A New or Improved Method of and Apparatus for Measuring the Rate of Flow of Liquids, Steam, or Gases, through Tubes, and for Mixing or Delivering them in Given Proportions or Quantities and for like Purposes.
Year: 1899

page_text: Date of Application, 31st Oct., 1899-Accepted, 27th Oct.,
1800
COMPLETE SPECIFICATION.
A New or Improved Method of and Apparatus for Measuring the Rate
of Flow of Liquids, Steam, or Gases, through Tubes, and for Mixing
or Delivering them in Given Proportions or Quantities and for like
Purposes.
I, Dr HERMANN RADE, of 15, Toigowaja, Quart 42, St Petersburg, Russia,
Chemist, do hereby declare the nature of this invention and in what manner the
same is to be performed to be particularly described and ascertained in and
by the following statement.-
According to a well-known physical law the volume of a gas or a liquid pass-
ing through any opening depends upon the relative pressures on either side of
the volume of gas or liquid In some known forms of measuring apparatus
constructed upon this principle a fixed contraction in the tube through which
the liquid on gas passes is emploved, and the varying velocity of the fluid in the
tube is measured by the reduction of pressure caused thereby The total cross-
section of the contraction corresponds in such forms of apparatus to the mean
velocity from which to calculate, while very low and very high velocities that is
to say the extreme velocities, cannot be calculated with sufficient accuracy and
fiequently not at all, for the reduction of pressure varies as the square of the
velocity, and the results are therefore too small for low velocities and too great
for high ones
These deficiencies have therefore led the inventor of the present method of
measurement to construct a resistance consisting of a throttling device, which can
be adjusted to the varving velocities of the fluid without interrupting its flow,
and which also will shew visibly the size of the throttled passage or in other
words the degree of throttling for any position in which it may be set
To this end therefore a valve, cock, slide or similar device is employed or any
mechanism which can be opened or closed for the attainment of a predetermined
difference of pressure
The new method of measurement is practically similar
to a weighing operation in which the load 18 approximately counterpoised with
weights, and the remaining difference measured upon a scale upon the scale
beam, whereas in the method employed when using the known apparatus before
referred to, the subsidiary scale alone is emploved
Apart from the fact that according to this present invention the velocities of
gaseous and liquid fluids are enabled to be estimated within a very wide range,
by means of a single piece of apparatus and under any difference of pressure.
the apparatus forming the subject of the present invention may be made of
extremely small size, in the form of a very short manometer tube, its shortness
being compensated for, by the adjustable throttling device
Furthermore the improved apparatus permits of the throttling action being
suspended (without interrupting the flow of the fluids) whenever desired, and
FO allowing them to fill the whole cross sectional area of the tube, an operation
which is frequently necessary when dealing with liquids to remove stoppages
in the pipes, or to control the cross sectional area of the throttling device.

page_text: There will now be described with reference to the sectional views Figs. 1 to 6
of the accompanying diawing, examples of apparatus constructed according to
this invention employed in the herein described improved measuring method
for gases and liquids.
In the example shewn in Figure 1 of the accompanying drawing the tube a
filled through the whole of its cross sectional area with any suitable liquid 18
provided with a cock b fitted externally of its barrel with any suitable aangement
(not shown in the drawings) for shewing the graduated throttling of the fluid
by the cock In front of, and also behind the cock b, the ends, of a U tube f
are inserted in the tube a at d and e
The tube is provided at the top with a bianch closed by a cock and serving
to admit a medium, such as an oi gas, for the purpose of shutting off both
limbs of the U tube The regulation of the flow of the liquid is effected in the
usual way by a cock in the tube a, placed either in front of, or behind the cock b
This regulating cock is not shewn in the diawings
The cocks should be so adjusted relatively to the volume of liquid passing
through the tubes that the difference of pressure may be read off from both
limbs of the tube both in front of, and behind the cock b
In the example shewn in Figs 2 and 3 a modified method of attaching
the tube to the tube a 18 shewn Two horizontal passages h and leading
from the interio of the tube a and parallel with the conical external sui face
of the cock b, are formed in the shell e of the cock, and communicate with the
vertical curved ports and surrounding the plug of the cock, and in the mouths
of these curved ports are inserted the extremities of the limbs of the U tube f
The same apparatus may be employed for measuring both gases and vapours,
but as the gas is lighter than the medium employed for sealing the tube f, the
tube must in such case be provided with an extra U bend m turned downwards
as shewn in Fig 4, and the branch placed at 18 lowest point The tube f may
however be of the form shewn in Fig 1, but must then be attached to the under-
side of the tube a with its head downwards
4
The same principle of measurement may be employed for the mixing of two
gaseous or liquid substances oi of gaseous and liquid substances, or of delivering
gaseous or liquid substances, or gaseous and liquid substances into two volumes
by providing the mixing or sepainting vessel, with an arrangement for suitably
varying the proportions of the resistances in the two bianch tubes. When the
differences of pressure in the branch tubes have been measured, the proportions
of the volumes passing through the tubes may be ascertained by observing the
respective ratios of the throttlings produced
A special application of the above described method of measuring, is the mix-
ing of liquids, gases or vapours, or the separation of the same into different
volumes in definite proportions It will only be necessary, after having once
adjusted the regulating devices (eg cocks) of the bianch tubes, by means of
the resistance controlling devices, to equalise the pressure in both the branch
tubes and to correct any inequality of pressure caused by any valuation of
velocity in either branch tube, by reducing it to its proper ratio by means of
the regulating devices and so levelling the pressure again.
A form of construction of the apparatus employed for carving out this method
18 illustrated at Figs 5 and 6 In these figures is shewn a three way cock, the
branches m and n of which may serve either as inlets, as indicated by the full line
arrows, when mixing, or as outlets as indicated by dotted arrows, when separating,
and the bianch either as an outlet when mixing or an inlet when separating
The plug of the cock, when in the position shewn in the diawings, presents the
same amount of resistance to fluids entering at both m and n, but no resistance
to fluids entering at o On the other hand when turned in a clockwise direction,
one of the branches (in the present case m) may be completely cut off while the
remaining two, n and o, are wide open However if the cock is not turned
beyond certain mit, the ratio of the resistance in the banch tubes m and n
"

