Cross Flow past Circular Cylinder with Waviness in Confining Walls near the Cylinder

Two dimensional flow past circular cylinder confined by walls with local waviness near the cylinder has been studied. The aim of the present study is to identify the ability of the waviness to control vortex shedding, for which two different waviness configurations such as in-phase configurations (IPC) and out-phase configurations (OPC) are considered. Further, the effect of location of the local waviness with respect to the cylinder has also been studied. Air is the working fluid and the flow is assumed to be laminar and incompressible at Re=200. The finite volume based CFD solver Ansys Fluent (Version 15.0) is used for the computations. Flow characteristics such as drag, lift and Strouhal number are computed. Interesting shedding characteristics and drag reduction are observed due to the presence of local waviness. However, the significant factor is the location of waviness in the confining walls that leads to complete suppression of shedding. Among various locations and configurations of waviness studied, waviness in downstream with OPC3 suppresses the vortex shedding completely with reduced drag

Humanity's Last Exam

Benchmarks are important tools for tracking the rapid advancements in large language model (LLM) capabilities. However, benchmarks are not keeping pace in difficulty: LLMs now achieve over 90\% accuracy on popular benchmarks like MMLU, limiting informed measurement of state-of-the-art LLM capabilities. In response, we introduce Humanity's Last Exam (HLE), a multi-modal benchmark at the frontier of human knowledge, designed to be the final closed-ended academic benchmark of its kind with broad subject coverage. HLE consists of 3,000 questions across dozens of subjects, including mathematics, humanities, and the natural sciences. HLE is developed globally by subject-matter experts and consists of multiple-choice and short-answer questions suitable for automated grading. Each question has a known solution that is unambiguous and easily verifiable, but cannot be quickly answered via internet retrieval. State-of-the-art LLMs demonstrate low accuracy and calibration on HLE, highlighting a significant gap between current LLM capabilities and the expert human frontier on closed-ended academic questions. To inform research and policymaking upon a clear understanding of model capabilities, we publicly release HLE at https://lastexam.ai

Reproductive Phenology of Lannea coromandelica (Houtt.) Merr.

Lannea coromandelica (Houtt.) Merr. is a fast growing, large size deciduous tree which is widely used for Jhingan gum extraction, timber, ornamental and medicinal purpose. The better understanding of phenology will help us to efficient utilization of these trees in urban landscapes and agroforestry systems. The present investigation revealed that L. coromandelica was starts flowering from Mid-January to March. It has a mean of 26 flowers per inflorescence with 0.54 % fruit set and 0.80% seed set around.The fruits attain harvest maturity at 18th week after anthesis with a distinctive colour change from light red to darker red colour. Seeds are orthodox in nature and have maximum of 52.67% germination.</jats:p

Effect of rotating control cylinder location on vortex shedding behind a main cylinder

Abstract The dynamic behavior of flow over a circular main cylinder (MC) in presence of single small rotating control cylinder (CC) has been studied numerically at Reynolds number, Re = 100 and 200. The CC location (r cc = 0.6D–1D), rotational direction (clockwise and counterclockwise) and rotational rate (α = 0–2) of CC are taken as the study parameters. The flow field variables are computed using Ansys Fluent 15.0, the vortex shedding characteristics such as Strouhal number (St), drag (C D ) and lift (C L ) coefficients are analyzed. It is identified that the fluid shearing between MC and CC significantly controls the vortex formation behind the MC and subsequent vortex shedding. Unlike existing study, which reports the vortex shedding suppression only for the very closer location of CC, the present work identified new locations of CC for vortex shedding suppression. At Re = 100, suppression is identified at three different locations of CC (r cc = 0.7D, 0.9D and 1D) with lower α (α = 0.5, 1) due to a favorable pressure gradient (FPG) over MC. But with increasing Re, CC at higher r cc and lower α does not generate FPG. At Re = 200, shedding suppression is observed only at higher α (α = 2) and closer location of CC ( θ = 75 ∘ , r c c = 0.7 D ), which is identified as an optimum location based on vortex shedding suppression on the MC with reduced drag (65.45%, 75.8%) respectively for Re = 100 and 200.</jats:p