Quenching of small stainless steel rods in pure water and nanofluids with alumina and diamond nanoparticles at low concentrations (0.1 vol%) was investigated experimentally. The rods were heated to an initial temperature of ~1000 C and then plunged into the test fluid. The results show that the quenching behavior of the nanofluids is nearly identical to that of pure water. However, due to nano...

Pool boiling heat transfer has been extensively studied over decades, but the effect of boundary heating conditions on boiling received little attention. In this work, heat transfer coefficients during pool boiling of five different refrigerants (R123, R245fa, R236fa, R134a, and R22) on the outside surface of a smooth copper tube were measured at the saturation temperature of 6.7 C; water flows...

The additive model for the convective and nucleate boiling components originally suggested by Bergles and Rohsenow (1964) for subcooled and low-quality regions was employed in the Kandlikar correlation (1990a) for flow boiling in smooth tubes. It is now extended to augmented tubes and compact evaporators. Two separate factors are introduced in the convective boiling and the nucleate boiling ter...

Boiling--a process that has powered industries since the steam age--is governed by bubble formation. State-of-the-art boiling surfaces often increase bubble nucleation via roughness and/or wettability modification to increase performance. However, without active in situ control of bubbles, temperature or steam generation cannot be adjusted for a given heat input. Here we report the ability to t...

Chilldown or quenching is a complicated process that initiates the cryogenic fluid line transport, and it involves unsteady two-phase heat and mass transfer. To advance our understanding of this process, we have reviewed recent experimental investigations. The chilldown process can be generally divided into three regimes: film boiling, transition boiling and nucleate boiling, and each regime is...

With the long-term objective of Critical Heat Flux (CHF) prediction, a Direct Numerical Simulation (DNS) framework for simulation of subcooled and saturated nucleate pool boiling is developed. One case of saturated, and three cases of subcooled boiling at different subcooling levels are simulated. Grid refinement study is also reported. Both boiling and condensation phenomena can be computed si...

A three-dimensional two-fluid code NEPTUNE_CFD has been validated against the ASU (Arizona State University) [1] and DEBORA [2, 3] boiling flow experiments. Nucleate boiling processes in the subcooled flow boiling regime have been studied on ASU experiments. Within this scope a new wall function is implemented in the NEPTUNE_CFD V1.0.6 code to improve the prediction of flow parameters in the bo...

background: antibiotic residue in food is a major concern from a health point of view. post-slaughter and pre-consumption processing such as cooking could affect residue. objectives: the purpose of this study is to survey the effect of boiling and microwave on tilmicosin in chicken. methods: chicken samples containing different tilmicosin amounts cooked in boiling water and in the microwave. af...

In this paper, an attempt has been made to estimate the convective heat and mass transfer for pool boiling of sugarcane juice during preparation of jaggery. An indoor experiment was conducted to measure (i) the mass of evaporated water, (ii) the temperature of the sugarcane juice, (iii) the relative humidity above the sugarcane juice surface and (iv) the temperatures at the bottom and side of t...