WO2014096875A1

WO2014096875A1 - Method and apparatus for measuring the volume of space and objects

Info

Publication number: WO2014096875A1
Application number: PCT/GR2013/000063
Authority: WO
Inventors: Anastasios KALLITSIS
Original assignee: Kallitsis Anastasios
Priority date: 2012-12-18
Filing date: 2013-12-18
Publication date: 2014-06-26

Abstract

The invention refers to a method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws, characterized by repeatedly changing appropriately the pressure or the volume of the gases in a space to be measured (which is sealed) by inserting or removing a known quantity of a gas or of a liquid and measuring the pressure and the temperature in order to calculate the volume thereof by the use of the constitutive equation of gases. The invention also refers to an apparatus which is appropriate for the application of the method.

Description

METHOD AND APPARATUS FOR MEASURING THE VOLUME OF SPACE AND OBJECTS

Description

The invention refers to a method and apparatus for measuring the volume of a material, an object and a space. The apparatus appropriate for the application of the method, according to the invention, is inter alia equipped with measuring devices for the gas pressure, the gas volume, the volume of the liquids and the temperature of gases and liquids. The apparatus is adaptable to a chamber for the measuring of the volume of objects. The apparatus is also adaptable to each space which has to be measured.

State of the art

Until today, the measuring of the volume of an object and a space is possible with the use of known geometrical formulas under the condition that the object or space has a normal and usual geometrical shape (for instance a cylinder, cone, cube, etc.). Furthermore, it is possible to measure the volume of an object by immersing it into a liquid, which liquid is in calibrated tanks, recording the change of the measuring indication.

There are serious disadvantages, however, in both methods. The first method requires standard geometrical shapes, which significantly restricts the application range of the method.

The second method requires the possibility of immersion and therefore the wetting of the objects to be measured. This is in many cases impossible, but, when possible, it is time consuming and requires difficult processes.

The present invention aims to ameliorate the problems of the state of the art with a method according to the characteristics of claim 1 and an apparatus according to the characteristics of claim 8. The present invention enables the measuring of the volume of bodies and spaces regardless of their shape and consistency and regardless of the state of matter (solid, liquid, gas), without calculating using geometrical formulas and without wetting the objects to be measured.

The method according to the invention is simple, inexpensive, fast and provides accuracy during measuring.

Reference is being made to the Greek Patent No 1008040 of the same inventor, which is being incorporated herein by reference.

Summary of the Invention

The present invention refers to a method of measuring the volume of a space, of objects or materials (in solid, liquid or gaseous state) by application of the gas laws. This method is characterized by repeatedly changing appropriately the pressure or the volume of the gases in the space to be measured (which is sealed) by inserting or removing a known quantity of a gas or of a liquid and by measuring the pressure and the temperature, in order to calculate the volume with the use of the constitutive equation of gases.

Brief Description of the Drawing

The Figure shows an apparatus which is appropriate for the application of the method according to the invention. The apparatus is equipped, apart from the necessary instruments, with pumps, a flow-meter, a chamber-plunger of premeasured volume in selected positions and a tank for the constant supply of the liquid.

List of Reference Numerals

1. Supporting frame

2. Manometer for the chamber or the space

3. Thermometer for the chamber or the space ygrometer for the chamber or the space xpansion valve eceiving-processing of data and displaying of the results hamber-plunger of premeasured volume in each selected position . lunger of the chamber elected positions elector of position anometer of the chamber-plunger 7 hermometer of the chamber-plunger 7 onnection pipe to the pump pout of pipe 13 onnection pipe to the pump pout of pipe 15 Flow meter for gases Thermometer Pipe for the communication between the device and the chamber or the space Tank for the constant liquid supply Pipe for the outflow of the tank with a constant liquid supply Spout for the outflow of pipe 21 Description of the Invention

3 modes of operation of the invention are described below with the aid of the attached figure:

