Two-phase flow has been frequently used in industry since long time ago. In most of the processing industries, the flow is biphasic, which is the simultaneous flow of two different fluids through a conduit. Two-phase flow is the method of choice in the majority of the manufacturing processes and different fluid pairs like water-air, oil-water and carbon particles-vapor are simultaneously used in this regard. Gas and liquid phases are the common components of such flows. Accordingly, the optimum use of energy and elevation of the processes’ output are the most important issues considered in the majority of the world’s industrial processes. In between, direct contact thermal exchangers are being widely applied in processing industries and have many benefits in respect to indirect contact thermal exchangers.