Investigation of alternative layouts for the supercritical carbon dioxide Brayton cycle for a sodium-cooled fast reactor

Numerical estimates for the bulk viscosity of ideal gases

“…The second term in (18) represents the Stockmayer correction for polar fluids; details of the latter can be found in Reid, Prausnitz, and Sherwood. 37 A further discussion of (16)- (18) and the numerical values of A i , i = 1 → 6, are found in Reid, Prausnitz, and Poling. 36 The numerical values of T and σ were taken from Appendix B of Reid, Prausnitz, and Poling 36 or Svehla's original report.…”

“…If we use the more accurate estimate (16) for the viscosity, we must include the collision integral (18) in the numerator of (36). Because = (T ) at fixed temperature and T is independent of θ v , a pure correlation of μ b /μ with θ v is not strictly possible.…”

“…Examples include the flows in Rankine cycle power systems using steam as a working fluid as well as systems which employ non-aqueous working fluids. The latter working fluids tend to be advantageous when non-fossil fuel heat sources are used; see, for example, the studies of organic Rankine cycles by Curran, 6 Devotta and Holland, 7 Yan, 8 Hung, Shai, and Wang, 9 Liu, Chien, and Wang, 10 Wei et al, 11 Saleh et al, 12 and Shuster, Karellas, and Aumann 13 or the studies of Dostal et al, 14,15 Dostal, 16 Moisseytsev, 17 Moisseytsev and Sienicki, 18 and Sarkar 19,20 on the use of CO 2 and N 2 O for nuclear power systems. Even if the working fluid is steam, our examination of the literature indicates that no estimates of the bulk viscosity are currently available for water vapor.…”

Numerical investigation on heat transfer to supercritical CO 2 in rolling motion

“…When the pressure head is relative low, the flow rate fluctuates periodically, but the flow rate is nearly invariable under relative high pressure head. For the practical application in nuclear power ship, the pressure head of supercritical CO 2 Brayton cycle outclasses the additional pressure drop induced by rolling motion (Kato et al, 2004;Moisseytsev and Sienicki, 2009), which means the relative pressure fluctuation approximates zero. Therefore the effect of rolling motion on mass flow rate fluctuation can be neglected reasonably.…”

Thermodynamic analyses and optimization of a recompression N2O Brayton power cycle

“…This leads to an increase in heat rejection rate, which thus exhibits reverse trend compared to the situation where pressure ratio is less than the optimal value. It may be noted that if either the minimum cycle temperature or pressure is specified, then an optimal value exists for the other similar to CO 2 [11]. The optimum values corresponding to maximum efficiency are obtained along with simultaneous variation of split flow fraction and the compressor pressure ratio having a step size (the difference between two consecutive values) of 0.001 and 0.001, respectively.…”