Stirling Power Cooler LPC-RL - Stirling Cryogenics

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SC.1.1.1003 Stirling Power Cooler GPC gas power cooler The Gas Power Cooler (GPC) uses pressurized helium gas (typically 20 barg) as medium to transfer cold to the application. as a shield for the 20 K loop, maximizing the cooling power available to the 20 K target. The GPC is a two-stage Stirling cryogenerator which simultaneously provides refrigeration at 20 K and at 80 K by means of two separate heat exchangers. Each of them consists of a wound spiral tube and a cold gas pump. The two pumps circulate the gas in seperate loops, from the two heat exchangers in the application (where energy in injected into the medium) to the GPC (where energy in extracted from the medium). The GPC is connected to the application by two delivery and return lines ducted together in a single flexible vacuum insulated line. This offers flexibility for the positioning and installation of the GPC (up to a radius of 10 meters). In both the application and transfer lines, the 80 K loop can be used Operation of the GPC is fully automatic. It runs down to the lowest possible temperature depending on the application load. If required, the GPC can be equipped with a set-point controller that maintains a fixed temperature regardless of fluctuations in the application load. The delivery of a GPC system consistst of a two stage cryogenerator with two cold gas pumps and optional flexible connection lines. The figures mentioned below are only an indication, correct values can only be given after detailed technical discussion and optimization. GAS POWER COOLERS Capacity [W]** Power input Cooling water 20 K/80 K 20 K/80 K 30 K/80 K He gas flow [kW] [l/h@15°C] • GPC-1 75/0 50/400 90/400 Will be a result 11 750 • GPC-2 150/0 100/800 180/800 of customers 22 1.000 • GPC-4 350/0 200/1.600 360/1.600 process conditions. 45 3.500 ** simultaneously at 2nd stage ad 1st stage All specifications at nominal operating conditions. All data are subject to alteration without prior notice. Pictures are intended to present a general idea of the products. Stirling Cryogenics BV, Science Park Eindhoven 5003, 5692 EB Son, The Netherlands a company
SC.1.1.1003 Stirling Power Cooler FF forced flow liquid cooler with pump cryostat The Liquid Power Cooler - Forced Flow (LPC-FF) transfers energy generated by the customers application (i.e. HTS power cables, etc.) to the cryogenerator via a closed loop of liquid gas. The LPC‐FF consists of the Stirling cryogenerator, a pump cryostat and connecting lines. This LPC-FF type is effective for those applications where the application does not allow sufficient cooling by natural flow only. In this application sub cooled nitrogen (10 - 15 K below its boiling point) is used. Therefore the heat dissipated by the application only causes a temperature raise. As there is no boiling there will be no gas bubbles. This assures that the complete application is always fully filled with liquid, providing for optimal heat exchange. The warmed LN 2 (still sub-cooled) re-enters the LPC-FF flowing through a heat exchanger which heats up the buffer serving as a thermal mass. In the heat exchanger the LN 2 is cooled down and pumped through the application again by means of a cryogenic pump. A second volume is connected parallel to this application loop. This volume incorporates a heater to increase pressure throughout the system to ensure that the liquid remains sub-cooled. It also acts as an expansion vessel to compensate for density fluctuation. In the buffer tank liquid nitrogen will be boiling. The nitrogen boil‐off is fed to the Stirling cryogenerator through a vacuum jacketed (VJ) line where it is re-liquefied. The LN 2 flows back to the buffer through a VJ line by gravity. In order to regulate the temperature of the buffer the pressure is controlled between 0,2 bar(a) for 65K and 1 bar(a) for 77K. As the heat exchanger between the buffer tank and the application loop can be considered ideal, the temperature of the LN 2 at the exit of the heat exchanger will be the same as the LN 2 in the buffer tank. The LN 2 exit temperature of the LPC-FF is measured continuously. The cryogenerator capacity is reduced if the temperature starts to drop and vice versa. This compensates for the heat load variation of the application. The system can be equipped with the hardware and software needed to permit a “soft cool down” from ambient to its operating temperature and for initial filling and start up. Refrigeration mode is fully automatic and does not require any operator intervention to run or regulate it. Manual operation of certain valves is only needed when modes are changed or in temporary modes. The cooling capacity of the LPC-FF system will depend on several operating parameters like allowable ΔT across the application and required ΔP. These conditions and the associated pump losses result in a calculated flow through the application. The figures mentioned below are only an indication, correct values can only be given after detailed technical discussion and optimization. NITROGEN Capacity [W] Liquid gas flow Power input [kW] Cooling water 65 K 77 K and ΔP 65 K 77 K [l/h@15°C] • LPC-1 FF 500 840 Will be a 13 12 750 • LPC-2 FF 950 1700 result of 26 24 1500 • LPC-4 FF 2450 3750 customers process 53 49 3000 • LPC-8 FF 4500 7300 conditions. 106 98 6000 All specifications at nominal operating conditions. All data are subject to alteration without prior notice. Pictures are intended to present a general idea of the products. Stirling Cryogenics BV, Science Park Eindhoven 5003, 5692 EB Son, The Netherlands a company
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Stirling Power Cooler LPC-RL - Stirling Cryogenics

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