Abstract: Provided is an evaporator capable of, in a centrifugal chiller using a low pressure refrigerant used at a maximum pressure of less than 0.2 MPaG, preventing dry-out of a group of heat transfer pipes in an evaporator to increase heat transfer performance and to suppress reduced efficiency due to carryover of the low pressure refrigerant in a liquid phase to a turbo compressor side and a centrifugal chiller provided with same. An evaporator (7) comprises a pressure container (21) into which a refrigerant is compressed and introduced, a refrigerant inlet (22) provided on a lower portion of the pressure container, a refrigerant outlet (23) provided on an upper portion of the pressure container, a group of heat transfer pipes (25) that exchange heat with the refrigerant through the interior of the pressure container and a tabular refrigerant distribution plate (26) installed between the refrigerant inlet and the group of heat transfer pipes and in which refrigerant flow holes (26a) are drilled.

Abstract: A turbo chiller equipped with a high-efficiency two-stage turbo compressor is provided. In a turbo chiller including a control unit for controlling the degrees of opening of first inlet guide vanes of a first impeller and second inlet guide vanes of a second impeller, the control unit has a slave mode in which the second inlet guide vanes are operated so as to be dependent on the first inlet guide vanes in a slave-mode priority region, and an independent mode in which the degree of opening of the second inlet guide vanes is increased independently of the first inlet guide vanes in an independent-mode priority region.

Abstract: A turbo chiller equipped with a high-efficiency two-stage turbo compressor is provided. In a turbo chiller including a control unit for controlling the degrees of opening of first inlet guide vanes of a first impeller and second inlet guide vanes of a second impeller, the control unit has a slave mode in which the second inlet guide vanes are operated so as to be dependent on the first inlet guide vanes in a slave-mode priority region, and an independent mode in which the degree of opening of the second inlet guide vanes is increased independently of the first inlet guide vanes in an independent-mode priority region.

Abstract: A turbo chiller that can accurately determine the existence of surging occurring in a centrifugal compressor is provided. In a centrifugal compressor of a turbo chiller, which includes an impeller for compressing refrigerant, a resistance temperature sensor for detecting the refrigerant temperature is provided at the upstream side of the impeller. Accordingly, a temperature rise caused by surging can be detected and the existence of surging can be accurately determined.

Abstract: A turbo chiller that can accurately determine the existence of surging occurring in a centrifugal compressor is provided. In a centrifugal compressor of a turbo chiller, which includes an impeller for compressing refrigerant, a resistance temperature sensor for detecting the refrigerant temperature is provided at the upstream side of the impeller. Accordingly, a temperature rise caused by surging can be detected and the existence of surging can be accurately determined.

Abstract: This invention provides a condenser for a refrigerating machine which can improve the condensation characteristics by eliminating the accumulation of the condensed refrigerant in the condenser vessel. The condenser comprising the vessel 14 and a group of heat exchanger tubes 15 disposed in the vessel is used for condensing and liquefying the gaseous refrigerant by heat exchange between the gaseous refrigerant and cooling water circulating in the heat exchanger tubes. The condenser is constituted such that accumulated liquefied refrigerant is removed by forming one or a plurality of spaces in the area wherein the heat exchanger tubes are disposed.

Abstract: An evaporator is constructed such that bundles of heat exchanger tubes for flowing cold water are disposed inside a container for admitting the cooling medium. When a total cross sectional area of the heat exchanger tubes at various locations in a flow passage of the cold water is compared, the total area in a downstream location is less than a total area in an upstream location of the flow passage. Therefore, even though the temperature differential between the cold water and the cooling medium is small, the flow speeds of the cold water in the downstream tubes become faster than that in the upstream tubes, so that the heat flux is increased and heat transfer rate is improved.

Abstract: This invention provides a condenser for a refrigerating machine which can improve the condensation characteristics by eliminating the accumulation of the condensed refrigerant in the condenser vessel. The condenser comprising the vessel 14 and a group of heat exchanger tubes 15 disposed in the vessel is used for condensing and liquefying the gaseous refrigerant by heat exchange between the gaseous refrigerant and cooling water circulating in the heat exchanger tubes. The condenser is constituted such that accumulated liquefied refrigerant is removed by forming one or a plurality of spaces in the area wherein the heat exchanger tubes are disposed.

