Verification of a tree canopy model and an example of its application in wind environment optimization

Haeinsa temple is famous for over 80 000 wooden printing blocks of Buddhist scriptures called Tripitaka Koreana and its storage halls, both of which have been registered as the world cultural heritages by UNESCO. The objective of the present paper is to investigate the ventilation flow in the storage halls of Tripitaka Koreana in the case of building rearrangement in Haeinsa temple. Three-dimensional flow simulations were performed with the detailed geometry of all buildings in the temple. The slatted windows on walls of the storage halls and Tripitaka Koreana stored in the shelves inside the storage halls were modeled in detail to predict reliable ventilation performance. A tree canopy model was also adopted to take into account of the effect of the forest surrounding the temple. Wind velocities as inlet boundary condition were imposed from meteorological statistical data. The numerical results were obtained for the effects of the wind direction, wind speed and tree canopy model on the ventilation performance of the storage halls. It was shown from the numerical results that the ventilation flow distribution at the storage halls in the case of building rearrangement would not be significantly altered compared to that before rearrangement.

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Examining tree canopy models for CFD prediction of wind environment at pedestrian level

Journal of Wind Engineering and Industrial Aerodynamics ◽

10.1016/j.jweia.2008.02.055 ◽

2008 ◽

Vol 96 (10-11) ◽

pp. 1667-1677 ◽

Cited By ~ 75

Author(s):

Akashi Mochida ◽

Yuichi Tabata ◽

Tatsuaki Iwata ◽

Hiroshi Yoshino

Keyword(s):

Tree Canopy ◽

Wind Environment

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Citrus Irrigation Management

EDIS ◽

10.32473/edis-ss660-2017 ◽

2017 ◽

Vol 2017 (5) ◽

Author(s):

Davie Mayeso Kadyampakeni ◽

Kelly T. Morgan ◽

Mongi Zekri ◽

Rhuanito Ferrarezi ◽

Arnold Schumann ◽

...

Keyword(s):

Water Stress ◽

Physiological Activity ◽

Irrigation Management ◽

Fruit Size ◽

Irrigation Scheduling ◽

Leaf Expansion ◽

Tree Canopy ◽

Limiting Factor ◽

Irrigation Frequency ◽

Citrus Production

Water is a limiting factor in Florida citrus production during the majority of the year because of the low water holding capacity of sandy soils resulting from low clay and the non-uniform distribution of the rainfall. In Florida, the major portion of rainfall comes in June through September. However, rainfall is scarce during the dry period from February through May, which coincides with the critical stages of bloom, leaf expansion, fruit set, and fruit enlargement. Irrigation is practiced to provide water when rainfall is not sufficient or timely to meet water needs. Proper irrigation scheduling is the application of water to crops only when needed and only in the amounts needed; that is, determining when to irrigate and how much water to apply. With proper irrigation scheduling, yield will not be limited by water stress. With citrus greening (HLB), irrigation scheduling is becoming more important and critical and growers cannot afford water stress or water excess. Any degree of water stress or imbalance can produce a deleterious change in physiological activity of growth and production of citrus trees. The number of fruit, fruit size, and tree canopy are reduced and premature fruit drop is increased with water stress. Extension growth in shoots and roots and leaf expansion are all negatively impacted by water stress. Other benefits of proper irrigation scheduling include reduced loss of nutrients from leaching as a result of excess water applications and reduced pollution of groundwater or surface waters from the leaching of nutrients. Recent studies have shown that for HLB-affected trees, irrigation frequency should increase and irrigation amounts should decrease to minimize water stress from drought stress or water excess, while ensuring optimal water availability in the rootzone at all times.

