| Solar greenhouse is widely used in agricultural production in China. Agricultural facilities is an efficient way of agriculture production in the condition of relatively controllable environment. In 2015, the area of facility agriculture in China accounted for more than 80% of the total area of the world. The technology level of our country is closer and closer to the world advanced level. The development of facility agriculture can effectively solve the problem of many people in our country. The soil temperature in solar greenhouse was studied.The results of this study are as follows:1. The influence of ground temperature on the indoor temperature in the solar greenhouse is mainly influenced by the things on both sides of the walls, the south wall and north to exchange and transfer between the wall and soil heat insulation. Under the same weather condition, the West gable surrounding soil diurnal variation range is greater than that of the East gable. The south wall diurnal variation of soil temperature is greater than that in the North back wall. The daily temperature change of the north side of the rear wall is:wall range> outdoor soil range> indoor. The ground temperature of the greenhouse changed significantly with the daily change of the solar altitude, and the north to the base was constant.2. The influence of temperature on the south side of solar greenhouse is:In winter on the south side of the horizontal direction from the outside wall in the range of 30cm good weather conditions has freezing and thawing cycle. The daily variation of temperature range of 10cm is 15.6?, and the range of 20cm is 9.3?, and the range of 30cm is 5.8?. Under the influence of 30cm outside the frozen soil, the temperature is below 0?, and there is no thawing phenomenon. Study on greenhouse outside the south side 30cm is arranged in accord with the results of cold proof ditch. On a winter temperature significantly inflection point is the horizontal distance within the scope of 40cm-100cm mobile, more than 100 cm soil temperature diurnal variation was moving average function change, no longer is polynomial in obvious peak and valley value.3. The influence of temperature on the east and west side of solar greenhouse is:Effect of distance in the range of 20cm is mainly affected by the gable gable heat storage. The West gable outdoor range of 30cm, after reaching a peak in the afternoon temperature decreased slowly. The time to reach the valley was 10h. The slope of the curve tangent is k=-0.76, and the slope of the temperature rise k=1.49 is very large. The time to peak later than the west side, respectively 14:00 and 15:30. The same distance between the two sides of the same room temperature changes, the main point of the survey is mainly affected by the indoor temperature changes in the day. The curve of the variation curve shows the average moving function, which is consistent with the change trend of the temperature in the middle of the greenhouse, but the range is less than the temperature point.4. The influence of temperature on the north side of solar greenhouse is:The outdoor level measuring points only show the maximum temperature of measuring points at 10cm distance of 0.6?. The rest of the day were monitored in outdoor measuring point below 0 ?. The temperature change curve of each measurement point is shown as the distance from the north wall, the more recent temperature range is smaller.10cm,20 cm,30 cm,40 cm,50 cm, 60 cm temperature range were 1.6?,2.3?,3?,3.8?,4.2?,5.9?Temperature is at a low level, close to the lowest temperature of 6.1 degrees celsius. On the north side of the indoor temperature change is greater than the distance from the beginning of 1m and indoor air temperature daily variation trend is similar, lm are average moving function, and the change trend is moderate. North wall depth 30cm of the measuring point temperature change curve similar to spindle. Minimum temperature performance. The maximum temperature is 9?, 11 ?,13.8?,17?,22.5?,26?. The maximum temperature is increased with the advance of shallow depth.The influence of the surrounding ground temperature on the indoor temperature is shown as the change of temperature field and the significance of the marginal effect in different directions. In the middle of November 2015, the indoor soil showed obvious marginal effect on the south side of 110cm. In the cold January, the south side of the point of the distance 260cm. In summary, the influence of the temperature on the indoor ground temperature is studied by the above mentioned above. The influence distance of ground temperature and the difference of the marginal effect of soil temperature are different. The time of the emergence of the peak temperature will be corresponding to advance or delay. Considering the greenhouse structure and cold proof measures of heat preservation materials, it needs to maintain relatively stable environment in greenhouse. |
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