Abstract: An evaporator for a refrigerating system which prevents droplets of refrigerant from blowing upwards, and a refrigeration apparatus using thereof are provided. The evaporator for a refrigerating system includes a container into which the refrigerant is introduced, and heat exchanger tubes disposed in the container through which a cooled object flows. The evaporator further includes a prevention plate disposed above the heat exchanger tubes so that droplets of the refrigerant, which are blown upwards due to a boiling of the refrigerant, hit the prevention plate.

Abstract: An evaporator for a refrigerating system which prevents droplets of refrigerant from blowing upwards, and a refrigeration apparatus using thereof are provided. The evaporator for a refrigerating system includes a container into which the refrigerant is introduced, and heat exchanger tubes disposed in the container through which a cooled object flows. The evaporator further includes a prevention plate disposed above the heat exchanger tubes so that droplets of the refrigerant, which are blown upwards due to a boiling of the refrigerant, hit the prevention plate.

Abstract: In an evaporator composed by providing plural heat-transfer pipes for flowing cold water in a container into which a refrigerant is introduced, the heat-transfer pipes are divided into plural pipe groups and the pipe groups are arranged in a zigzag pattern with intervals between each adjacent pipe groups. Bubbles which are generated around the heat-transfer pipes provided lower position, easily come to the surface of the refrigerant, and further, there are few bubbles which degrade the performance of the heat-transfer pipes positioned around the center of the pipe groups, preventing a fall in the heat transfer coefficient.

Abstract: A condenser for condensing and liquifying a refrigerant by inducing the refrigerant into a receptacle (14), in which cooling water is fed through a plurality of thermal transmission pipes (15) which are arranged in bundles. A plate body (20) is provided between the bundles of the thermal transmission pipes, and slopes diagonally downwardly when viewed in cross-section from the direction of the length of the thermal transmission pipes. Consequently, the refrigerant falling toward the thermal transmission pipes at low positions is led diagonally downwardly by the plate body, so that the liquid film of refrigerant which adheres to the surfaces of the thertmal transmission pipes does not become too thick, thereby preventing reduction in the thermal transmittancy of the thermal transmission pipes.

Abstract: This evaporator (12) is constructed such that bundles of heat exchanger tubes (15) for flowing cold water are disposed inside the container (14) for admitting the cooling medium. When a total cross sectional area of the heat exchanger tubes (15) at various locations in the flow direction of the cold water is compared, the total area in a downstream location is less that a total area in an upstream location of the flow passage. Therefore, even though the temperature differential between the cold water and the cooling medium is small, the flow speeds of the cold water in the downstream tubes become faster than that in the upstream tubes, so that the heat flux is increased and heat transfer rate is improved even in tube group D.

Abstract: This invention provides a condenser for a refrigerating machine which can improve the condensation characteristics by eliminating the accumulation of the condensed refrigerant in the condenser vessel. The condenser comprising the vessel 14 and a group of heat exchanger tubes 15 disposed in the vessel is used for condensing and liquefying the gaseous refrigerant by heat exchange between the gaseous refrigerant and cooling water circulating in the heat exchanger tubes. The condenser is constituted such that accumulated liquefied refrigerant is removed by forming one or a plurality of spaces in the area wherein the heat exchanger tubes are disposed.

Abstract: The present invention provides a condenser for condensing and liquifying a refrigerant by inducing the refrigerant into a receptacle (14), in which cooling water is fed to through a plurality of thermal transmission pipes (15) which are arranged in bundles. A plate body (20) is provided between the bundles of the thermal transmission pipes, and slopes diagonally downward when viewed in cross-section from the direction of the length of the thermal transmission pipes. Consequently, the refrigerant falling toward the thermal transmission pipes at low positions is led diagonally downward by a the plate body, so that the liquid film of refrigerant which adheres to the surfaces of the thermal transmission pipes does not become too thick, thereby preventing reduction in the thermal transmittancy of the thermal transmission pipes.