This paper deals with the hydrodynamic and thermal analysis of a new type of porous heat exchanger (PHE). This system operates based on energy conversion between gas enthalpy and thermal radiation. The proposed PHE has one high temperature (HT) and two heat recovery (HR1 and HR2) sections. In HT section, the enthalpy of flowing high temperature gas flow that is converted to thermal radiation em...

A new class of helium-cooled high heat-flux plasma facing heat exchanger (HX) concept is presented. These unique “Foam-In-Tube” HX concepts are composed of a thin tungsten shell integrally bonded to an open-cell tungsten foam core. High heat flux tests show maximum heat loads of 22.4 MW/m using 4 MPa helium at a flow rate of 27 g/s. Based on these impressive performance results, a unique and sc...

The forced convection heat transfer in high porosity metal-foam filled tube heat exchangers are studied in this paper. The Brinkman Darcy momentum model and two energy equations for both solid and fluid phases in porous media are employed .The study shows that using metal-foams can significantly improve the heat transfer in heat exchangers. Keywords—metal foam, Nusselt number, heat exchanger, h...

Polymerase chain reaction (PCR) is widely used in biochemical analysis to amplify DNA and RNA in vitro. The PCR process is highly temperature sensitive, and thermal management has an important role in PCR operation in reaching the required temperature set points at each step of the process. The goal of this research is to achieve a thermal technique to rapidly increase the heating/cooling therm...

abstract: in this study, al 2 o 3 /eg and tio 2 /eg nanofluids as coolants have been used in the double-tube heat exchanger. the hot solvent inlet heat exchanger must be cooled down with a specified amount. we can use nanofluids as coolants in the heat exchanger for optimization of the heat transfer area. therefore, the efficacy of nanofluids as coolants is verified. furthermore, flow rate of c...

The focus of this work is the modeling and performance comparison of different models of pulse tube refrigerators, namely, the Orifice Pulse Tube Refrigerator (OPTR) and the Inertancetube Pulse Tube Refrigerator (IPTR) with both in-line as well as coaxial configurations. A detailed analysis of the flow and heat transfer in various components of the above mentioned models under oscillating flow ...

heat exchangers are the critical components of refrigeration and liquefaction processes. selection of appropriate operational conditions for cryogenic recuperative heat exchanger and expansion valve operating in joule-thomson cooling system results in improving the performance and efficiency. in the current study, a straightforward procedure is introduced to design an efficient joule-thomson co...

in the presented research, heat transfer of a mobile electrolyte alkaline fuel cell (afc) (which the electrolyte has cooling role of system) has been considered. proper control volumes of system with specific qualification have been chosen. consequently, heat and mass transfer in control volumes have been assessed. considerations on them and contributed models lead to approve a double tube heat...

1 Fellow, ASME Abstract A semi-empirical model for conduction/convection in a thin “fin-like” porous wall of arbitrary composition and thickness is developed. The model assumes one-dimensional conduction in the porous matrix and one-dimensional flow of the coolant through the wall. Closed form solutions are obtained for a uniform composition and thickness porous wall having an insulated tip. An...

Experimental investigations has been done to find out the heat transfer characteristics and friction factor of water based Al2O3 nanofluids as a coolant in  brazed plate heat exchanger. Plate heat exchanger either use horizontally or vertically. The base plate of the plate heat exchanger was kept inclined at (0⁰, 30⁰ ,60⁰, 90⁰). The experimentation have been done on the two different concentrat...