T.S. Burns, M.A. Thermocapillary pumping of discrete drops in microfabricated analysis devices. AIChE J. 1999, 45 (2), 350-366. 

Thermocapillary pumping (TCP) is a pumping concept based on thermocapillary forces, where a liquid droplet moves through a microchannel or on a planar surface. A temperature gradient leads to a difference of the surface stresses across a liquid droplet and propels it into a cooler region. 

Thermocapillary Pumping, Fig. 1 Experimental setup for measuring the receding (a) and advancing (b) contact angle in a microchannel... 

Glockner and Naterer reported a new method of cyclic flow control with an external heat source is developed for thermocapillary pumping of a microdroplet in a closed microcharmel [12]. The pumping concept involves a stationary cyclic heat source embedded within an adjoining... 

Thermocapillary Pumping, Fig. 2 Section of a bubble in a horizontal tube. Five regions are shown the constant film thickness region (1), two capillary static s regions (3, 5), and two transition regions (2,4)... 

Thermocapillary Pumping, Fig. 3 Splitting of a droplet using thermocapillary force. When the heater is turned on, the induced temperature gradient causes the droplet to move away from the heater. As a result, the droplet is split at its center... 

Despite its simplicity in implementation, thermocapillary pumping was not fully exploited in microfluidics research community. Thermocapillary may have a big impact in droplet-based digital micro fluidics. Besides droplet transport, thermocapillary force can be used... 

DeBar MJ, Liepmann D (2002) Fabrication and performance testing of a steady thermocapillary pump with no moving parts. In Proceedings of the IEEE micro electro mechanical systems (MEMS 2002). Las Vegas, USA, pp 109-112... 

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