What is the closure problem in turbulence?
Best insight from top research papers
The closure problem in turbulence refers to the challenge of dealing with the hierarchical nature of the equations that describe turbulent systems. Both moment and kinetic approaches to turbulence formulation involve equations that have unclosed terms of higher order, which creates the need for closure. Various methods have been developed to address this problem, including theoretical physics methods such as the direct-interaction approximation (DIA) and self-consistent-field theory . Another approach is data-driven modeling, which uses nonlinear models to approximate turbulent fluctuations as state-dependent stochastic forcing . Deep recurrent neural networks have also been used to develop closure models that accurately reproduce the statistical properties of turbulence . The development of closure models is an ongoing theoretical challenge with significant practical implications .
Answers from top 4 papers
More filters
| Papers (4) | Insight |
|---|---|
| The closure problem in turbulence refers to the challenge of accurately modeling the influence of unresolved scales on the coarse-grained equations, leading to the need for closure models. | |
| The closure problem in turbulence refers to the challenge of determining the values of higher-order statistical quantities based on lower-order statistical quantities, as these equations involve unclosed terms of higher order. | |
| The closure problem in turbulence refers to the challenge of accurately predicting the statistical behavior of turbulent flows using mathematical models. | |
| The closure problem in turbulence refers to the challenge of developing models that accurately represent the influence of small non-resolved scales on the dynamics of large resolved scales. |
Related Questions
What is a percent closure in migration?5 answersPercent closure in migration refers to the degree or extent of closure achieved during a migration process. It is a measure of how much of the original relationship between closures and environments can be restored properly. In the context of coronary artery fistula, surgical closure is a method used to treat the condition. In the case of muscular ventricular septal defects, a hybrid approach involving the deployment of a ventricular septal occluder is used for closure. In the geological storage of CO2, the closure and post-closure stages involve considering long-term migration scenarios and the behavior of CO2 in the storage reservoir and its geosphere. In cochlear implantation, electrode migration can occur, and the rate of migration may be influenced by factors such as concurrent radical mastoidectomy.
What is therapeutic closure and is it good for patients?4 answersTherapeutic closure is a treatment modality aimed at secondary prevention of recurrent embolism in patients with patent foramen ovale (PFO). Percutaneous PFO closure can be performed with a high success rate and has shown promising results in preventing recurrent embolic events. The procedure has been successful in a majority of patients and has a low risk of complications. PFO closure has been found to be effective in reducing the risk of ischemic stroke, transient ischemic attack (TIA), and peripheral embolism. However, randomized trials are needed to further define its therapeutic value. In the case of postinfarction ventricular septal defects (VSD), transcatheter closure has been successfully performed in selected patients, leading to survival post procedure. Vacuum assisted closure (VAC) therapy has shown high healing rates for complex wounds in the lower limbs in patients with vascular disease. Non-healed wounds after VAC therapy have been found to be predictors for amputation and death.
What is the closure principle?5 answersThe closure principle refers to the question of whether knowledge is closed under entailment. It has been a topic of debate and controversy for several decades. Different forms and variations of the closure principle exist, but the central problem remains the same. Some argue that knowledge can be expanded deductively only when the antecedent is knowledge by acquaintance or a priori knowledge, suggesting that the closure principle is plausible but limited. However, there are criticisms of closure principles of epistemic justification, with the contention that a novel closure principle of epistemic justification can address these criticisms and provide improvements over other contemporary closure principles. In a different context, the closure principle computational approach test (CPCAT) has been introduced as a statistical method to assess chemical effects on earthworm abundance in field studies, showing promising results compared to standard t test approaches. Additionally, the Gestalt closure principle is a principle of perceptual learning that explains how the human brain categorizes and comprehends visual elements by bridging missing gaps to visualize fragmented objects as a whole.
How comfortable closure in counselling?5 answersClosure in counseling is an important aspect of the therapeutic process. It signifies both an ending and a beginning, as it marks the conclusion of the present counseling relationship while also potentially establishing a foundation for future support during times of crisis or difficult life transitions. Comforting the patient and their family is a key goal of counseling, and effective communication is crucial throughout the entire treatment process. The COVID-19 pandemic has brought new challenges to mental health professionals, leading to a shift towards tele-counseling as a convenient mode of providing mental health services. In times of disasters, such as the Grenfell fire, counseling boundaries may need to be reevaluated, and the therapeutic relationship remains important for successful outcomes. Developing counseling skills can benefit individuals in various settings, including everyday life and professional contexts.
Why high temperatures and high pressures is a problem when closing a well?1 answersHigh temperatures and high pressures are a problem when closing a well because they can lead to wellbore instability and casing collapse. This is especially critical in harsh geological conditions such as deepwater exploration and high-pressure-high-temperature reservoirs. The main causes of instability are high formation pore pressure, drilling-induced disturbance of the stable formation, and possible chemical reactions between the reservoir formation and the drilling and completion fluids. Understanding and controlling blowout risks is also important in order to prevent incidents like the Deepwater Horizon oil spill. Therefore, it is necessary to develop mathematical models to simulate the physical problems that arise from drilling and production processes.
Benefits of closure band aid?5 answersA closure band aid offers several benefits. It enhances drinking and pouring by providing a closure orifice that is at least as large as the container orifice, allowing for easy opening and pivoting of the top cover. It also provides tamper resistance through a tear band that encircles the top cover and secures the lid to the base. Additionally, a closure band aid facilitates wound healing by regulating pressure on the wound, promoting compression and preventing tearing and bleeding. Another advantage is the ability to securely install a bracelet on one's own wrist without assistance, thanks to an elastic wrist band with a bracelet end holding means. Furthermore, a closure band aid can be used for closing tubular packs, with closure elements connected to form a one-piece closure element band that can be tightened and prevents detachment.