A THEORETICAL REAL-GAS ANALYSIS OF THE EXPANSION TUNNEL

Author(s):  
Glenn D. Norfleet ◽  
F. C. Loper
Author(s):  
A Guha

The influence of various levels of mathematical modelling on gas turbine performance is systematically analysed. It is shown that internal combustion with real gas effects gives rise to an optimum turbine entry temperature which does not arise in a perfect gas analysis and has not been described previously in the literature. At any pressure ratio, the maximum possible efficiency with real gas effects is significantly lower (15-20 per cent) than the maximum possible value predicted by a perfect gas analysis. An explicit equation has been derived for determining the optimum pressure ratio as a function of turbine entry temperature and component efficiencies. It is shown that the optimum design depends very strongly on turbine and compressor efficiencies. It is demonstrated that the optimum relation between pressure ratio and turbine entry temperature depends strongly on whether the optimization is carried out at fixed pressure ratios or at fixed temperatures. All previous references seem to have considered only the latter method.


2014 ◽  
Vol 39 (16) ◽  
pp. 8495-8509 ◽  
Author(s):  
Michael Striednig ◽  
Stefan Brandstätter ◽  
Markus Sartory ◽  
Manfred Klell

1912 ◽  
Vol 74 (1914supp) ◽  
pp. 159-160
Author(s):  
Lawford H. Fry
Keyword(s):  
Flue Gas ◽  

1979 ◽  
Vol 40 (C7) ◽  
pp. C7-677-C7-678
Author(s):  
S. W. Temko ◽  
K. W. Temko ◽  
S. K. Kuzmin
Keyword(s):  
Real Gas ◽  

2014 ◽  
Vol 17 (3) ◽  
pp. 154 ◽  
Author(s):  
Arıtürk Cem ◽  
Ustalar Serpil ◽  
Toraman Fevzi ◽  
Ökten Murat ◽  
Güllü Ümit ◽  
...  

<p><strong>Introduction:</strong> Clear guidelines for red cell transfusion during cardiac surgery have not yet been established. The current focus on blood conservation during cardiac surgery has increased the urgency to determine the minimum safe hematocrit for these patients. The aim of this study was to determine whether monitoring of cerebral regional oxygen saturation (rSO<sub>2</sub>) via near-infrared spectrometry (NIRS) is effective for assessing the cerebral effects of severe dilutional anemia during elective coronary arterial bypass graft surgery (CABG).</p><p><strong>Methods:</strong> The prospective observational study involved patients who underwent cerebral rSO<sub>2</sub> monitoring by NIRS during elective isolated first-time CABG: an anemic group (<em>N</em>=15) (minimum Hemoglobin (Hb) N=15) (Hb &gt;8 g/dL during CPB). Mean arterial pressure (MAP), pump blood flow, blood lactate level, pCO<sub>2</sub>, pO<sub>2</sub> at five time points and cross-clamp time, extracorporeal circulation time were recorded for each patient. Group results statistically were compared.</p><p><strong>Results:</strong> The anemic group had significantly lower mean preoperative Hb than the control group (10.3 mg/dL versus 14.2 mg/dL; <em>P</em> = .001). The lowest Hb levels were observed in the hypothermic period of CPB in the anemic group. None of the controls exhibited a &gt;20% decrease in cerebral rSO<sub>2</sub>. Eleven (73.3%) of the anemic patients required an increase in pump blood flow to raise their cerebral rSO<sub>2</sub>.</p><p><strong>Conclusions:</strong> In this study, the changes in cerebral rSO<sub>2</sub> in the patients with low Hb were within acceptable limits, and this was in concordance with the blood lactate levels and blood-gas analysis. It can be suggested that NIRS monitoring of cerebral rSO<sub>2</sub> can assist in decision making related to blood transfusion and dilutional anemia during CPB.</p>


Author(s):  
G.G. Khubulava ◽  
A.B. Naumov ◽  
S.P. Marchenko ◽  
O.Yu. Chupaeva ◽  
A.A. Seliverstova ◽  
...  

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