Refrigeration inventory control

Claim 2

A process for measuring and controlling refrigerant inventory in a multicomponent refrigeration cycle comprising: a. sensing the temperature, pressure, and percentage composition of a refrigerant at points in the cycle where said refrigerant is in the gaseous phase; b. computing the total amount of refrigerant inventory from said sensed temperature and pressure and an average compressibility factor, the known amount of refrigerant in the liquid phase; and c. adjusting the amount of refrigerant in said cycle as a function of the variation between a set value for total refrigerant in the cycle and the amount computed in step (b) and with reference to the percentage composition determined in step (a).

Claim 3

The process of claim 1 wherein the step of adjusting the amount of the refrigerant comprises manually controlling flow into a line communicating between a source of refrigerant makeup and the closed cycle, when the total computed amount of refrigerant is more than said set value.

Claim 4

The process of claim 1 wherein the step of adjusting the amount of refrigerant in said cycle comprises manually controlling flow from an exhaust line communicating with said closed cycle when the total computed amount of refrigerant is less than said set value.

Claim 5

A process for controlling refrigerant inventory in a multicomponent refrigeration cycle comprising: a. sensing the temperature, pressure and percentage composition of the gaseous phase of the said multicomponent refrigerant at points in the cycle where said multicomponent refrigerant is held in a constant volume; b. computing the total amount of each of said components from the information obtained in step (a); and c. adjusting the amount of each of said components as a function of the variation of said component between a set value ad the amount computed in step (b) above.

Claim 6

A process for controlling refrigerant inventory in a multicomponent refrigeration cycle comprising: a. sensing the temperature, pressure and percentage composition of the gaseous phase of the said multicomponent refrigerant at points in the cycle where said multicomponent refrigerant is held in a constant volume; b. computing the total amount of each of said components from the information obtained in step (a); and c. adjusting the amount of each of said components as a function of the variation of said component between a set value ad the amount computed in step (b) above.

Claim 7

The process of claim 4 wherein the step of computing the total amount of each component comprises; a. determining the total mass of said multicomponent refrigerant in the gaseous phase in each of said points at which the temperature, pressure and composition of the refrigerant in the gaseous phase has been sensed; b. determining the total mass of each of said components of said multicomponent refrigerant in each of said sensing points by apportioning the total mass calculated in step (a) in proportion to the percentage of each component of said multicomponent refrigerant at each of said sensed points; c. adding the mass of each component in the vapor phase at all of said sensing points to yield a gaseous phase total for each component of said multicomponent refrigerant; and d. adding to the totals calculated in step (c) the mass of each of said components of said multicomponent refrigerant in the liquid phase at each of said sensing points, whereby the total mass of each component of said multicomponent refrigerant is determined.

Claim 8

The process of claim 4 wherein the step of adjusting the amount of each component of said refrigerant comprises; a. comparing the total amount of each component computed with the preset range for that component; b. generating a signal to admit additional amounts of said component if the value computed is less than the lower limit of said preset range; c. discontinuing said signal when the amount of said component in the system reaches a level within the preset range.

Claim 9

The process of claim 6 wherein the step of adjusting the amount of each component of said refrigerant is further characterized by the steps comprising; a. generating a signal to release refrigerant from a point in said cycle where said refrigerant is rich in a component which is computed to be above the preset range for said component; b. discontinuing said signal when the total measured amount of said component reaches a level within the preset range.

Claim 10

The process of claim 5 wherein the amount of each of said components of said multicomponent refrigerants in the liquid phase is determined on the basis of controlled fixed liquid levels in each of said sensing points.

Claim 11

The process of claim 5 wherein the amount of each of said components of said multicomponent refrigerant in the liquid phase is determined on the basis of measured variable liquid levels in each of said sensing points.

Claim 12

In a closed refrigeration cycle apparatus comprising a refrigerant flowing across at least one compressor with at least one suction holdup volume upstream and at least one discharge holdup volume downstream of each compressor, said cycle characterized by at least one flash valve and at least one heat exchange stage downstream of said valve, said valve and said stage disposed between said discharge holdup volume and said suction holdup volume, the improvement comprising means for sensing the temperature, pressure, and composition of said refrigerant in the gaseous phase in each of said suction holdup volumes and said discharge holdup volumes, means for communicating said sensed temperature, pressure and composition, means for computing the amount of refrigerant in each of said volumes from said temperature, pressure and composition data transmitted to said computer means by said communicating means, and means responsive to said computer means for adjusting the amount of refrigerant in said apparatus.

Claim 13

In a closed refrigeration cycle apparatus comprising a refrigerant flowing across at least one compressor with at least one suction holdup volume upstream and at least one discharge holdup volume downstream of each compressor, said cycle characterized by at least one flash valve and at least one heat exchange stage downstream of said valve, said valve and said stage disposed between said discharge holdup volume and said suction holdup volume, the improvement comprising means for sensing the temperature, pressure, and composition of said refrigerant in the gaseous phase in each of said suction holdup volumes and said discharge holdup volumes, means for communicating said sensed temperature, pressure and composition, means for computing the amount of refrigerant in each of said volumes from said temperature, pressure and composition data transmitted to said computer means by said communicating means, and means responsive to said computer means for adjusting the amount of refrigerant in said apparatus.

Claim 14

The improved apparatus of claim 10 wherein said sensing means comprises a thermocouple, a pressure transducer, and a chromatograph for sensing the temperature, pressure and composition, respectively, of said multicomponent refrigerant.

Claim 15

The improved apparatus of claim 10 wherein said transmitting means comprises electrical conduits communicating said sensed data from said sensing means to said computing means.

Claim 16

The improved apparatus of claim 10 wherein said transmitting means comprises pneumatic conduits communicating said sensed data from said sensing means to said computing means.

Claim 17

The improved apparatus of claim 10 wherein said means responsive to said computing means comprises a recorder means for recording the mass of said multicomponent refrigerant in said cycle, and manual means for changing the amount of refrigerant in said system so that said amount of refrigerant is adjusted within a preset range.

Claim 18

The improved apparatus of claim 10 wherein said means responsive to said computer means comprises a controller means which controls flow through at least one control valve, said valve disposed in an inlet conduit communicating between a supply of a single component of said multicomponent refrigerant and said closed cycle, whereby said controller means opens said valve in said conduit communicating between a single component and said closed system when said computer means indicates a shortage of said component.

Claim 19

The improved apparatus of claim 10 wherein said means responsive to said computer means comprises a controller means which controls flow through at least one control valve, said control valve disposed in an exhaust conduit communicating between said closed cycle and a point outside said cycle, whereby said controller means opens at least one of said control valves when said computer means indicates an excess of refrigerant.