Campbell-scientific Bowen Ratio Instrumentation Manual de usuario

INSTRUCTION MANUALBowen Ratio InstrumentationRevision: 9/05Copyright (c) 1987-2005Campbell Scientific, Inc.

Section 1. System Overview 1-6 This is a blank page.

2-1 Section 2. Station Installation Figure 2-1 shows the typical Bowen ratio installation on the CM10 tripod. The 023A enclosure, mounting arms, and

Section 2. Station Installation 2-2 Q7-BR(system) FIGURE 2-1. CSI Bowen Ratio System 2.2 Soil Thermocouples and Heat Flux Plates The soil thermocou

Section 2. Station Installation 2-3 To minimize thermal conduction down the sensor lead wires, they should be buried for a short distance back from t

Section 2. Station Installation 2-4 FIGURE 2.2-2. TCAV Spatial Averaging Thermocouple Probe 2.3 Wiring Table 2.3-1 lists the connections to the CR

Section 2. Station Installation 2-5 UPPER/LOWER TCs - CONSTANTAN RED/RED TC SHIELD CLEAR/CLEAR 5H HFT#1 BLACK 5L HFT#2 WHITE/WHITE HFT#1 AND

Section 2. Station Installation 2-6 CR23X FIGURE 2.3. A Block Diagram for the Connections between the Datalogger, the BR Relay Driver and Component

Section 2. Station Installation 2-7 2.4 Battery Connections Two terminal strip adapters for the battery posts (P/N 4386) are provided with the 023A

Section 2. Station Installation 2-8 thermocouples. A camel-hair brush and tweezers can be used to clean the thermocouples. To turn the hygrometer a

Section 2. Station Installation 2-9 If the LED is not already on, turn the potentiometer clockwise until it turns on and then counter clockwise unt

Warranty and Assistance The BOWEN RATIO INSTRUMENTATION is warranted by CAMPBELL SCIENTIFIC, INC. to be free from defects in materials and workmanship

Section 2. Station Installation 2-10 This is a blank page.

3-1 Section 3. Sample CR23X Program The example program is available on the Campbell Scientific FTP site, ftp://ftp.campbellsci.com/pub/outgoing/file

Section 3. Sample CR23X Program 3-2 TABLE 3-1. Sample CR23X Bowen Ratio Program Flow Chart Table 1 1 Second Execution Interval Measure Panel Tempera

Section 3. Sample CR23X Program 3-3 Table 2 10 Second Excitation Interval Yes 40 Second Interval ? No Reset Flag 1 Yes Flag 5 Set ? No Yes

Section 3. Sample CR23X Program 3-4 Subroutine 1 Output the time processing is re-enabled Reset Flag 5 (Re-enable Output) [output process] Day, Ho

Section 3. Sample CR23X Program 3-5 TABLE 3-2. Output From Example Bowen Ratio Program 01: 110 20 minute Bowen ratio data 02: Day 03: hhmm 04:

Section 3. Sample CR23X Program 3-6 This is a blank page.

4-1 Section 4. Calculating Fluxes Using SPLIT SPLIT (LoggerNet software) can be used to calculate the fluxes from the Bowen ratio measurements. This

Section 4. Calculating Fluxes Using SPLIT 4-2 heat of the soil and the change in soil temperature, ∆Ts, over the output interval, t, are required to

Section 4. Calculating Fluxes Using SPLIT 4-3 TABLE 4.2-1. Input Values for Flux Calculations VARIB. VALUE UNITS DESCRIPTION CP 1.01 kJ/(kg K)

i Bowen Ratio Table of Contents PDF viewers note: These page numbers refer to the printed version of this document. Use the Adobe Acrobat® bookmarks

Section 4. Calculating Fluxes Using SPLIT 4-4 This is a blank page.

A-1 Appendix A. References Bowen, I. S., 1926: The ratio of heat losses by conduction and by evaporation from any water surface. Phys. Rev., 27, 779

Appendix A. References A-2 Wallace, J. M., and P. V. Hobbes, 1977: Atmospheric Science: An Introductory Survey. Academic Press, 350 pp.

B-1 Appendix B. 023 Bowen Ratio (Pre July 1993) FIGURE B-1. 023 Bowen Ratio Vapor Measurement System with Three Flowmeters

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Campbell Scientific CompaniesCampbell Scientific, Inc. (CSI)815 West 1800 NorthLogan, Utah 84321UNITED [email protected]

Bowen Ratio Table of Contents ii Figures 1.2-1. Vapor Measurement System...1-3 1.2-2. Ther

1-1 Section 1. System Overview 1.1 Review of Theory By analogy with molecular diffusion, the flux-gradient approach to vertical transport of an ent

Section 1. System Overview 1-2 ()()βλε==−−HLPCTTeeep1212 (6) where PCpλε is the psychrometric constant. The surface energy budget is given by, RGHL

Section 1. System Overview 1-3 FIGURE 1.2-1. Vapor Measurement System 1.2 System Description 1.2.1 Water Vapor Measurement It is common practice

Section 1. System Overview 1-4 A datalogger is used to measure all sensors and control the valve that switches the air stream through the cooled mirr

Section 1. System Overview 1-5 the gradient measurement is due only to the difference in the radiative heating of the two TC junctions and their phys