Potential mapping of ground source heat pump systems considering groundwater pumping

The pumping of groundwater near GHEs improves the performance of GSHP systems due to the advection of the induced roundwater flow when the hydraulic conductivity of the formation is favorable. To quantify the effect, we first carried out performance analysis of a GSHP heating system under the influence of groundwater pumping. The heating operation data clearly showed the improved COP of the heat pump when the groundwater is pumped. To evaluate the effect of groundwater pumping, we then collected the water pumping data from the groundwater snow-melting system in Akita City, Japan and input those data to the existing field-scale numerical groundwater flow and heat transport model of the area. The model was run to calculate the groundwater velocity and temperature in the area under the influence of groundwater pumping. Then, the output from the model was used for developing another numerical model, small-scale GHE model, which can estimate the minimum necessary GHE length for a Japanese standard detached house at several locations in the area. The GHE length data were mapped using GIS software to generate the GSHP potential map under the influence of groundwater pumping. The comparison between the potential maps with and without groundwater pumping clearly indicated the contribution of water pumping in reducing the GHE length and the initial cost of GSHP systems

Field tests and numerical simulation of a novel thermal response test equipment for water wells

The objective of this study is to develop a novel thermal response test (TRT) equipment that can be applied to existing water wells instead of borehole heat exchangers (BHEs). Accordingly, field tests were conducted using new and conventional equipment to estimate the vertical distribution of ground thermal conductivity. The result showed that the estimated thermal conductivity profile was higher than the reference profile obtained using conventional equipment. The temperature behavior in the well was considered to be unstable due to natural convection because the heating time was 4 hours, which is not long enough. Next, a numerical model of the water well including the novel equipment was developed, and the model was validated through history matching by using the temperature change in each depth. Finally, the TRT was simulated for two days using the model, and the simulated thermal conductivity profile was similar to the reference profile except near the end of the heated section. This result indicates that a more accurate thermal conductivity profile can be obtained by increasing the heating time until approximately 1.5 days

Friction of 316L stainless steel on soft-tissue-like poly(vinyl alcohol) hydrogel in physiological liquid

International audienc

Friction of 316L stainless steel on soft-tissue-like poly(vinyl alcohol) hydrogel in physiological liquid

International audienc

Thermal change of culture medium on a heating plate during TRTS.

<p>(A, B) One day before a thermal evaluation, the cell-free growth medium was transferred into a 24-well culture plate. The plate was set on a heating plate in a CO₂ incubator and incubated for 24 h with a temperature sensor for monitoring medium temperature. (A) The temperatures of the medium during TRTS exposure (for total 18 h) that were recorded every 60 sec are shown. The data represent the mean of three replicates. (B) The average medium temperatures during heating stimulation for 18 h are shown. The data represent the mean ± SD of three replicates. **<i>P</i> < 0.01 vs. no-TRTS controls. Pre-set temperature of the heating plate to warm culture medium was 39.5°C or 42°C. There was a 1-h break between the 3-h thermal stimulations. TRTS, temperature-controlled repeated thermal stimulation.</p

TRTS-induced changes in PC12 cell differentiation after exposure to various inhibitors.

<p>(A–K) PC12 cells in the differentiation medium were treated with TRTS at 39.5°C (18 h/day), 40 ng/ml BMP4, or left untreated for 7 days in the presence or absence of 2.5 μM U0126, 2.5 μM U0124, 0.5 μM SB203580, or 1.0 μM GW441756. (A) Representative phase-contrast images of PC12 cells on day 7 after treatment with no stimulation; (B) TRTS (18 h/day); (C) TRTS (18 h/day) plus 2.5 μM U0126; (D) TRTS (18 h/day) plus 2.5 μM U0124; (E) TRTS (18 h/day) plus 0.5 μM SB203580; (F) TRTS (18 h/day) plus 1.0 μM GW441756; (G) 40 ng/ml BMP4; (H) 40 ng/ml BMP4 plus 2.5 μM U0126; (I) 40 ng/ml BMP4 plus 2.5 μM U0124; (J) 40 ng/ml BMP4 plus 0.5 μM SB203580; (K) 40 ng/ml BMP4 plus 1.0 μM GW441756. Scale bar, 100 μm. (L, M) PC12 cells were treated with TRTS at 39.5°C (18 h/day), 40 ng/ml BMP4, or left untreated for 7 days in the presence of the indicated concentrations of U0126, U0124, SB203580, or GW441756. The percentage of neurite-bearing cells on day 7 was assayed. The data represent the mean ± SD of three replicates. ††<i>P</i> < 0.01 vs. the day 7 control with no stimulation. **<i>P</i> < 0.01 vs. TRTS or BMP4 alone on day 7. n.s., not significant. #, not significant vs. the day 7 control with no stimulation. TRTS, temperature-controlled repeated thermal stimulation.</p

The effect of TRTS on cell proliferation of PC12 cells.

<p>(A–L) PC12 cells in cell growth medium were exposed to TRTS at two different temperatures for 18 h/day, or left untreated for 7 days. During TRTS, phase-contrast images were captured on day 0 (A, E, and I), day 3 (B, F, and J), day 5 (C, G, and K), and day 7 (D, H, and L). Phase-contrast images of PC12 cells during incubation without TRTS treatment (A–D); with TRTS at 39.5°C (E-H); or with TRTS at 42.0°C (I-L). Scale bar, 200 μm. (M) PC12 cells in the cell growth medium received TRTS at two different temperatures for 18 h/day, or were left untreated for 7 days, and the number of attached cells on the bottom of the plate was determined. The data represent the mean ± SD of four replicates. ††<i>P</i> < 0.01 vs. the day 0 controls with no stimulation. **<i>P</i> < 0.01. TRTS, temperature-controlled repeated thermal stimulation.</p