The forced convection experiment of fan plate-finned tube heat exchangers which are mainly used in air conditioners and the forced convection model have been studied for which the heat transfer effect of this type exchangers has not been proposed by a model. All measurements were made when there is no refrigerant flow in the pipe at Reynolds's number of 580. According to the experiment results,...

This paper demonstrates the use of poly(dimethylsiloxane) (PDMS), polyurethane (PU), epoxy, and poly(methyl methacrylate) (PMMA) as mandrils to fabricate metallic heat exchangers having 300–700 m internal channels. The mandrils were prepared using two soft lithographic techniques-replica molding, and microembossing. To fabricate the heat exchangers, the polymeric mandrils were coated with a thi...

Vascular structures for heat conservation in the tongue of the gray whale (Eschrichtius robustus) are reported here. Numerous individual countercurrent heat exchangers are found throughout the massive tongue. These converge at the base of the tongue to form a bilateral pair of retia. Temperature measurements from the oral cavity of a live gray whale indicate that more heat may be lost through t...

This paper presents how the thermal performance of an existing finned-tube heat exchanger is determined experimentally. In the experiment, heat is transferred from an exhaust gas stream to a thermal oil. The experimental setup is discussed including the thermal fluid selection process, the components, instrumentation and resultant measurement uncertainty. The heat transfer is calculated individ...

Micro-scale silicon heat exchangers were designed, modeled using conventional heat transfer and fluid mechanics correlations, fabricated in the MIT Microtechnologies Laboratory, and tested as part of the MIT micro-gas turbine engine project. Heat transfer and pressure drop experiments were carried out to measure the performance of these heat exchangers, and to validate the predictions of the mo...

The thermal performance of a heat exchanger is important for the potential application in an integrated solar cell/module and thermoelectric generator (TEG) system. Usually, the thermal performance of a heat exchanger for TEGs is analysed by using 1D heat conduction theory which ignores the detailed phenomena associated with thermo-hydraulics. In this paper, thermal and momentum transports in t...

In the present study, the heat transfer coefficients of benzene in a spiral plate heat exchanger are investigated. The test section consists of a Plate of width 0.3150 m, thickness 0.001 m and Mean hydraulic diameter of 0.01 m. The mass flow rate of water (Hot fluid) is varying from 0.5 kg sec to 0.8 kg sec and the mass flow rate of benzene (cold fluid) varies from 0.4 kg sec to 0.7 kg sec. Exp...

Plate fin-tube heat exchangers are used extensively in heating, ventilating, and air conditioning, process engineering, and refrigeration systems. They have a high degree of surface compactness. Substantial heat transfer enhancement is obtained as a result of the periodic starting and development of boundary layers over interrupted channels formed by the fins and their dissipation in the fin wa...

Title of Document: DEVELOPMENT OF AN ADVANCED HEAT EXCHANGER MODEL FOR STEADY STATE AND FROSTING CONDITIONS Varun Singh Doctor of Philosophy, 2009 Directed By: Reinhard Radermacher, Professor Department of Mechanical Engineering Air-to-refrigerant fin-and-tube heat exchangers are a key component in the heating, air conditioning and refrigeration industry. Considering their dominance, the indust...