Fly ash, a result of coal burning in thermal power plants, is sustainably used in agriculture and has been regarded as a problematic solid waste worldwide. The presence of some desired nutrients (macro and micro) and its porosity makes it a marvelous soil amendment for plant growth and development. The present study was done to evaluate the effect of different fly ash levels on pumpkin crop (Cucurbita moschata). Pot experiment in randomized block design was conducted with different fly ash supplement treatments to analyze the impact of fly ash on growth, chlorophyll, carotenoid, biochemical parameters, and pumpkin crop yield. The results show variation in soil’s physical and chemical properties after the application of fly ash (30 and 50%). Also, the lower levels (10–30%) of fly ash amended soil significantly (P ≤ 0.05) enhanced the growth (plant height, plant fresh and dry biomass, no. of leaves, and average area of the leaf), chlorophyll content, and biochemical contents (protein, carbohydrate, mineral, and leaf water content) in pumpkin crop. The proline content was also observed to enhance by the increasing levels of fly ash to soil. The yield parameters in terms of a number of flowers and fruits, fruits’ length and diameter, and fresh and dry weight of fruits were also significantly increased in amended soil with 10–30% fly ash. On the other hand, the higher doses, i.e., 40% and 50% of fly ash showed a negative effect and reduced the growth, chlorophyll, carotenoid, biochemical content, proline, and yield in pumpkin crop. We concluded that the lower level of fly ash (up to 30%) could be used as fertilizer in agricultural fields for the improvement of vegetable as well as other food crops in a sustainable manner but the higher level of fly ash (40 and 50%) is toxic to the plant.

Impact of the low and high concentrations of fly ash amended soil on growth, physiological response, and yield of pumpkin (Cucurbita moschata Duch. Ex Poiret L.).

CFD-DEM analysis of hydraulic conveying bends: Interaction between pipe orientation and flow regime

Tribological performance of Yttrium (III) and Zirconium (IV) ceramics reinforced WC–10Co4Cr cermet powder HVOF thermally sprayed on X2CrNiMo-17-12-2 steel


 This paper presents an overview about particulate wear that occurs in various components of slurry pumps, pipeline systems, and hydraulic turbines due to the mechanical action caused by the flow of solid–liquid mixtures. Three most common wear problems, namely, erosion, erosion–corrosion, and abrasion occur in different industries like thermal and hydro power plants, mining, chemical, and marine industries. Therefore, the efficiency of these industries and power plants highly depends on the wear damages. So, it becomes necessary to govern the wear phenomenon. In this paper, the various properties of particles and target are discussed on which the particulate wear depends. Present overview explains the experimental methods of measuring the particulate wear at in situ and ex situ conditions by using the different types of testers, rigs, and pilot plant test loops. Moreover, the empirical and analytical correlations or models for the prediction of particulate wear in pumps, piping circuits, and hydraulic turbines are also discussed in present literature review. By studying the all possible advantages and disadvantages, the gaps in knowledge of wear prediction methods and models are highlighted. At the end, a “think-model” for the prediction as well as reduction of wear in the various components is presented on the basis of different experimental and computational fluid dynamics (CFD) based simulation work. Further investigations can be carried out to develop the more accurate and flexible models that can be used to predict the particulate wear in a wide range of applications.

A Review on Mechanisms and Testing of Wear in Slurry Pumps, Pipeline Circuits, and Hydraulic Turbines

In the present study, erosion wear of a 90 pipe bend has been investigated using the Computational fluid dynamics code FLUENT. Solid particles were tracked to evaluate the erosion rate along with k-ɛ turbulent model for continuous/fluid phase flow field. Spherical shaped sand particles of size 183 μm and 277 μm of density 2631 kg/m are injected from the inlet surface at velocity ranging from 0.5 to 8 ms at two different concentrations. By considering the interaction between solid-liquid, effect of velocity, particle size and concentration were studied. Erosion wear was increased exponential with velocity, particles size and concentrations. Predicted results with CFD have revealed well in agreement with experimental results. The magnitude and location of maximum erosion wear were more severe in bend rather than the straight pipe.

https://jafmonline.net/JournalArchive/download?file_ID=48989&issue_ID=256

Modeling of Erosion Wear of Sand Water Slurry Flow through Pipe Bend using CFD

In the present study, erosion wear behavior of slurry pipeline due to solid–liquid suspension in the pipeline has been investigated using commercial computational fluid dynamics (CFD) code FLUENT. A multiphase Euler–Lagrange model was adopted to predict the solid particle erosion wear in a 90° pipe bend for the flow of bottom ash–water suspension. A standard k–e turbulence modeling scheme was used to simulate the flow through the pipeline. Water and bottom ash were taken as liquid and as a dispersed phase of solid–liquid mixture, respectively. A simulation study for erosion wear in a pipe bend was carried out to investigate the influence of various parameters including velocity, solid concentration, and particle size. The velocity of the bottom ash–water suspension varied from 0.5 to 2.5 m/s for solid concentrations with a range of 2.5 to 10.0% (by volume). The particle diameters of the bottom ash were 162 and 300 µm. The simulation results agree with the results of previous studies.

Prince Kumar

Papers

CFD modeling of erosion wear in pipe bend for the flow of bottom ash suspension