Abstract
The author calculated the standard values of the latent load for the air-conditioned glasshouse growing tobacco plant.
From the standard radiation at outside of 824 kcal/m2⋅h, the standard values of incoming radiation of 602 kcal/m2⋅ h and 3, 926 kcal/m2⋅ day were obtained. Using the empirical formula of radiation (Si↓) and evaporation (LE), LE=0.554 Si↓-4.60 (cal/ cm2⋅h), we also obtained the standard values of evaporation (LE) of 288 kcal/m2⋅ h and 2, 880 kcal/m2⋅ day.
The ratio of plant growing bed area to room area, designated as the bed ratio (B), was investigated at various glasshouses and found 0.60±0.025. If the utilization ratio of the bed by the plant pots, named the plant occupation ratio (U), and the covering ratio by plant leaves on bed, named the shade ratio (γ), are decided to the crop kinds and the using condition of room etc., we can calculate the latent load (pLE) by the following equation.
pLE=LE×B×U×γ
For tobacco plant, B=0.60±0.025, U=1.0, γ=0.93±0.05, the standard values of the latent load for design are 161±15 kcal/m2 (room) ⋅h, 275g/m2 (room) ⋅ h and 1, 610±150 kcal/m2 (room) ⋅day, 2, 750 g/m2 (room) ⋅ day.
