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This investigation deals with numerical treatment of heat transfer flow of a third grade fluid between two infinite parallel plates subject to no-slip condition at boundary and no-temperature jump. Three flow configurations, Couette, Poiseuille, and plane Couette-Poiseuille, have been discussed. Approximate solutions using Lagrange-Galerkin method to Couette, Poiseuille, and Couette-Poiseuille flow problems are computed and delineated. It has been substantiated that the fluid rheology and heat transfer phenomenon are greatly influenced by the third grade flow parameters, Brinkman number, and pressure gradient. A rigorous mathematical exposition of the numerical scheme is provided. Because no a priori assumptions are made on pertinent flow parameters, apart from those due to thermodynamic stability, the results presented in this investigation are also valid for their large values. [ABSTRACT FROM AUTHOR]

Ice slurry displays many advantages as a phase-change material because the latent heat of ice particles can be used and their heat exchange area is large. In this study, the effect of initial concentration on the rheological behavior of ice slurry was investigated experimentally. Ice slurry flowed upward and downward to keep it homogeneous in the tube, and pressure drop was measured to explain the rheological behavior of the ice slurry. The ice packing factor, Reynolds number, and initial aqueous solution concentration were varied as parameters. The ice slurry flow characteristics exhibit a pseudo-plastic fluid tendency for 5 and 10 wt% of the initial concentration. Ice slurry generated from 2 wt% ethanol solution behaves as a Newtonian fluid. [ABSTRACT FROM AUTHOR]

Abstract: Thermal or cold storage by phase change material slurry attracted many attentions in recent years, in which solid fraction distribution in the storage tank is an important issue due to different densities of the solid particle and carrier fluid. Tetra-n-butyl ammonium bromide (TBAB) clathrate hydrate slurry (CHS) has recently been intensively investigated for the purpose of the cold storage. In the present study, solid fraction distribution of TBAB CHS in a cold storage tank was both experimentally and numerically investigated. The different sedimentation characteristics of type A and type B TBAB CHS were identified. It was shown that high-capacity cold storage can be achieved by taking advantage of the sedimentation of type A TBAB CHS, based on which a procedure to realize it was also proposed. [Copyright &y& Elsevier]

Abstract: The flow and heat transfer characteristics of ice slurry were investigated experimentally. The characteristics in the transition region were examined in detail. The ice slurry was produced from ethanol solution. Ice packing factor (IPF), Reynolds number and tube diameter were varied as experimental parameters, and the coefficients of pipe friction and heat transfer were measured. In the low IPF region, the coefficients of the pipe friction and heat transfer were found to be constant with values that were the same as for turbulent flow in an ethanol solution. However, for the high IPF region, laminarization occurs and flow and heat transfer characteristics can be estimated from the laminar flow of the ice slurry. Moreover, the laminarization point can be estimated using the apparent Reynolds number. [Copyright &y& Elsevier]

Abstract: Flow and heat transfer characteristics of ammonium alum hydrate slurries have been investigated. Ammonium alum hydrate has high latent heat of 251 kJ kg−1 and its melting temperature is 51 °C when the concentration of ammonium alum in water was set at 35 wt%. The friction and the melting heat transfer coefficients were measured in a pipe flow with 13 mm of diameter. From the results, it was found that the friction coefficient of ammonium alum hydrate slurry shows almost the same value as that of water. On the other hand, the slurry shows higher heat transfer than that of water. Especially, the heat transfer enhanced rate becomes high when the temperature difference between the slurry and the heating flow was set small. This is because of the temperature sustainability of phase change material slurries. From this, it was concluded that ammonium alum hydrate slurry can be a promising candidate for a heating system. [Copyright &y& Elsevier]

