Environmental Engineering Reference
In-Depth Information
Table 2. Plant design conditions assumed for design of test plant
Design parameter
Assumed value/range
5,000 kcal/m
2
day (annual mean value on horizontal surface)
Solar radiation
30
o
C (daytime mean temperature)
Ambient temperature
Rainfall
18.1 - 390.1 mm/year
Wind speed
5 m/s (for collector design)
30 m/s (for structures)
Relative humidity
Max. 100%, min. 10%, normal 25-90%
Seawater temperature
55,000 ppm TDS (design base)
80 m
3
/day as expected yearly average
System capacity
Solar collector type
Evacuated glass tube collector
1862 m
2
(effective absorbing area)
Heat accumulator
Thermally stratified vertical cylinder
Capacity 300 m
3
Evaporator
Horizontal-tube, multiple effect stack type
Evaporator, capacity 120 m
3
/day, specific heat consumption
43.8 kcal/kg- product water
4. Measurements and Data Acquisition System
Table 3 lists the plant parameters measured every 15 minutes and sent to the data
acquisition system (DAS). The DAS is shown in figure 8 and consists of two separate
subsystems: one is the on-line control room subsystem and the other is the data analysis
subsystem. The data analysis subsystem consists of a Thermodac 32 data logger
manufactured by Eto Denki, Co., PC (model PC-8001 mkII manufactured by NEC company)
and a PC printer (model PC-8023C manufactured by NEC company). The data analysis
subsystem consists of a data logger (model Thermodac 3 manufactured by Eto Denki, Co.),
PC (model PC-8801mk II by NEC company) and PC printer (model PC-8024 by NEC
company).
The on-line control room subsystem has the following functions:
•
Sampling of data at 15 minute intervals
•
Calculate hourly average values once per hour
•
Record data on CD at even hours (i.e. 8:00, 10:00, 12:00,…)
•
Print a summary report every 12 hours.
The data analysis subsystem has the following functions:
•
Make daily, weekly and monthly reports.
•
Format new data disks
•
Copy data disks for backup
•
Edit hourly or daily data on data disks.
Search WWH ::
Custom Search