Flow and Cold Heat-Storage Characteristics of Phase-Change Emulsion in a Coiled Double-Tube Heat Exchanger

Abstract

This paper dealt with the flow and cold heat-storage characteristics of the oil (tetradecane, C14H30, freezing point 278.9 K)/water emulsion as a latent heat-storage material having a low melting point. A coiled double-tube heat exchanger was used for the cold heat-storage experiment. The pressure drop, the heat transfer coefficient, and the finishing time of cold heat storage in the coiled tube were measured as experimental parameters. It was understood that the flow behavior of the emulsion as a non-New-tonian fluid had an important role in the present cold heat storage. The useful nondi-mensional correlation equations for the additional pressure loss coefficient, the heat transfer coefficient, and the cold heat storage time were derived in terms of modified Dean number and heat capacity ratio.

A continuum model for transport phenomena in convective flow of solid–liquid phase change material suspensions

“…(35) represents the liquid phase fraction flux due to relative motion. Taken together, the equations of (6), (12), (17), (28) and (35) constitute the mixture continuum formulation describing the heat and mass transport phenomena of convective flow of PCM suspensions, which can be implemented and solved numerically for specific PCM suspension flow with proper specification of the mixture properties on an Eulerian grid. If the effects of the Brownian diffusion and the relative motion of the suspension particles on the transport processes of momentum, heat and mass can be simultaneously ignored, the PCM suspension flow can be treated as that of a homogeneous mixture with particle mass fraction / p .…”

“…In contrast to conventional particulate suspensions [2], the PCM suspension can serve as a dual-functional medium for energy transport and/or storage. Effect of PCM particles in suspensions on forced convection heat transfer in duct flows has been the subject of many investigations, concentrating on applications of heat transfer enhancement [3][4][5][6][7][8][9][10][11] and energy storage [12,13] respectively.…”

Formation of tetradecane nanoemulsion by low-energy emulsification methods

“…The melting point of tetradecane has been reported to range between 5.1 and 6 C (Inaba and Morita, 1995;Inaba and Morita, 1996;Bo et al, 1998;Dumas, 2005;Gschwander et al, 2005;Xu et al, 2005;Oxford, 2007;Fang et al, 2009) and even 6.7 C (Yang et al, 2003). When a tetradecane sample freezes, a supercooling effect has been observed in Differential Scanning Calorimetry (DSC) measurements in the past.…”

“…Some literature results are shown in Table 3 where emulsion to water viscosity ratios are given for better comparison since experiment temperatures were not the same e for the sake of analysis, Inaba and Morita's (1995) results are estimated based on their pressure drop measurements. Most results are consistent with the theory (Becher, 1955;Ramirez et al, 2002): the viscosity decreases with droplet size.…”

The Thermal Performance of a Novel Phase Change Emulsion

“…Inaba et al (1995Inaba et al ( , 1996 have prepared a PCE with tetradecane (C 14 H 30 ) (Tm D 5.9 ı C, Hm D 229 KJ/kg) as phase change material (PCM) and studied the air-emulsion direct contact heat exchange. A PCE has been prepared with micro-particles of tetradecane and water by using a phase incursion method (PIM), and some of the thermal physical properties of the PCE were measured.…”