Design Comparison of Cesium and Potassium Vapor Turbine-Generator Units for Space Power Plants.

Fraas, A.P.; Burton, Darrin; LaVerne, M.E.; Wilson, L.V.

doi:10.2172/4837253

Cited by 6 publications

(2 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Potassium and caesium gained serious attentions and were exhaustively studied in the past. [11][12][13] In Gruntz, 14 a detailed study of a binary potassium-steam Rankine power system of 5000 kW for remote power stations, small ships, or submarines was presented. According to that study, potassium is compatible with conventional stainless steels (316 and 321 types) up to 870 C, and with cobalt alloys (like Haynes 25) up to 1090 C. For temperatures between 1000 C and 1090 C, potassium seems compatible with refractory alloys based on niobium, molybdenum, and tantalum.…”

Section: Topping Cycle Working Fluids: the Alkali Liquid Metalsmentioning

confidence: 99%

Binary liquid metal–organic Rankine cycle for small power distributed high efficiency systems

Bombarda

Invernizzi

2014

Proceedings of the Institution of Mechanical Engineers, Part A:

View full text Add to dashboard Cite

There is a common interest in the distributed power generation: generally for the combined production of electrical and thermal energy and often, although not necessarily, in association with renewable energies as heat sources for the prime mover. For example, in the field of distributed concentrated solar power generation of small size, the gas engine technology now seems to be prevailing (Stirling engines operating at maximum temperatures of 600-800 C, with peak net efficiencies at 20-30% and power up to several kilowatts are commonly considered). Organic Rankine engines, fed by biomass, in the power range of about 1 MW are actually a standard. From a strictly thermodynamic point of view, the binary cycle technology, accomplished by alkaline metal Rankine cycle as the topping cycle and a Rankine cycle with organic fluid as the bottoming cycle, could be an advantageous alternative. By their very nature, Rankine cycles have good thermodynamic qualities and, potentially, their thermodynamic performance, for the same maximum and minimum temperatures, could be better than that of a gas cycles. This paper discusses the possibility of adopting binary cycles with a power level in the order of tens of kilowatts. Following an overview of the characteristics of alkaline metals and a look at the possible organic fluids that can be employed in Rankine engines at high temperature (400 C), assuming a limit condensation pressure of 0.05 bar, the thermodynamic efficiency of binary cycles was evaluated and the preliminary sizing of turbines was discussed. The results (e.g. a net cycle efficiency of around 0.46, with maximum temperature of 800-850 C) appear encouraging, even though setting up the systems may be far from easy. For instance, there are difficulties due to the extremely high volumetric expansion ratios of bottoming cycles (400-600, an order of magnitude larger than those of the topping cycles with alkaline metals that we considered), which are moreover associated with a very low minimum pressure and elevated number of revolutions of the turbomachinery (50,000-200,000 r/min). Without doubt, the design tends to be easier as the power levels increase and the minimum condensation pressure for the bottoming cycle rises. Although the authors know of no activity in progress on binary cycles at present, the interesting prospects suggest the topic deserves further study and research.

show abstract

Section: Topping Cycle Working Fluids: the Alkali Liquid Metalsmentioning

confidence: 99%

Binary liquid metal–organic Rankine cycle for small power distributed high efficiency systems

Bombarda

Invernizzi

2014

Proceedings of the Institution of Mechanical Engineers, Part A:

View full text Add to dashboard Cite

show abstract

“…The first choice of motor is a turbine. Much experimental and theoretical work has been done on the use of potassium vapor turbines for space applications [58,59,60]. In a Rankine cycle, the working fluid partially condenses as it expands within the turbine.…”

Section: Specific Massmentioning

confidence: 99%

Guided Self Replicating Factory for Colonization of Solar System

Shubov¹

2021

Preprint

View full text Add to dashboard Cite

In this work we present the concept of guided self-replicating factory (GSFR). This factory would be established as a colony on the Moon, Mercury, Mars, or Asteroid Belt. GSFR would grow by using in situ materials in order to manufacture machines. The time it takes for GSFR to double it's mass and electric power output is called a doubling period. After about 50 doubling periods, GSFR would become a Dyson Sphere civilization, which can house 10 16 people, 10 19 tons of structure and machinery and have a gross electric power of 3•10 24 W . GSRF would contain four parts. Electric power station would generate electricity for all other parts. Material production system would gather ores or native metals and produce metals, plastic, and propellant. Material shaping and assembly system would shape metal and plastic into details. These details would be assembled into machines. These machines would be added to all four parts of GSFR. Space transportation system would use fuel manufactured in situ manufactured in situ in order to facilitate transportation of machinery and astronauts from Lower Earth Orbit (LEO) to the colony. During later stages, space transportation system would also use spaceships fully or partially manufactured from space colony material.

show abstract

The Binary Cycles

Invernizzi

2013

Closed Power Cycles

View full text Add to dashboard Cite

Design Comparison of Cesium and Potassium Vapor Turbine-Generator Units for Space Power Plants.

Cited by 6 publications

References 1 publication

Binary liquid metal–organic Rankine cycle for small power distributed high efficiency systems

Binary liquid metal–organic Rankine cycle for small power distributed high efficiency systems

Guided Self Replicating Factory for Colonization of Solar System

The Binary Cycles

Contact Info

Product

Resources

About