Abstract: The flow and heat transfer characteristics of a tetra-n-butyl ammonium bromide (TBAB) hydrate slurry were investigated experimentally. The characteristics in the transition region were examined in detail. Two types of hydrates form from TBAB solution of different concentrations. The hydrate type, Reynolds number and solid fraction were varied as experimental parameters and the coefficients of pipe friction and heat transfer were measured. In the low solid fraction region, it was found that the coefficients of pipe friction and heat transfer were constant and the values were the same as that for turbulent flow of the TBAB solution. However, for the high solid fraction region, a laminarization phenomenon occurs and the flow and heat transfer characteristics can be estimated from the laminar flow of the hydrate slurry. Moreover, the laminarization point for the solid fraction can be predicted using the apparent Reynolds number. [Copyright &y& Elsevier]

Abstract: The paper presents the results of experimental research on up to 15% ice slurry made from 10.6% ethylene alcohol. It looks at the pressure loss coefficient during its laminar flow through sudden contractions and expansions. The experimental investigations dealing with pressure loss coefficients were preceded by considerations and calculations in the field of the rheological behaviour of the ice slurry. Similarly to what can be found in papers by some other authors, two different types of behaviour were observed, depending on the shear rate values: behaviour close to the Bingham model for the low shear rate region, and for high shear rate values, a power law with a shear thickening behaviour. To predict ice slurry behaviour in both the low and the high shear rate region, the modified Herschel–Bulkley rheological model was suggested. In this model, generalized correlations for the yield stress, the consistency coefficient and the flow index were proposed. [Copyright &y& Elsevier]

Abstract: In this study, we investigated the pressure drops and loss coefficients of a phase change material slurry-tetrabutylammonium bromide (TBAB) clathrate hydrate slurry (CHS) in pipe fittings. Pressure drops of TBAB CHS in 6mm and 14mm straight tubes, 14mm 90° elbow, sudden contraction from 14mm to 6mm, sudden expansion from 6mm to 14mm, 14mm tee distribution and convergence were measured as the mass fraction of TBAB CHS varying from 0wt% to 30wt%. Power-law model was applied to describe the characteristics of slurry flow, and the fluid parameters including the flow behavior index and fluid consistence factor were obtained for 6mm and 14mm tubes respectively. Furthermore, the loss coefficients of TBAB CHS flowing through the pipe fittings were obtained from the experimental results and the corresponding correlations were also developed. [Copyright &y& Elsevier]

Abstract: The heat transfer characteristics of a tetra-n-butyl ammonium bromide hydrate slurry were investigated where the Reynolds number, tube diameters and solid fraction were varied as experimental parameters. For laminar flow, it was found that the ratio of Nusselt numbers increased with solid fraction. An approximation of Nusselt number could be derived using the Graetz number on the basis of the apparent Reynolds number, the solid fraction and the ratio of the average diameter of the hydrate particles to the test tube diameter. For turbulent flow conditions, the ratio of Nusselt numbers had a value of one for each condition at low solid fractions. The ratio of Nusselt numbers increased with solid fraction in the high solid fraction region. Moreover, the apparent Reynolds number, which can be derived by treating the hydrate slurry as a pseudoplastic fluid, can be used to determine the condition under which hydrate slurry heat transfer characteristics vary under turbulent flow. [Copyright &y& Elsevier]

Abstract: The flow characteristics of a tetra-n-butyl ammonium bromide hydrate slurry were investigated experimentally. Reynolds number, tube diameter and solid fraction were varied as the experimental parameters. For laminar flow, it was found that the ratio of the coefficients of pipe friction increases with solid fraction, and the rate of increase is high in the case of a low Reynolds number. For turbulent flow, the ratio of the coefficients of pipe friction was approximately 1 for all tube diameters at low solids fraction. It then decreased slightly at a particular solid fraction and increased again at high solid fraction. Theoretical analysis was carried out using the experimental results, and it was found that the flow characteristics of the hydrate slurry can be treated as those of a pseudoplastic fluid and clarified using the apparent Reynolds number. [Copyright &y& Elsevier]

We correct certain errors and ambiguities in the recent pedagogical article by Hopkins and de Bruyn ( Can. J. Phys. 92, 533 (2014). ). The early-time asymptotics of the solution to the transient version of Stokes' second problem for an Oldroyd-B fluid in a half-space is presented, as Appendix A, to complement the late-time asymptotics given by Hopkins and de Bruyn. [ABSTRACT FROM AUTHOR]