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Review for "Research on aerodynamic characteristics of wind turbine airfoil and blade in sand‐wind environment"

10.1002/2050-7038.12541/v2/review2 ◽

2020 ◽

Keyword(s):

Wind Turbine ◽

Aerodynamic Characteristics ◽

Wind Environment ◽

Wind Turbine Airfoil

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Decision letter for "Research on aerodynamic characteristics of wind turbine airfoil and blade in sand‐wind environment"

10.1002/2050-7038.12541/v2/decision1 ◽

2020 ◽

Keyword(s):

Wind Turbine ◽

Aerodynamic Characteristics ◽

Wind Environment ◽

Wind Turbine Airfoil

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Review for "Research on aerodynamic characteristics of wind turbine airfoil and blade in sand‐wind environment"

10.1002/2050-7038.12541/v1/review2 ◽

2020 ◽

Keyword(s):

Wind Turbine ◽

Aerodynamic Characteristics ◽

Wind Environment ◽

Wind Turbine Airfoil

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Spray Volume, Canopy Density, and Other Factors Involved in Thinner Efficacy

HortScience ◽

10.21273/hortsci.33.3.553d ◽

1998 ◽

Vol 33 (3) ◽

pp. 553d-553

Author(s):

C.R. Unrath

Keyword(s):

Tree Height ◽

Tree Canopy ◽

Tree Size ◽

Water Volume ◽

Canopy Density ◽

The North ◽

Run Off ◽

Tree Canopies ◽

Average Water ◽

Water Volumes

Historically, most airblast chemical applications to apple orchards used a single “average” water volume, resulting in variability of coverage with tree size and also the greatest variable in chemical thinning. This coverage variability can be eliminated by properly quantifying the tree canopy, as tree row volume (TRV), and relating that volume to airblast water rate for adequate coverge. Maximum typical tree height, cross-row limb spread, and between-row spacing are used to quantify the TRV. Further refinement is achieved by adjusting the water volume for tree canopy density. The North Carolina TRV model allows a density adjustment from 0.7 gal/1000 ft3 of TRV for young, very open tree canopies to 1.0 gal/1000 ft3 of TRV for large, thick tree canopies to deliver a full dilute application for maximum water application (to the point of run-off). Most dilute pesticide applications use 70% of full dilute to approach the point of drip (pesticide dilute) to not waste chemicals and reduce non-target environmental exposure. From the “chemical load” (i.e., lb/acre) calculated for the pesticide dilute application, the proper chemical load for lower (concentrate) water volumes can be accurately determined. Another significant source of variability is thinner application response is spray distribution to various areas of the tree. This variability is related to tree configuration, light, levels, fruit set, and natural thinning vs. the need for chemical thinning. Required water delivery patterns are a function of tree size, form, spacing, and density, as well as sprayer design (no. of nozzles and fan size). The TRV model, density adjustments, and nozzle patterns to effectively hit the target for uniform crop load will be addressed.

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Nutrient Concentrations in Soil Solution in an Alfisol under Grapefruit Production

HortScience ◽

10.21273/hortsci.33.3.498d ◽

1998 ◽

Vol 33 (3) ◽

pp. 498d-498

Author(s):

Z.L. He ◽

A.K. Alva ◽

D.V. Calvert ◽

D.J. Banks ◽

Y.C. Li

Keyword(s):

Soil Solution ◽

Fine Sand ◽

Drainage Water ◽

Tree Canopy ◽

Nutrient Concentrations ◽

Sour Orange ◽

Parallel Study ◽

Ph Measurements ◽

The Mean ◽

N Rates

A field experiment was conducted in a Riviera fine sand (Alfisol) with 25-year-old `White Marsh' grapefruit trees on Sour orange rootstock to monitor the downward transport of nutrients from fertilization practices. Fertilizer was applied as either dry granular broadcast (three applications/year) or fertigation (15 applications/year) at N rates of 56, 112, 168, and 336 kg/ha per year using a N:P:K blend (1.0:0.17:1.0). Soil solution was sampled bi-weekly from suction lysimeters, installed under the tree canopy, about 120 cm from the tree trunk, at two depths representing above (120 cm) and below (180 cm) the hard pan. The concentrations of K, Ca, and Mg were greater at the 180- than at 120-cm depth, whereas, the converse was true with respect to the concentration of P in soil solution. Over a 2-year period, the mean concentrations of P and K varied from 0.031-0.976 and 150-250 mg·L–1, respectively. Increased rate of fertilization also appeared to increase the concentrations of Ca and Mg in the soil solution. This could be due to effects of slight acidification of the soil with increased rates of ammonium form of N. A parallel study on pH measurements has shown evidence of soil acidification, under the tree canopy, with increased rates of ammonium fertilization. In a bedded grove, the soil solution above the hard pan is likely to seep into the water furrow, which is discharged into the drainage water.

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