Subcooling

About: Subcooling is a research topic. Over the lifetime, 6150 publications have been published within this topic receiving 99125 citations.

Freezer-refrigerator and cooling storage unit

Abstract: A freezer-refrigerator comprising: a refrigeration compartment (2) for refrigerating and storing an object to be stored; a freezing compartment (4) for freezing and storing an object to be stored; a first compressor (11) for operating a first refrigeration cycle (10) in which a first refrigerant flows; a first heat dissipater (12) provided to a high-temperature section of the first refrigeration cycle (10); a first evaporator (14) provided to a low-temperature section of the first refrigeration cycle (10); a second compressor (21) for operating a second refrigeration cycle (20) in which a second refrigerant flows; a second evaporator (24) provided to a low-temperature section of the second refrigeration cycle (20); and an intermediate heat exchanger (31) for performing heat exchange between the low-temperature section of the first refrigeration cycle (10) and a high-temperature section of the second refrigeration cycle (20). The first evaporator (14) cools the refrigeration compartment (2), and the second evaporator (24) cools the freezing compartment (4).

Experiments on the effects of nanoparticles on subcooled nucleate pool boiling

Abstract: The effect of nanoparticles on a single bubble-based nucleate pool boiling phenomenon under subcooled conditions has been studied. Water (as the base fluid) and two different concentrations of water-silica nanofluids (0.005% and 0.01% V/V) have been employed as the working fluids. The boiling experiments have been conducted in a specially designed chamber, wherein an ITO-coated heater substrate has been used to induce single bubble nucleation. Measurements have been performed in a completely non-intrusive manner using one of the refractive index-based diagnostics techniques, namely, rainbow schlieren deflectometry. Thus, the thermal gradients prevailing in the boiling chamber have directly been mapped as a two-dimensional distribution of hue values that are recorded in the form of rainbow schlieren images. The schlieren-based measurements clearly revealed the plausible influence of nanoparticles on the strength of temperature gradients prevailing in the boiling chamber. As compared to the base fluid, the experiments with dilute nanofluids showed that the suspended nanoparticles tend to diffuse (homogenize) the strength of temperature gradients, both in the vicinity of the heated substrate and in the thermal boundary layer enveloping the vapor bubble. An overall reduction in the bubble volume and dynamic contact angle was seen with increasing concentrations of dilute nanofluids. In addition, the vapor bubble was found to assume a more spherical shape at higher concentrations of dilute nanofluids in comparison to its shape with water-based experiments. Clear oscillations of the vapor bubble in the subcooled pool of liquids (water and/or nanofluids) were observed, the frequency of which was found to be significantly reduced as the nanoparticle concentration was increased from 0% (water) to 0.01% (V/V). A force balance analysis has been performed to elucidate the plausible mechanisms explaining the observed trends of the oscillation frequencies of the vapor bubble.

Role of the surface in the measurement of the Leidenfrost temperature

Abstract: Surface roughness and contamination, drop volume and liquid subcooling effects on Leidenfrost temperature