Flat plate heat pipe

Rightley M.J., Tigges C.P., Civler R.C., Robino C.V, Mulhall J.J., Smith P.M., (2003), Innovative wick design for multi - source, flat plate heat pipes. Microelectronic Journal,... 

The second example that has implications for reactions, but is more commonly associated with electronics thermal control, is the flat plate heat pipe. Two variants are shown in Figures 11.23 and 11.24. It is often used for heat spreading or temperature flattening and is highly effective in this role. The applications of the flat plate unit inclnde, but are not limited to ... 

The heat exchanger can be a pipe system as shown in Figure 149 or with flat plate heat exchangers as in Figure 127. 

Whitaker, S., Forced Convection Heat-Transfer Correlations for Flow in Pipes, Past Flat Plated, Single Cylinders, Single Spheres, and Flow in Packed Beds and Tube Bundles , AIChE J.. Vol. 18, pp. 361-371.1972. 

Whitaker, S. Forced convection heat transfer correlations 26. for flow in pipes, past flat plates, single cylinders, single spheres, and for flow in packed beds and tube bundles. 27. AIChE J. 1972, 18, 361-371. 

You saw how the equations governing energy transfer, mass transfer, and fluid flow were similar, and examples were given for one-drmensional problems. Examples included heat conduction, both steady and transient, reaction and diffusion in a catalyst pellet, flow in pipes and between flat plates of Newtonian or non-Newtonian fluids. The last two examples illustrated an adsorption column, in one case with a linear isotherm and slow mass transfer and in the other case with a nonlinear isotherm and fast mass transfer. Specific techniques you demonstrated included parametric solutions when the solution was desired for several values of one parameter, and the use of artificial diffusion to smooth time-dependent solutions which had steep fronts and large gradients. 

The analogy between heat and momentum does not account for the pressure drop in pipes and is not, strictly speaking, valid for pipe flow. However, the effect of pressure drop on this analogy appears to remain within the uncertainty of the available experimental data and is usually ignored. Next, introducing Eq. (6.16) into Eq. (5.63) gives the heat transfer in fully developed turbulent flow over a flat plate,... 

MORE ACCURATE ANALOGY EQUATIONS. A number of more elaborate analogy equations connecting friction and heat transfer in pipes, along flat plates, and in annular spaces have been published. They cover wider ranges of Reynolds and Prandtl numbers than Eq. (12.52) and are of the general form... 

Equation (7.3-13) has been shown to be quite useful in correlating momentum, heat, and mass transfer data. It permits the prediction of an unknown transfer coefficient when one of the other coefficients is known. In momentum transfer the friction factor is obtained for the total drag or friction loss, which includes form drag or momentum losses due to blunt objects and also skin friction. For flow past a flat plate or in a pipe where no form drag is present, //2 = J = Jp- When form drag is present, such as in flow in packed beds or past other blunt objects,772 is greater thanJ, otJ andJ s Jg. 

Figure I 1.23 Embedded heat pipes in a flat plate (courtesy Thermacore Ltd).

The heat pipe vapour chamber is a completely hollow flat plate in which evaporation, and condensation of the working fluid in it, can take place. Again it can be used to isothermalise a surface on which a variable heat distribution is occurring. The variable heat input/output could be a catalysed reaction surface. 

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