Numerical Investigation of Multistaged Tesla Valves

Thompson, Scott M.; Paudel, Basil J.; Jamal, Tausif; Walters, D. Keith

doi:10.1115/1.4026620

Cited by 65 publications

(26 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…These results confirm the high-Re irreversibility reported in previous studies, which have emphasized the circuitous route taken by reverse flows 21,22,25 . Our visualizations reveal the nature of the reverse flow instability and also the extent of mixing, which we associate with increased dissipation and resistance.…”

Section: Resultssupporting

confidence: 92%

“…This work presents systematic experimental characterizations of Nikola Tesla's fluidic valve or diode across a wide range of both steady and unsteady flow conditions. The case of steady pressure/ flow-rate considered in previous studies on Tesla-like channels provides a point of comparison to our results 13,[16][17][18][21][22][23][24]31,34,35,13 . No earlier work reports on the abrupt rise in diodicity, which likely reflects the singular values or narrow ranges in Re explored.…”

Section: Discussionmentioning

confidence: 53%

“…Previous experimental and computational visualizations for Tesla-inspired channels have confirmed the reversible and irreversible flows expected at low 39 and high Re 21,22,25 , respectively. Studies of the latter validate Tesla's picture of the reverse flows taking a circuitous path around the periodic internal structures 10 with these structures lead to amplified lateral deflections that reroute streamlines and eventually induce complete mixing.…”

Section: Discussionmentioning

confidence: 68%

See 2 more Smart Citations

Early turbulence and pulsatile flows enhance diodicity of Tesla’s macrofluidic valve

2021

View full text Add to dashboard Cite

Microfluidics has enabled a revolution in the manipulation of small volumes of fluids. Controlling flows at larger scales and faster rates, or macrofluidics, has broad applications but involves the unique complexities of inertial flow physics. We show how such effects are exploited in a device proposed by Nikola Tesla that acts as a diode or valve whose asymmetric internal geometry leads to direction-dependent fluidic resistance. Systematic tests for steady forcing conditions reveal that diodicity turns on abruptly at Reynolds number $${\rm{Re}}\approx 200$$ Re ≈ 200 and is accompanied by nonlinear pressure-flux scaling and flow instabilities, suggesting a laminar-to-turbulent transition that is triggered at unusually low $${\rm{Re}}$$ Re . To assess performance for unsteady forcing, we devise a circuit that functions as an AC-to-DC converter, rectifier, or pump in which diodes transform imposed oscillations into directed flow. Our results confirm Tesla’s conjecture that diodic performance is boosted for pulsatile flows. The connections between diodicity, early turbulence and pulsatility uncovered here can inform applications in fluidic mixing and pumping.

show abstract

Section: Resultssupporting

confidence: 92%

Section: Discussionmentioning

confidence: 53%

Section: Discussionmentioning

confidence: 68%

See 1 more Smart Citation

Early turbulence and pulsatile flows enhance diodicity of Tesla’s macrofluidic valve

2021

View full text Add to dashboard Cite

show abstract

“…The aim was to find the appropriate turbulent model which agrees the best with experimental data and to optimize the valve using the right model so as to increase the diodicity. Further, Thompson et al [25] have done numerical analysis of multi-staged TV and found that the diodicity can increase up to 2 on having a series of TVs. This effect is prominent at higher Reynolds number.…”

Section: Nu=02702 Re 04713 (2)mentioning

confidence: 99%

Stability Improvement in Natural Circulation Loop using Tesla Valve – An Experimental Investigation

Arunachala

Rajat

Shah³

et al. 2019

IJMPERD

View full text Add to dashboard Cite

Natural circulation loop works on the basic principle of thermosiphon effect, which doesn't require any external force to drive the fluid in a loop. Hence they are highly applicable in power industries where there are a source and a sink. However, the flow pattern in a single-phase natural circulation loop is quite unstable especially the horizontal heater horizontal cooler configuration which results in lower loop effectiveness. A lot of research has been carried out to study these instabilities and find a way to curb them. Techniques such as tilting of loop, use of nanofluids, adding flow resistances etc. have shown promising results. But they have their own practical constraints. Hence in the present experimental study, a Tesla-type passive valve is incorporated in natural circulation loop. Due to its presence, not only stability period is reduced (at least 90 s compared to non-Tesla loop) but also unidirectional flow is achieved. The Tesla valve performed better for a broad range of heater power (90-170W) and was also able to provide noticeable resistance to the flow when the loop was inclined by 2.5° in the opposite direction.

show abstract

“…Mohammadzadeh et al (2013) showed that the best number of valve stages is two stages and explained the defect of Tesla-type valves in low-Reynolds regimes. Thompson and Paudel (2014) investigated numerically a multistage Tesla valve.…”

Section: Introductionmentioning

confidence: 99%

Performance Improvement and Two-Phase Flow Study of a Piezoelectric Micropump with Tesla Nozzle-Diffuser Microvalves

Derakhshan¹,

Beigzadeh²,

Rashidi³

et al. 2019

JAFM

View full text Add to dashboard Cite

The Present article aims to design a piezoelectric micropump using a combinational form of microvalves with sufficient diodicity in low-pressure gradients. The goal is to enhance the capability of piezoelectric micropumps with Tesla-type valves in order to deliver insulin. Tesla-type valves are in the category of passive valves which have sufficient diodicity in case of high-pressure gradients. However, low mass flow rates are often required in drug delivery devices. In this paper, the performance of MT135 Tesla-type valve in low pressure-gradient flows has been investigated and a range of reunion angles, which have not been studied before has been examined by numerical solutions. Inspired by nozzle-diffuser valve types, some changes in the bypass path of the microvalve have been exerted to boost the diodicity of the valve in low-pressure conditions that resulted in 9.97% increase of diodicity. At last but not least, the velocity gradients in singlephase flow of water has been attained and performance of micropump toward other kinds of flows has been investigated by a volume of fluid (VOF) model including water as the primary phase and air as the secondary one. To complete the analysis, a VOF model consisting of an arbitrary kind of Casson fluid with the primary phase of water was reached and discussed.

show abstract

Numerical Investigation of Multistaged Tesla Valves

Cited by 65 publications

References 9 publications

Early turbulence and pulsatile flows enhance diodicity of Tesla’s macrofluidic valve

Early turbulence and pulsatile flows enhance diodicity of Tesla’s macrofluidic valve

Stability Improvement in Natural Circulation Loop using Tesla Valve – An Experimental Investigation

Performance Improvement and Two-Phase Flow Study of a Piezoelectric Micropump with Tesla Nozzle-Diffuser Microvalves

Contact Info

Product

Resources

About