Natural Convection Heat Transfer of a Nanofluid into a Cubical Enclosure: Lattice Boltzmann Investigation

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Blasius and Sakiadis problems in nanofluids

The classical problems of forced convection boundary layer flow and heat transfer past a semi-infinite static flat plate (Blasius problem) and past a moving semi-infinite flat plate (Sakiadis problem) using nanofluids are theoretically studied. The similarity equations are solved numerically for three types of metallic or nonmetallic nanoparticles such as copper (Cu), alumina (Al2O3), and titania (TiO2) in the base fluid of water with the Prandtl number Pr = 6.2 to investigate the effect of the solid volume fraction parameter φ of the nanofluids. Also, the case of conventional or regular fluid (φ = 0) with Pr = 0.7 is considered for comparison with known results from the open literature. The comparison shows excellent agreement. The skin friction coefficient, Nusselt number, and the velocity and temperature profiles are presented and discussed in detail. It is found that the solid volume fraction affects the fluid flow and heat transfer characteristics

A Meta‐Analysis on the Effects of Text Structure Instruction on Reading Comprehension in the Upper Elementary Grades

In this meta‐analysis, the authors synthesize results from 44 (quasi‐)experimental studies on informational and narrative text structure interventions involving students in grades 4–6 in regular school settings. Findings show that text structure instruction had positive immediate effects on students’ reading comprehension but that effect sizes varied largely across outcome measures: questions (Hedges’ g = 0.25), summarization (g = 0.57), recall (g = 0.37), and knowledge about text structure (g = 0.38). However, students who received text structure instruction no longer outperformed control groups at delayed posttests. Content‐related features, such as a focus on paragraph‐level structure, active construction of graphic organizers, and teaching rule‐based summarization techniques, moderated the effectiveness of text structure instruction, but these effects also varied across outcome measures. Instructional features moderated delayed effects: Interventions with opportunities for individual student practice resulted in higher delayed effects for comprehension questions. The authors argue that text structure instruction deserves a place in the primary school curriculum so the positive effects on reading will be maintained