FIRST MODE OF OPERATION: The apparatus is adapted through the pipe for the communication 19 to a chamber or a space, of any shape and size, which is sealable and has an orifice or a door or we construct an orifice or a door which is also sealable. The apparatus is equipped with a mechanical device or a vessel under pressure, which inserts or removes air (or gas) under pressure (entering or exiting the chamber) from the chamber or in the space through the spout 16 of the pipe 15. To the pipe 15 are connected a flow meter for gases 17 and a thermometer 18, which provide measurements for the volume and the temperature of the air which flows through the pipe 15. To the device are also connected a manometer 2 and a thermometer 3, which provide measurements for the pressure and the temperature inside the chamber before and after the insertion or extraction of air or gas. In this way, it is possible to calculate the volume of the chamber by the change of the pressure and temperature inside the chamber after the insertion of a quantity of air, which is measured by flow meter 17 through the equation of the gas laws. The receiving and processing of the data takes place in processor 6. SECOND MODE OF OPERATION: The apparatus is adapted through the pipe for the communication 19 to a chamber or a space, of any shape and size, which is sealable and has an orifice or a door or we construct an orifice or a door which is also sealable. The apparatus is equipped with a mechanical device or a vessel under pressure, which inserts or removes air (or gas) under pressure from the variable chamber-plunger 7 of premeasured volume, which is equipped with a manometer 11 and a thermometer 12. Thus, the quantity of air or gas inside the variable chamber-plunger 7 of premeasured volume is known. Subsequently, the variable chamber-plunger of premeasured volume 7 is connected to the chamber to be measured through the pipe 19, inserting or extracting a known quantity of air from the chamber to be measured. From the change of the pressure and the temperature in the chamber and in the variable chamber-plunger of premeasured volume 7, after the insertion or extraction of a known quantity of air, it is possible to calculate the volume of the chamber by the use of the gas laws.

THIRD MODE OF OPERATION: The apparatus is adapted through the pipe for the communication 19 to a chamber or a space, of any shape and size, which is sealable and has an orifice or a door or we construct an orifice or a door which is also sealable. The apparatus is equipped with a tank 20 with a constant supply of a liquid in the chamber. Thus, by timing the outflow of the liquid from the spout 22 into the chamber to be measured, the volume of the liquid entering the chamber is calculated. Consequently, the available volume of the chamber is decreasing by the volume of the liquid which enters the chamber through outflow 22. Thus, by the change of pressure and temperature in the chamber after inserting a known quantity of a liquid, it is possible to calculate the volume of the chamber by using the equations of the gas laws.

It is obvious that these three modes operate both individually and combined to each other.

One of many calculating approaches is the following:

In the beginning, the chamber is empty (the objects to be measured are outside the chamber), with pressure Po and volume Vo. The air inside the chamber has pressure Po, volume Veto and temperature Τθο. Subsequently, and with the door of the chamber closed, a quantity of air or gas with a volume V1 (measured in a pressure Pa1) and a temperature T01 , is inserted (or sucked out) through pipe 19, achieving pressure P1 and temperature ΤΘ1 inside the chamber. Subsequently, and after the expansion of pressure P1 through the expansion valve, the door opens and the object/objects to be measured with a volume Vx is/are inserted into the chamber and the door closes again. The available volume Vo^' of the chamber is now

Vo^'=Vo-Vx (equation 1) and inside the chamber, the air has a pressure Po^', a volume Vao^' and a temperature Τθο^'. Subsequently, and with the door of the chamber closed, a quantity of air or gas with a volume V2 (measured in a pressure Pa2) and a temperature T02 is inserted (or sucked out), achieving a pressure P2 and a temperature ΤΘ2 inside the chamber. The volume Vx can be the known volume of the liquid which flows out of the spout 22 of the tank of a constant supply 20. In this case, we can use this volume to calculate the other unknowns. The gas laws (which apply to the ideal gases, but also with an appropriate approach for the real gases) provide us with the equations.

Vo^'=Vo-Vx (equation 1)

Number of moles of air in Vao of the empty chamber:

_ V o* P o

^{K 1 00} (equation 2) where

R: is the gas constant

Number of moles of air in Vao^' of chamber with object inside: n ao =

^R * ^T6>° ^' (equation 3)

Number of moles of volume of inserted or extracted air V1

V I * P a l

^R *^{T o X} (equation 4) Number of moles of volume of inserted or extracted air V2

₂_ V2*Pa2

R*To2 (equation 5) From the constitutional equation:

PrVo = (nao+n1)*R*T61 (equation 6) P2^*Vo'= (nao^'+n2)*R^*T92 (equation 7) From the equations 1,2,3,4,5,6,7:

V V\* Ρα\*Τθο*ΤΘ\

°~ (P 1 *Τθο- Pa 1 * ΤΘ1 )* To 1 _{(equation 8)}

Vo- V2*Pa2*T0o ^'*ΤΘ2

°^' (Ρ2*Τθο ^'-Ρα2*ΤΘ2)*Το2 _(eqUation 9)

From (equation 1) Vo^'=Vo-Vx and consequently Vx=Vo-Vo^' (equation 10) From the above equations: P I

(nao+ n\ )

_(equatj_on 11)

Thus, from equations 8, 9, 10 or 11 , it is possible to calculate the volume of a chamber or of a space or of objects inserted into them. In the case in which the spaces are not completely sealed, it is possible to calculate the volume with appropriate calculations from the rate of the change of the pressure P in the chamber and the volume V of the air which is inserted or sucked out. In this case, air or gas is inserted in or sucked out (inserted or extracted from the chamber) from the chamber or the space with the apparatus, monitoring the rate of change of P, V. By continuously increasing the supply of the inserted or sucked out air from the chamber, the pressure is changing inside the chamber, up to the point where the pressure P inside the chamber is stabilized to a certain value of the supply. At this point, the supply of air (positive or negative) provided to the chamber or the space is equal to the leaks, caused by incomplete sealing.