page_text: relatively to the fully open branch o may be varied within very wide limits
The branches m and n communicate as in Figs 2 and 3 by ports 2, 1, h and k,
with the limbs of a manometer tube, on which the ratio of the pressure in the
two branch tubes may be read off.
When mixing two gaseous or two liquid substances, or gaseous and liquid
substances, then at the point at which the substances mix, e, in the outlet o,
the pressure will be the same for both branch tubes m and n, therefore this
pressure in the outlet o can be neglected, and it is only necessary to observe the
difference of the pressures existing in the branch tubes m and n by which
pressures the proportions of the quantities entering into the main tubes o are
regulated
When separating two gaseous or two liquid substances, or gaseous and liquid
substances as before mentioned, the pressure before the plug b (in the inlet o)
18 the same for both branch tubes m and n, and therefore in this case it 18 also
only sufficient to state the difference of the pressure existing in the branch tuber
m and n
If it is desired to preseive an equality of pressure in the apparatus, and to
observe the same, it is preferable, more especially when dealing with liquids
of different specific gravities, and also in the case of gases on the one side and
liquids on the other sides, to anange the manometer tube horizontally, which
facilitates the detection of any tendency for them to pass over from one limb into
the other The regulating devices for the branches m and n such as cocks or the
like, as well as the device for the external observation of the position of the
cock b, are not shewn in the drawings.
The production of a mixture or a separation in fixed proportions is effected
as follows The parts being in the position shewn in Fig 5 the regulating
devices of the branches m and n are adjusted in the necessary way, and then the
cock turned till the manometer tube shews that the pressure is equalised Any
signs of a difference in pressure indicate a variation in the ratio of the volumes
of fluid entering the apparatus, which however may be again equalised by
adjusting either of the regulating devices of m or n
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim 18
-
1. The method for measuring the velocity or rate of flow of gases and liquids
through pipes, consisting variably throttling the medium filling the pipe, without
interrupting its passage therethrough, (said throttling being indicated exter-
ally) by means of a valve, cock or the like, to produce a difference in pressure,
from which by taking into account the friction of the specific gravity of the
medium to be measured, the velocity may be calculated substantially as set
forth
2 An apparatus for carving out the method or process claimed in Claim 1
and consisting of a cock in the main tube, means for indicating the position
of said cock, and a manometer tube the ends of which are attached to the main
tube, in front of and behind the cock or are inserted in ports in the shell of
the cock, said ports leading from in front of and behind the plug of the cork
into the main tube
3 The method of mixing two gaseous or liquid substances, or gaseous and
liquid substances or of separating gaseous or liquid substances, or gaseous and
liquid substances into different volumes, consisting in inserting in the mixing
cr separating vessel, an adjustable apparatus, for varying the ratio of the resist-
ances in the two branch tubes in any convenient manner, and in reading off the
ratios of the media to be mixed or separated, either from the ratios of the
respective resistances, and the differences of pressure thereby produced in the
branch tubes, or from the ratios of the respective resistances alone, by equalising
the pressure in the branch tubes.

page_text: 4 An apparatus for caring out the method or process claimed in Claim 3,
consisting of a three way cock, means for indicating the positions of said cock
externally, the internal cross sections of said cock being such that while one
passage remains wide open, the ratios of flow through the other passages may be
vaned within exceedingly wide limits, and of a manometer tube the ends of which
are connected with the tubes in front of and behind the cock the respective
ratios of said tubes being controlled by adjusting said cock, substantially as
described.
5 The general arrangement and combination of parts composing the improved
apparatus for measuring the rate of flow, of liquids, steam and gases through
tubes and for mixing or delivering them in given proportious or quantities
all constructed and acting substantially as and for the purposes described with
reference to the accompanying diawings
Dated this 31st day of October 1899
BREWER & SON,
Agents for Applicant, London Leeds,
Chartered Patent Agents