Non-equilibrium thermal fluctuations of flow in thermal systems

Fouling is detrimental to the heat transfer performance of concentrated solar power (CSP) plant components where heat exchange takes place with the cooling tower water. Wave elements cause an expression of deep insight of the fouling formation. A wave element is the wave interface between two molecule groups with different temperatures in flow; it is generated by density difference, which results from temperature difference. Tiny temperature differences always exist everywhere in a fluid. When a fluid is in motion, wave elements are generated among molecule groups. Wave motion and Brownian motion can be the two basic forms of motion of the molecules in flow. Temperature controls Brownian motion. Temperature differences and the fluid's motion cause the wave elements. Non-equilibrium thermal fluctuations present as wave elements in a flow. A wave element appears as wave behavior along the space and time dimensions that are based on the continuity relation. The direct experimental evidence for wave elements cannot be directly established at the present scientific testing capability because the temperature difference of two molecule groups adjoining each other in a flow is infinitesimal. A series of “enlarged size” experiments are conducted involving the cooling tower water fouling to show the wave elements' behaviors by tracing the molecules' movement. The experimental study presents that the wave interface along the space and time dimensions simultaneously exists between two densities due to fluid motion. The experimental evidence and theoretical analysis support each other.

Design of Wave Glider Optimal Parameters Suitable for the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea

To study the optimal design of Wave Glider parameters in the wave environment of the Northwest Pacific Ocean, the North Indian Ocean, and the South China Sea, the average velocity of a Wave Glider was taken as the evaluation criterion. Wave reanalysis data from ERA5 were used to classify the mean wave height and period into five types by the K-means clustering method. In addition, a dynamic model was used to simulate the influence of umbilical length, airfoil, and maximum limited angle on the velocity of the Wave Glider under the five types of wave element. The force of the wings was simulated using FLUENT as the model input. The simulation results show that (1) 7 m is the most suitable umbilical length; (2) a smaller relative thickness should be selected in perfect conditions; and (3) for the first type of wave element, 15° is the best choice for the maximum limited angle, and 20° is preferred for the second, third, and fourth types, while 25° is preferred for the fifth type.

Non-Equilibrium Thermal Fluctuation in Flow

Non-equilibrium thermal fluctuations present as wave elements in a flow. A wave element is the wave interface between two molecule groups with different temperature; it is generated by density difference which results from temperature difference. Tiny temperature differences always exist everywhere in a fluid. When the fluid is in motion, wave elements are generated among molecule groups. Wave motion and Brownian motion may be the two basic forms of motion of molecules in flow. Brownian motion is controlled by temperature. Wave elements are caused by temperature differences and the motion of the fluid. Wave motion maybe the physical mechanism of convective heat transfer. Non-equilibrium thermal fluctuations exist everywhere among molecule groups in a flow. The theoretical analysis presents that a wave element presents oscillatory behavior along the space and time dimensions simultaneously. The experimental evidence for wave elements can not be directly established at present scientific testing capability because the temperature difference of two molecule groups adjoining to each other in a flow is very small. A series of “enlarged size” experiments of fouling to show the behaviors of wave elements by tracing the movement of molecules are conducted. The experimental study of fouling presents that oscillatory interface along the space and time dimensions simultaneously exists between two densities due to motion of the fluids. The experimental and theoretical analyses are supported to each other.

A spectral model for signal elements isolated from zebrafish photopic electroretinogram

The zebrafish photopic electroretinogram (ERG) sums isolatable elements. In each element, red-, blue-, green-, and UV- (r, g, b, and u) cone signals combine in a way that reflects retinal organization. ERG responses to monochromatic stimuli of different wavelengths and irradiances were recorded on a white rod suppressing background using superfused eyecups. Onset elements were isolated with glutamatergic blockers and response subtractions. CNQX-blocked ionotropic (AMPA/kainate) glutamate receptors; l-AP4 or CPPG-blocked metabotropic (mGluR6) glutamate receptors; TBOA-blocked glutamate transporters; and l-aspartate inactivated all glutamatergic mechanisms. Seven elements emerged: photopic PIII, the l-aspartate-isolated cone response; b1, a CNQX-sensitive early b-wave element of inner retinal origin; PII, a photopic, CNQX-insensitive composite b-wave element from ON bipolar cells; PIIm, an l-AP4/CPPG-sensitive, CNQX-insensitive, metabotropic subelement of PII; PIInm, an l-AP4/CPPG/CNQX-insensitive nonmetabotropic subelement of PII; a1nm, a TBOA-sensitive, CNQX/l-AP4/CPPG-insensitive, nonmetabotropic, postphotoreceptor a-wave element; and a2, a CNQX-sensitive a-wave element linked to OFF bipolar cells. The first five elements were fit with a spectral model that demonstrates independence of cone–color pathways. From this, Vmax and half-saturation values (k) for the contributing r-, g-, b-, and u-cone signals were calculated. Two signal patterns emerged. For PIII or PIInm, the Vmax order was Vr > Vg >> Vb ≈ Vu. For b1, PII, and PIIm, the Vmax order was Vr ≈ Vb > Vg > Vu. In either pattern, u-cone amplitude (Vu) was smallest, but u-cone sensitivity (ku362) was greatest, some 10–30 times greater than r cone (kr570). The spectra of b1/PII/PIIm elements peaked near b- and u-cone absorbance maxima regardless of criteria, but the spectra of PIII/PIInm elements shifted from b- toward r-cone absorbance maxima as criterion levels increased. The greatest gains in Vmax relative to PIII occurred for the b- and u-cone signals in the b1/PII/PIIm b-wave elements. This suggests a high-gain prolific metabotropic circuitry for b- and u-cone bipolar cells.