Consequently, at this point of equilibrium, the following equations are applicable:

Qleak=Qsupply

Q=A^*P (equation 12) where

A is a characteristic factor for each chamber or space, P is the pressure at the equilibrium point.

Consequently, Qleak=A^*P=Qsupply. (In equation 12 one can use corrective factors per case for greater accuracy). Qsupply

Therefore, ^A= and since Qsupply is known, as is the stabilized

p

pressure P, it is possible to calculate A.

Subsequently, by interrupting the supply (positive or negative), the time t, which is needed for the transition from the P of the equilibrium point to another pressure P', is measured. The amount of the air or gas leakage from the chamber or the space is:

With equations such as 1, 2, 3, 4 , 5, 6, 7, 8, 9, 10, finally:

Vo =

z* CT+ O *g**T -P"*T) where

T and T^r are the temperatures of air or gas of the chamber in the equilibrium state P and of the transition to P^' respectively.

Therefore, it is possible to calculate the volume of incompletely sealed chambers or spaces, as well as the volume of objects Vx inside them, as in the case of tightly sealed chambers or spaces, with the same process, or by using the equation 10. It is obvious that the equations used in this method of the invention can differ or can be solved differently and be susceptible to corrective factors or parameters.

It is also possible to insert a chamber which is not completely sealed or has variable dimensions, under pressure, inside a bigger but sealed chamber, if both chambers are equipped with the described apparatus according to the invention. By operating the apparatuses of both chambers, it is possible to calculate the leakage of the smaller chamber, or the change of dimensions of the latter under pressure and consequently one can calculate the desired variables.

The above examples are mentioned only for the better understanding of the invention and in no way restrict the range of protection which is determined by the following claims.

Claims

1. A method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws, characterized by repeatedly changing appropriately the pressure or the volume of the gases in a space to be measured (which is sealed) by inserting or removing a known quantity of a gas or of a liquid and measuring the pressure and the temperature in order to calculate the volume thereof by the use of the constitutive equation of gases.

2. The method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to claim 1 , characterized by repeatedly changing appropriately the pressure or the volume of gases in a space of known volume (which is sealed) by inserting or removing a known quantity of a gas or of a liquid and measuring the pressure and the temperature in order to calculate the volume thereof by the use of the constitutive equation of gases through measuring, during which the objects or materials are once inside and once outside the space to be measured.

3. The method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to claim 1 , characterized by inserting or removing a gas from a space to be measured (not completely sealed) by applying an increasing supply until constant pressure is achieved inside the space, thus determining the leaks of the chamber, measuring the pressure and temperature and calculating the volume by the constitutive equation of gases.

4. The method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to claims 1 and 3, characterized by inserting or removing a gas from a space to be measured (not completely sealed) by applying an increasing supply until constant pressure is achieved inside the space, thus determining the leaks of the chamber, measuring the temperature in order to calculate the volume thereof by the use of the constitutive equation of gases through measuring, during which the objects or materials are once inside and once outside the space to be measured.

5. A method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to any of the preceding claims, characterized by inserting or removing a gas or a liquid, using a flow meter of great accuracy.

6. A method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to any of the preceding claims, characterized by using a system of a cylinder-plunger with • compartments for inserting or removing a particular quantity of gas equal to a multiple of the volume of a compartment of the cylinder.

7. A method for measuring the volume of a space, objects or materials (in solid, liquid or gaseous state) by application of the gas laws according to any of the preceding claims, characterized by using a device of constant supply during the insertion of a liquid, whose constant supply is assured by an appropriate device of selected constant cross-section of supply and constant hydrostatic pressure of a hydrostatic column with overflow at a particular height.

8. Use of the method according to claim 1 for the measuring and calibration of spaces or tanks and the measuring of materials which are inserted in or removed from these spaces or tanks.

9. An apparatus for applying the method according to claims 1 to 7, which, apart from the instruments for measuring the temperature and pressure, is equipped with a flow meter, an apparatus for the constant supply of a liquid by overflow and a standard container with compartments of variable predetermined volumes.