Measurement and prediction of greenhouse ventilation rates
Measurement and prediction of greenhouse ventilation rates
复制标题
温室通风率的测量和预测
DOI：
10.1016/0168-1923(92)90063-a
复制
发表时间：
1992
影响因子：
6.2
通讯作者：
B. J. Bailey
中科院分区：
文献类型：
--
作者：
J. Fernández;B. J. Bailey
在种植成熟番茄作物的多跨温室中测量自然通风和泄漏率。通风率测量采用四种设置的背风通风机（最大开口的 10%、20%、30% 和 40%）进行。分析了风速、风向和内外温差的影响。泄漏和通风率测量是通过使用 N2O 的动态示踪气体方法进行的。发现风速对泄漏和通风率都有很大影响。没有观察到风向和温差的影响，但实验是在有风的地区进行的，很难确定后一个参数的影响。获得了每个通风机位置预测空气交换与风速函数的公式。推导了单位通风机面积的通风通量和平均风速与打开角度的函数（G（α）函数）的另一个公式。使用温室的能量平衡模型预测通风率。能量平衡模型预测的值与较大通风口的测量值之间具有良好的一致性，但在低通风率时，一致性较差。将获得的结果与使用其他作者开发的模型获得的结果进行比较。这使得侧壁渗透率对通风率的影响得以确定。
Natural ventilation and leakage rates were measured in a multispan glasshouse with a mature tomato crop. The ventilation-rate measurements were made with four settings of the leeward ventilators (10, 20, 30 and 40% of the maximum opening). The influences of wind speed, wind direction and inside-outside temperature difference were analysed. The leakage and ventilation rate measurements were made with the dynamic tracer-gas method using N2O.Wind speed was found to have a strong influence on both leakage and ventilation rates. No influence was observed from either wind direction or temperature difference, but the experiments were carried out in a windy area, where it was difficult to determine the influence of the latter parameter. A formula to predict the air exchange as a function of wind speed was obtained for each ventilator position. Another formula was derived for the ventilation flux per unit ventilator area and average wind speed as a function of the opening angle (G(α) function).Ventilation rates were predicted using an energy balance model of the greenhouse. Good agreement was obtained between values predicted by the energy balance model and the measured values for larger ventilator openings, but at low ventilation rates the agreement was poor. The results obtained were compared with those obtained using models developed by other authors. This enabled the influence of side-wall permeability on ventilation rate to be established.