Numerical investigation of a centrifugal compressor with various diffuser geometries for fuel cell applications

Schödel, Markus; Menze, Marco; Seume, Jörg

doi:10.29008/etc2021-686

Cited by 5 publications

(5 citation statements)

References 1 publication

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Achieving a harmonious interaction among these components across a wide operating range necessitates the geometric optimization of individual components to encompass all specified operating points. On one hand, Schoedel et al [162] conducted a study on performance map extension (PME) through the utilization of pivoting diffuser vanes and volute redesign. This initiative resulted in the substantial extension of the operating range, notably boosting the surge margin by up to 53.8%, albeit with a noteworthy efficiency penalty of up to 4.58%.…”

Section: Innovative Applicationsmentioning

confidence: 99%

Instability Phenomena in Centrifugal Compressors and Strategies to Extend the Operating Range: A Review

Cravero,

Marsano

2024

Energies

View full text Add to dashboard Cite

Centrifugal compressors are widely used in different fields. Their design requires high performance and a wide operating range, where, at lower mass flow rates, unstable flow dynamic phenomena occur, which are extremely harmful and, at the same time, complex to fully understand. This review paper presents the main research from the last 40 years on the subject of instability in centrifugal compressors, aiming to clarify the main (sometimes contradictory) causes, classifying them according to the component in which they are triggered or the interaction between them. Importance is given to works that develop criteria for the identification of the stability limit with simplified models. The main techniques used to extend the stability limit are also presented by distinguishing between passive and active fixed-flow control methods; moreover, the main works on variable geometry techniques are reported, showing the advantages and disadvantages of their use. Finally, an overview of the innovative applications of centrifugal compressors, such as fuel cells, is presented. The aim of this review is to highlight the continued interest in this field of study and provide the tools to understand the different unstable mechanisms and techniques used to extend the operating limit.

show abstract

Section: Innovative Applicationsmentioning

confidence: 99%

Instability Phenomena in Centrifugal Compressors and Strategies to Extend the Operating Range: A Review

Cravero,

Marsano

2024

Energies

View full text Add to dashboard Cite

show abstract

“…The GCI of the polytropic efficiency at the same operating point is 0.089%. Since the Menter k-ω SST model, frequently used in the field of turbomachinery, usually overestimates flow separations, the simulations are carried out with the Menter baseline model (Menter, 1993). Finally, the following criteria are used to monitor the stability and convergence of individual operating points: RMS residuals smaller than 10 −4 , imbalances between inlet and outlet of the CFD domains smaller than 0.1%, and a negative slope of the total pressure ratio plotted against the mass flow rate at a constant speed line.…”

Section: Cfd Setupmentioning

confidence: 99%

“…which estimates the power density of a PEM fuel cell shows that the electrode potential E and, thus, the electrical output power of the fuel cell increases with the oxygen partial pressure p O2 (Kurzweil, 2013). Berning and Djilali (2003) explained that the improvement in power density with the oxygen partial pressure is less pronounced above operating pressures of 3 bar.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Experimentally validated performance improvements of a cathode air supply for PEM fuel cells

Schödel,

Nachtigal,

R. Seume

2023

European Conference on Turbomachinery Fluid Dynamics and Thermodynamics

View full text Add to dashboard Cite

This study presents first-time experimental investigations of an electric turbocharger for the fuel cell air supply with different range-extending features in the centrifugal compressor. Experiments show the potential of pivoting the diffuser vanes: The surge margin of the compressor increases by up to 44.7 percentage points. This can be used to adapt the compressor map to the operating range requirements of an automotive fuel cell. However, due to efficiency losses, the compressor power consumption increases when the fuel cell is operated at full-load. Further experiments with different leading edge angles of the diffuser vanes demonstrate that the map of the centrifugal compressor can be shifted towards lower mass flow rates even by a fixed-geometry diffuser. While the original compressor can only cover 68 percent of the total fuel cell's operating range with a surge margin of 20 percent, a compressor with adapted leading edge angles of the diffuser vanes covers over 75.7 percent. By linearly reducing the leading edge angle over the vane height, the compressor power consumption decreases over the entire operating range of the fuel cell. A reduced power consumption of up to 6.3 percent is achieved at part-load.

show abstract

“…Lück et al have analysed the system behaviour of such a turbocharger with a pseudo bond graph approach [6]. Schödel et al [7] and Menze et al [8] have discussed performance map extensions for the compressor and turbine of the same fuel cell turbocharger as studied in this paper.…”

Section: Introductionmentioning

confidence: 99%

Modelling the Condensation Phenomena within the Radial Turbine of a Fuel Cell Turbocharger

Wittmann

Lück

Bode

et al. 2021

IJTPP

View full text Add to dashboard Cite

Radial turbines used in automotive fuel cell turbochargers operate with humid air. The gas expansion in the turbine causes droplets to form, which then grow through condensation. The associated release of latent heat and decrease in the gaseous mass flow strongly influence the thermodynamics of the turbine. This study aims to investigate these phenomena. For this purpose, the classical nucleation theory and Young’s growth law are integrated into a Euler–Lagrange approach. The main advantages of this approach are the calculation of individual droplet trajectories and a full resolution of the droplet spectrum. The results indicate an onset of nucleation at the blade tip and in the tip gap, followed by nucleation over the entire blade span, depending on the humidity at the turbine inlet. With a saturated turbine inflow, condensation causes the outlet temperature to rise to almost the same level as at the inlet. In addition, condensation losses reduce the efficiency and the latent heat released by condensation leads to significant thermal throttling.

show abstract

Numerical investigation of a centrifugal compressor with various diffuser geometries for fuel cell applications

Cited by 5 publications

References 1 publication

Instability Phenomena in Centrifugal Compressors and Strategies to Extend the Operating Range: A Review

Instability Phenomena in Centrifugal Compressors and Strategies to Extend the Operating Range: A Review

Experimentally validated performance improvements of a cathode air supply for PEM fuel cells

Modelling the Condensation Phenomena within the Radial Turbine of a Fuel Cell Turbocharger

Contact Info

Product

Resources

About