Study on the Natural Ventilation Model of a Single-Span Plastic Greenhouse in a High-Altitude Area
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsReaders might expect specific findings in greenhouse natural ventilation mechanism in high altitude area based on the title, but the main text does not necessarily meet those expectations. Revising the structure to better meet those expectations could make the manuscript superior.
Comments that may require major revisions:
Line 146
I’m wondering that the authors have not included the species equation including water vapor, because the equation is essential to calculate transpiration and crop leaf temperature.
Line 412
I’m wondering how the authors have derived Tc which determined by a heat balance equation of leaves considering transpiration.
Line 488
In my experience of greenhouse natural ventilation using CFD, crop height has also an impact on the ventilation rate. However, the authors have demonstrated it in just one case of crop height. I’m wondering that the authors need to prepare more sets of variables in the natural ventilation equation like Eq. 21 for the purpose of this study.
Other comments:
Line 98
The description of materials and methods should be written in past form.
Line 111
It would be better to add plant density like xx plants per m2.
Line 113
The font size in this figure and the followings should be larger.
Line 125
Please describe that the sensors of indoor and outdoor air temperature were aspirated or not.
Line 183
I suggested adding an explanation of the necessity of DO model in the calculation in high altitude.
Line 224
I’m wondering that the models of ra and rs have been derived from crops grown in high altitude area.
Line 299
Good accuracy was found. I suggest adding how the accuracy of spatial distribution in the greenhouse of air temperature was.
Line 310
The range of vertical axis of both figures should be aligned.
Line 388
The authors measured the spatial gradients of air temperature. Have the results of the field experiment supported the assumption (1)?
Line 512
I suggest adding how the authors have derived the results shown in Fig 12.
Line 526
The section from line 526 onward appears to only explain known results and may therefore be unnecessary.
Comments on the Quality of English LanguageIn terms of the writing style for papers in this field, I find the following terms unusual as they are not commonly seen in previous literature: facility vegetable industry (line 31), facility environment regulation (line 40), heat pressure ventilation (line 512). I think it would be better to revise them.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe paper displayed a Study on the Natural Ventilation Model of a Single-Span Plastic Greenhouse in a High-Altitude Area. However, the natural ventilation plays a crucial role in greenhouse environmental control. The following comments are considered.
1.What is the range to say an area has high altitude area?
2.Can the developed model be applied to glass greenhouses.
3.Pleas give advantages and disadvantages of high and low altitude areas in the cultivation of vegetables.
4.The authors wrote” However, compared to low-altitude areas, the Tibet region has environmental characteristics such as low air pressure, strong solar radiation, and great temperature variation between day and night, so what about the air relative humidity and wind speed levels.
5.Line 189: I is the solar radiation intensity. Is it total solar radiation on horizontal surface
6.Line 208: CD is the drag coefficient, with a value of 0.2. Please give justifications for such value
7.The data in Table 2 representing Basic parameters of greenhouse materials and this information need a reference.
8.Line 242: what is the SIMPLEC algorithm.
9.All Figures need improvements.
10.Can you link the ventilation rate with crop growth rate.
11.What about the heat unit requirements for the crop in the high and low attitude areas as great temperature variation between day and night are appeared in the low-altitude areas.
12. You should give some details about the single-span plastic greenhouses.
13. is there effect of characteristics Plastic film on the performance of ventilation flow.
14.How do you calculate the Ac (the surface area of the crops inside the greenhouse) value?
15. Line 412: the authors wrote “the greenhouse, K; Tc is the temperature of the crop surface inside the greenhouse, K; since the heat flow caused by cold air infiltration is much smaller than that caused by ventilation, Φal can be neglected here. Is this the only reason to neglect , Φal or there are hidden reasons.
16. how do you derived the ventilation rate model as appareled in Equation (21).
17. Pleas identify the symbols in equation 21.
18. Is the size of the greenhouse has an effect on the performance of ventilation flow?
19. Please give details how do you measure all temperatures.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsNo comments
