Presentation on theme: "MATLAB based design software for greenhouse evaporative cooling system Wei Fang Dept. of Bio-Industrial Mechatronics Engineering National Taiwan University."— Presentation transcript:
MATLAB based design software for greenhouse evaporative cooling system Wei Fang Dept. of Bio-Industrial Mechatronics Engineering National Taiwan University
Objective –Develop Software for the design of pad and fan system
Proper design Bleed off end Bleed off tube to floor drain or outside
wet bulb depression Typical WBD (wet bulb depression) of plain area in Taiwan
Max. T drop using Fad&Fan in Taiwan oCoC % WBD (Wet Bulb Depression) = dry bulb Temperature – wet bulb Temperature T = WBD * Efficiency
Software development Tool MATLAB (Mathworks, USA) Popular among Engineers Recent Textbook in Agr. Eng. –Takakura and Fang (2002) : Climate under cover -- dynamic simulations of bio- engineering systems using MATLAB. Kluwer Academic Publisher. –Cundiff and Mankin (2003) ： Dynamics of biological systems. ASAE.
PFD (Pad_Fan_Design) Input ： Dimension of GH Design criteria Number of fans Types of Pad Output ： System operating curves Fan curves & pressure drop curves Drawings of GH in 3D Length of Pad required Flow rate of P ump Size of S ump Makeup water required
PFD window 1 Enter GH dimension –Metric,or English units Type of roof –3 types available Interval between posts No. of bays per post Misc.
PFD window 2 Select 1 algorithm out of 3 –NGMA/ACME –Munters –Air change ROT
PFD window 3 Number of fan required (guess value) (guess value) –9 models of Euromme fans Select type of pads –4 types available Design facing velocity Extra pressure drop Required pad area, length Calculated pump flow rate Calculated sump size Calculated makeup water
PFD window 3 Display Fan & pad curves In m 3 /s, in m 3 /m 2 /min In m 3 /s, in m 3 /m 2 /min Display GH in 3D Show more info. on Pads
Conclusion 1 The software developed can be served as teaching/research/design tool. The software allows users to pick their options from currently available commercial products most popular in Taiwan, including ： –9 fans ， 4 pads –3 roofs ， –3 design criteria
Conclusion 2 The software provide fool proof design ， including ： –Interval between fans installed to check too much or too little fans –Comparison on Pad length and GH length The software provide flexible outputs ， including ： –Fan curves, pad curves and system operating point –GH drawings in 3D and allow for rotate,zoom in and out –P ump, sump, makeup water requirement