SU1636663A1 - Refrigerating plant - Google Patents

Description

(21) 4601700/06

(22) 11/01/88

(46) 03/23/91. Bul № 11

(72) I.K. Savitsky, A.P. Lep Vko

and I.A. Cherkasov

(53) 621.56 (088.8)

(56) Patent of France No. 2571127, cl. F 25 At 29/00, published. 1986

(54) REFRIGERATING INSTALLATION

(57) The invention relates to refrigeration engineering, in particular, to refrigeration units with an air condenser operating year-round in a wide range of ambient air temperatures. The purpose of the invention is to increase the cooling capacity at a low ambient temperature by providing pressure and subcooling the liquid refrigerant in front of the throttle device. For this, the upper and lower parts of the battery 5 are connected by pipelines 7, 8, respectively, to the steam and oil cavities of the crankcase 1, and the battery 5 is flush with the crankcase 1. As the ambient temperature decreases, overheating of the steam increases evaporator 4, part of the refrigerant as a result of this boils out of the oil-and-refrigerant mixture, which leads to an increase in the amount of refrigerant in the circuit of the installation and, accordingly, of the liquid refrigerant to the condenser. Leniye condensing 1-yl.

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The invention relates to refrigeration engineering, R in particular to refrigeration units with an air condenser operating year-round in a wide range of ambient temperatures

The purpose of the invention is to increase the cooling capacity at low ambient temperature by providing pressure and subcooling the liquid refrigerant in front of the throttle device.

The drawing shows a diagram of the refrigeration unit,

The installation comprises a series-connected compressor 1, an air-cooled condenser 2, a throttle device of constant flow cross-section, for example, a capillary tube 3, an evaporator A, a battery 5 is made in a heat pipe 1 with a suction pipe 6 between the evaporator

4 and compressor 1. The upper and lower parts of the battery 5 are connected by pipes 7 and 8, respectively, to the steam and liquid cavities of the compressor crankcase 1. Battery

5 and the compressor crankcase J are on the same level, which ensures

filling the battery 5 with oil.

Thermal contact between the suction pipe 6 and the battery 5 can be made in various ways: by winding the suction pipe 6 on the outer surface of the battery 5j by arranging part of the suction pipe inside the battery 5S as shown in the drawing | by performing part of the suction line 6 in the form of a coil located inside the battery 5 and other known ways.

The installation works as follows.

Compressor 1 compresses the refrigerant vapor and injects it into the condenser 2, where the vapor condenses, the liquid refrigerant is throttled in the capillary tube j and enters the evaporator 4.

Since the battery 5 is connected by pipes 7 and 8 to the crankcase of the compressor 1, a certain level of oil-coolant mixture is established in it. Since the battery 5 is made in thermal contact with the suction pipe 65, the temperature

to

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20

25

35

40

45

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The ratio of the oil / cold mixture is determined by the temperature of the refrigerant vapor at the outlet of the evaporator 4. The pressure in the accumulator 5 is equal to the pressure in the crankcase of compressor 1

Thus, in the steady state, the concentration of the refrigerant in the oil-and-refrigerant mixture in the accumulator 5 is determined by the ratio between the temperature at the outlet of the evaporator 4 and the pressure in the crankcase of compressor 1, i.e. overheat value of refrigerant steam.

Since the vapor pressure of the refrigerant over the mashladon mixture at the same temperature is always less than the vapor pressure over the pure refrigerant, in the installation at steady state the superheat of the refrigerant vapor in the compressor suction is always ensured.

In the case of, - if the temperature of the oil-hollowon mixture differs from the equilibrium one, either the mixture will be saturated with freon or the refrigeon will boil out of the mixture

When the cooling air temperature decreases, the condensation pressure decreases, the refrigerant flow rate through the capillary tube 3 decreases, the boiling and suction pressure decreases, the superheat of the vapor at the outlet of the evaporator 4 increases, the equilibrium of the oil-and-freon mixture in the accumulator 5 disrupts, some refrigerant from the mixture boils away, which to an increase in the amount of refrigerant circulating in the circuit, an increase in the amount of liquid refrigerant in the condenser 2, which leads to an increase in the pressure and magnitude of the supercooling of the liquid refrigerant Before the capillary tube 3, whereby the flow of refrigerant through the capillary tube 3 increases, the boiling point increases and decreases the magnitude of the pressure superheated steam in the evaporator 4, is set a new equilibrium state of the system.

As the temperature of the cooling air increases, the condensation pressure increases, the flow rate of the refrigerant flowing through the capillary tube 3 into the evaporator & increases. boiling and suction pressure

50

55

Claims (1)

Not only does the amount of superheating of steam in the evaporator 4 decrease, the equilibrium of the mastyochondone mixture in the accumulator 5j starts to absorb chladone by the mashlahladon mixture, which leads to a decrease in the amount of chladone circulating in the circuit, the amount of liquid refrigerant in the condenser 2 decreases, due to which the condensation pressure and the degree of supercooling of the liquid refrigerant in the condenser 2 decrease, the consumption of the refrigerant through the capillary tube 3 decreases, the boiling and suction pressure decreases, the superheat increases the vapor at the outlet of the evaporator 4 establishes a new equilibrium state of the system. Invention Formula A refrigeration unit comprising a series-connected compressor, an air-cooled condenser, a throttle device of constant flow area, an evaporator, and a battery made in thermal contact with the suction pipe between the evaporator and the compressor, so as to increase the cooling capacity at low cooling air temperature by providing pressure and subcooling liquid refrigerant in front of the throttle device, the top and bottom of the battery torus connected conduits, respectively, with steam and oil crankcase cavities, wherein the accumulator is located flush with the crankcase of the compressor.