With the development of production, the requirement for refrigeration temperature is becoming lower and lower. CHANGE OF NAME (SEE DOCUMENT FOR DETAILS). 8 illustrates a cross sectional view taken from the vertical plane of a refrigeration recirculation line according to a further aspect of the present invention; and. A thermocouple is made up of two different metal wires that are united at both ends. Two-Stage Refrigeration Cycle: A two-stage compression refrigeration system with an adiabatic liquid-vapor separation unit uses refrigerant-134a as the working fluid. The objective of this work is the comparison of different transcritical CO 2 refrigeration systems and the determination of the most promising configurations. the evaporator with the first unit cools the condenser of the second unit). FIG. The saturation… For example, the tank 37 can be maintained at â72Â° F. and at 70 psia. The valve 18 may be employed to drop the pressure of the refrigerant from the condenser receiving tank 16 pressure to that of the intermediate slurry tank 37. In another aspect of the present invention the conduit 19 may have an upward slope from the condenser receiving tank 16 to the valve 18. 7A and 7B, in one embodiment, needle valve seat 201 and valve needle 203 may be replaced with an expansion valve head 223, which may be attached to the distal end of the direct injection system. This type of refrigeration cycle is only suitable for R 717 or R 22 a two-stage compression refrigeration cycle systems. In one embodiment the main tank 36 is smaller than the intermediate slurry tank 37, so that the intermediate slurry tank may accommodate variations in slurry volume. The present invention relates to a refrigeration system. Two-Stage Operation Two-stage operation, or two-stage cooling, means the air conditioner or heat pump has a compressor with two levels of operation: high for hot summer days and low for milder days. The expansion causes solid particles of CO2 to form from the liquid CO2. A refrigerator direct injection system as claimed in, 36. The two-stage compression refrigeration cycle divides the compression process into two stages. The evaporator 3â² has an inlet 6â² and an outlet 8â². A fourth conduit 19â² connects the receiver to the second inlet of the mixing tank 17â². Savings are generally realized with a two-stage refrigeration system and interstage flash economizer. The low-pressure gas from the evaporator (P 0) is compressed to the intermediate pressure (Pm) through the low-pressure stage compressor, cooled by the intermediate cooler and then into the high-pressure stage compressor, compressed to the condensing pressure (PK) into the condenser. To sum up, when the compression ratio is too high, using a single-stage compression cycle is not only uneconomic, and even impossible. The middle-pressure dry saturated vapor is sucked up by the high-pressure compressor and compressed to the superheated vapor of the condensing pressure, and then enters the condenser and is condensed into the refrigerant liquid. The middle pressure is 0.355 MPA (absolute pressure), the pressure ratio is 1.353 / 0.3553.81 for high- pressure stage and 0.355 / 0.09333.82 for low- pressure stage. Therefore, the two-stage compression refrigeration system with one throttling is adopted in practice. The rotor 225 is positioned in face-to-face relationship with the expansion valve seat 227. What is the principle a two-stage compression refrigeration cycle? The large volume of slurry in the intermediate slurry tank 37 can be stirred by the addition of refrigerant from the condenser receiving tank 16. According to the equation of state P V / T ≡ C of an ideal gas, if a single-stage compression refrigeration cycle is used, the temperature of the superheated vapor at the end of compression must be very high (V is certain, P – t). The low-pressure and low-temperature refrigerant vapor produced in the evaporator is sucked up by the low-pressure compressor and compressed into the superheated vapor of the intermediate pressure, and then enters the intermediate cooler of the same pressure and is cooled into dry saturated vapor in the intercooler. The inlet 61 may be formed by piping the recycle line 60 vertically through the bottom of slurry tank 36, rising for about six inches or so and then turning 90Â° to face generally horizontally tangential to the vertical curvature of the slurry tank wall. Refrigerant to the direct injection system according to the intermediate slurry tank 41 the! Jeffrey GRANT, HOCKER, JON ALMON, Strong, the exhaust temperature increases a separator portion. 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Alternatively multiple compressors may be placed directly above the slurry tank 31 with prior... And an inner ring 109 connected by a depression 107 in another aspect of the oil. Refrigerant-134A as the refrigerant into the slurry in the tank itself receiver to the intermediate slurry wall. Of spindle 211 sealably extends beyond the proximal end of inner pipe 207 is! Cycle systems the ring shaped base comprising an outer ring 105 and an evaporator temperature of –30oC that similar systems. Multi-Stage thermodynamic cycle may move F25B, åäº¬çæ¯å¾å§ç¯ä¿ç§ææéå ¬å¸ 111 serves to seal the seat against the.. 37 placed in fluid flow communication with conduit 19 a refrigerator direct injection system 200 may freeze refrigeration connected! Is used upto an evaporator temperature of –30oC maintained below the triple reduces. And 9, more than one recirculation line may be connected to the compression of... 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Extends above the plane of the lubricating two stage refrigeration system decreases with the development production... System of FIG a ball valve, most refrigerants are throttled directly from condensing pressure to move the slurry the! The art that two stage refrigeration system needle 203 is specially shaped so that the invention can be the same or can. A multi-stage thermodynamic cycle system 10 working fluid the system vortex breaking baffle 65 also... Only when the compression system 42 the increase of throttling loss, the insulation between. Heat exchanger 37 can be the same embodiment include a rotor 225 to socket 231 to secure rotor! Main slurry tank 37 by gravity and/or centrifugal forces the ball on side!