Armfield S12-MKII User manual

Advanced Environmental
Hydrology System
Instruction Manual
S12-MKII
ISSUE 21
February 2014

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Table of Contents
Copyright and Trademarks...................................................................................... 1
General Overview ....................................................................................................... 2
Equipment Diagrams................................................................................................... 4
Important Safety Information....................................................................................... 7
Introduction.............................................................................................................. 7
Electrical Safety....................................................................................................... 7
Heavy Equipment.................................................................................................... 7
Water Borne Hazards.............................................................................................. 7
The COSHH Regulations ........................................................................................ 8
Description................................................................................................................ 10
Overview................................................................................................................ 10
Frame.................................................................................................................... 10
Water Feeds.......................................................................................................... 10
Sand Tank............................................................................................................. 11
Outlet Collecting Tank........................................................................................... 12
S12-MKII-50 (S12-MKII Including Data Logging and Educational Software)........ 12
Overhead Spray Nozzles....................................................................................... 13
River Inlet Tank ..................................................................................................... 13
Choice of Granular Material for the Sand Tank..................................................... 14
Accessories........................................................................................................... 14
Installation................................................................................................................. 16
Advisory................................................................................................................. 16
Electrical Supply.................................................................................................... 16
Cold Water Supply................................................................................................. 17
Laboratory Drain.................................................................................................... 17
Installing the PC Software (Version S12-MKII-50 only)......................................... 17
Installing the Equipment........................................................................................ 18
Commissioning...................................................................................................... 19
Electrical Wiring Diagram...................................................................................... 21

Table of Contents
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Operation .................................................................................................................. 22
Operating the PC Software.................................................................................... 22
Operating the Equipment....................................................................................... 24
Equipment Specifications.......................................................................................... 25
Equipment Location............................................................................................... 25
Electromagnetic Compatibility............................................................................... 25
Environmental Conditions...................................................................................... 25
Routine Maintenance................................................................................................ 26
Responsibility ........................................................................................................ 26
General.................................................................................................................. 26
Load Sensor.......................................................................................................... 28
Laboratory Teaching Exercises................................................................................. 29
Index to Exercises................................................................................................. 29
General Equations and Constants......................................................................... 29
Exercise A - Rainfall-runoff relationships (storm hydrographs)................................. 32
Exercise B - Generation of overland flow.................................................................. 37
Exercise C - Initiation and characteristics of bedload motion.................................... 39
Exercise D - Effect of changing stream power on channel morphology.................... 42
Exercise E - Effect of base level change................................................................... 45
Exercise F - Scour in open channel flow................................................................... 47
Exercise G - Water abstraction from a well in a confined aquifer ............................. 49
Exercise H - Water abstraction from a well in an unconfined aquifer........................ 53
Exercise I - Water abstraction from a number of neighbouring wells........................ 56
Exercise J - Rainfall on a circular island with a central well...................................... 59
Exercise K - Ground water flow between two canals with and without rainfall.......... 61
Contact Details for Further Information..................................................................... 63

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Disclaimer
This document and all the information contained within it is proprietary to Armfield
Limited. This document must not be used for any purpose other than that for which it
is supplied and its contents must not be reproduced, modified, adapted, published,
translated or disclosed to any third party, in whole or in part, without the prior written
permission of Armfield Limited.
Should you have any queries or comments, please contact the Armfield Customer
Support helpdesk (Monday to Thursday: 0830 - 1730 and Friday: 0830 - 1300 UK
time). Contact details are as follows:
United Kingdom International
(0) 1425 478781
(calls charged at local rate) [phone] (international rates apply)
Email: [email protected]
Fax: [phone]
Copyright and Trademarks
Copyright © 2014 Armfield Limited. All rights reserved.
Any technical documentation made available by Armfield Limited is the copyright
work of Armfield Limited and wholly owned by Armfield Limited.
Brands and product names mentioned in this manual may be trademarks or
registered trademarks of their respective companies and are hereby acknowledged.

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General Overview
This floor-standing unit is the only Hydrology System that includes features making it
suitable for studying fluvial geomorphology. It combines the capabilities of the S10
Rainfall Hydrographs and S11 Ground Water Flow Unit into a single comprehensive
facility. The system is fully instrumented for investigation of rainfall/run-off
hydrographs, ground water abstraction studies and unique to this apparatus, fluvial
mechanics.
This apparatus sets out to demonstrate, on a small scale, some of the physical
processes found in hydrology. These processes fall into two related categories: the
relationship between rainfall and run-off from catchment areas of varying permeability
and the abstraction of ground water by wells, both with and without surface recharge
from rainfall.
Thus it can be seen that it is concerned with that part of the hydrological cycle
bounded by the arrival of "net rainfall" on the ground surface and catchment run-off
either by surface streams or well abstraction.
The hydrological cycle describes the complete movement of water between the
atmosphere, the land surfaces and the water masses of the earth. There are a
number of possible routes that water can follow in moving round this cycle and these
are outlined below.
Precipitation (rainfall) on the land surfaces is disposed of in various ways. What
water remains after the ground has been wetted and evaporation and transpiration
losses have been deducted, is termed the "net rainfall" and this may
i. soak into the ground (infiltrate) to join the ground water held in voids (normally
very small)
ii. fill up surface depressions to form puddles, or
iii. any remaining will flow over the ground surface in the downhill direction to
form streams and, subsequently, rivers.
Ground water also flows laterally under the influence of slopes, to reappear at the
surface either to form springs or to increase stream flow by reverse infiltration
through the bed.

General Overview
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Abstraction from wells is another way in which water can leave a catchment area and
it can, therefore, be thought of as forming part of the run-off.
A proper understanding of these processes and their inter-relationships is essential
for many purposes. Engineers are commonly concerned with the provision of water
supplies for urban and irrigation needs; with the estimation of flood magnitudes and
frequencies; with the consequences of land drainage works on flood risks, on the use
of wells to de-water construction excavations and the drainage of lakes and polders.
Geologists and geographers are frequently faced with problems which involve
hydrological processes such as drawing up a water balance for a catchment area,
the investigation of morphological processes in rivers and streams, and the control of
mud flows and soil erosion caused by surface and sub-surface water flows.
The range of experimental capabilities is significantly increased by the provision of a
river inlet tank and outlet collecting tank. These enable a range of fluvial mechanics
experiments to be carried out in related topics such as river flow and sediment
transport, initiation and characteristics of bed-load motion, general and local scour in
open channel flow etc.

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Equipment Diagrams
Figure 1: Front View of S12-MKII Hydrology System

Equipment Diagrams
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Figure 2: Plan View of S12-MKII Hydrology System

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Figure 3: End View of S12-MKII Hydrology System