Effect of transformer operating conditions on the weight of a 375-kilowatt-electric Rankine cycle space power system
Effects of transformer operating conditions on weight of 375 kilowatt electric Rankine cycle space power system
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Effects of transformer operating conditions on weight of 375 kilowatt electric Rankine cycle space power system
Rankine cycle two loop Li boiling Ka facility for nuclear turboplant simulation, studying alkali metal corrosion for operation with and without hot traps
Metal corrosion effects in Rankine cycle lithium-boiling potassium test loop simulating working fluids of spacecraft nuclear turboplant propulsion system
Performance and transient testing of single tube potassium boiler for Rankine nuclear power plant system
Fluidic controls for automotive engine examined by Rankine cycle performance with water, CP-34, and freon TF and investigation for boiler and feed pump control criteria
Helical induction boiler feed electromagnetic pump design, fabrication and testing for potassium Rankine cycle space power system
Unalloyed tantalum as containment material in mercury Rankine cycle SNAP 8 system boiler for 5 year service life
Rankine cycle turboelectric nuclear space power conversion system with liquid K as working fluid, discussing current technology status
Condensate removal devices for potassium vapor Rankine space power turbines to prevent blade erosion and efficiency degradation
Component performance of three loop Rankine cycle test rig using lithium, potassium and NaK-78 as working fluids
The Rankine-Hugoniot (R-H) equations for hydromagnetic shocks are extended to take into consideration the energy flux and momentum flux due to waves and/or turbulence and/or heat flow in the vicinity of shocks. Eighteen shocks obseved in space were analyzed. It is found that, in order to satisfy the R-H relations with the values of measured parameters in space, waves and/or turbulence and/or heat flow are needed for the shocks with a Mach number of greater than 2, and no waves and/or turbulence are needed to satisfy the R-H equations for the shocks with a Mach number of less than 2. A discussion of the waves, turbulence, and heat flow is given. Fluctuations may considerably affect the time-averaged R-H relations.
A large portion of the materials technology is summarized that was generated in support of the development of a mercury-rankine space power system (SNAP-8). The primary areas of investigation are: (1) the compatibility of various construction materials with the liquid metals mercury and NaK, (2) the mechanical properties of unalloyed tantalum, and (3) the development of refractory metal/austenitic stainless steel tubing and transition joints. The primary results, conclusions, and state of technology at the completion of this effort for each of these areas are summarized. Results of possible significance to other applications are highlighted.
A structurally integrated vapor chamber fin (heat pipe) radiator is defined and evaluated as a potential candidate for rejecting waste heat from the potassium Rankine cycle powerplant. Several vapor chamber fin geometries, using stainless steel construction, are evaluated and an optimum is selected. A comparison is made with an operationally equivalent conduction fin radiator. Both radiators employ NaK-78 in the primary coolant loop. In addition, the Vapor Chamber Fin (VCF) radiator utilizes sodium in the vapor chambers. Preliminary designs are developed for the conduction fin and VCF concepts. Performance tests on a single vapor chamber were conducted to verify the VCF design.
The design of a facility for testing components of an advanced Rankine cycle power system is summarized. The facility is a three-loop system in which lithium, potassium and NaK-78 are the working fluids of the primary, secondary and heat-rejection loops, respectively. Design bases and performance predictions for the major loop components, including the lithium heater and the potassium boiler, condenser and preheater, are outlined.
Conceptual advanced potassium Rankine and closed Brayton power conversion cycles offer the potential for improved efficiency over steam systems through higher operating temperatures. However, for utility service of at least 100,000 hours, materials technology advances will be needed for such high temperature systems. Improved alloys and surface protection must be developed and demonstrated to resist coal combustion gases as well as potassium corrosion or helium surface degradation at high temperatures. Extensions in fabrication technology are necessary to produce large components of high temperature alloys. Long time property data must be obtained under environments of interest to assure high component reliability.
Conceptual advanced potassium Rankine and closed Brayton power conversion cycles offer the potential for improved efficiency over steam systems through higher operating temperatures. However, for utility service of at least 100,000 hours, materials technology advances will be needed for such high temperature systems. Improved alloys and surface protection must be developed and demonstrated to resist coal combustion gases as well as potassium corrosion or helium surface degradation at high temperatures. Extensions in fabrication technology are necessary to produce large components of high temperature alloys. Long-time property data must be obtained under environments of interest to assure high component reliability.
Results are given of a program whose objective was to determine the performance of refractory metal alloys in a two loop Rankine test system. The test system consisted of a circulating lithium circuit heated to 1230 C maximum transferring heat to a boiling potassium circuit with a 1170 C superheated vapor temperature. The results demonstrate the suitability of the selected refractory alloys to perform from a chemical compatibility standpoint.
Adding a metal vapor Rankine topper to a steam cycle was studied as a way to increase the mean temperature at which heat is added to the cycle to raise the efficiency of an electric power plant. Potassium and cesium topping fluids were considered. Pressurized fluidized bed or pressurized (with an integrated low-Btu gasifier) boilers were assumed. Included in the cycles was a pressurizing gas turbine with its associated recuperator, and a gas economizer and feedwater heater. One of the ternary systems studied shows plant efficiency of 42.3% with a plant capitalization of $66.7/kW and a cost of electricity of 8.19 mills/MJ (29.5 mills/kWh).