Prandtl‐Reuss model without safe‐load conditions

Abstract Toxicity of sulfite (Na2SO3) and cadmium (CdCl2) ions to anaerobic granular sludge was investigated in 1.2 litre bench-scale upflow anaerobic sludge blanket (UASB) reactors during process acclimation and shock load conditions. Minimal sulfite toxicity was observed under gradual and shock load conditions at sulfite concentrations of up to 1000 mg S/L if proper acclimation was allowed to occur. No long-term toxic effects were observed although the COD digestion rate was temporarily inhibited by shock load of sulfite. Scanning electron micrographs indicated that more sulfate-reducing bacteria were present in the granules developed in the reactors with sulfite supplement although rod-shaped Methanosaeta-like bacteria were still dominant. High bacterial growth rate was observed in the reactors which were supplied with the feed containing sulfite. The COD digestion rate was inhibited at a cadmium loading rate of 2.4 g Cd per day under both acclimation and shock load conditions. Acclimation did not seem to improve the bacteria to tolerate the toxicity of cadmium. The concentration of free cadmium was very low in the reactors under normal conditions, but increased rapidly when the COD digestion in the reactors ceased. The bacteria could not be reactivated after inhibited by cadmium. When reactors were operated at low specific COD loading rates, more inorganic precipitates were formed inside the granules which consequently settled faster.

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A substation concept for changeable load conditions

18th International Conference and Exhibition on Electricity Distribution (CIRED 2005) ◽

10.1049/cp:20050909 ◽

2005 ◽

Cited By ~ 2

Author(s):

W. Lord ◽

L. Ahnlund ◽

B. Wallbing-Lovgren ◽

A. Lundvall

Keyword(s):

Load Conditions

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Structural Effect of En-echelon Fractures on Shear Behavior of Rock Mass Under Constant Normal Load Conditions: An Experimental Study

Rock Mechanics and Rock Engineering ◽

10.1007/s00603-021-02555-3 ◽

2021 ◽

Author(s):

Yuanchao Zhang ◽

Yujing Jiang ◽

Daisuke Asahina ◽

Zhi Wang

Keyword(s):

Experimental Study ◽

Rock Mass ◽

Normal Load ◽

Shear Behavior ◽

Structural Effect ◽

Constant Normal Load ◽

Load Conditions

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Influences of Residual Stress, Surface Roughness and Peak-Load on Micro-Cracking: Sensitivity Analysis

Metals ◽

10.3390/met11020320 ◽

2021 ◽

Vol 11 (2) ◽

pp. 320

Author(s):

Jairan Nafar Dastgerdi ◽

Fariborz Sheibanian ◽

Heikki Remes ◽

Hossein Hosseini Toudeshky

Keyword(s):

Residual Stress ◽

Surface Roughness ◽

Crack Formation ◽

Peak Load ◽

Crack Size ◽

Effective Parameters ◽

Load Range ◽

Load Effect ◽

Damage Initiation ◽

Load Conditions

This paper provides further understanding of the peak load effect on micro-crack formation and residual stress relaxation. Comprehensive numerical simulations using the finite element method are applied to simultaneously take into account the effect of the surface roughness and residual stresses on the crack formation in sandblasted S690 high-strength steel surface under peak load conditions. A ductile fracture criterion is introduced for the prediction of damage initiation and evolution. This study specifically investigates the influences of compressive peak load, effective parameters on fracture locus, surface roughness, and residual stress on damage mechanism and formed crack size. The results indicate that under peak load conditions, surface roughness has a far more important influence on micro-crack formation than residual stress. Moreover, it is shown that the effect of peak load range on damage formation and crack size is significantly higher than the influence of residual stress. It is found that the crack size develops exponentially with increasing peak load magnitudes.

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