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*Actuators*
**2019**,
*8*(1),
16;
https://doi.org/10.3390/act8010016

Correction

Correction: Persoons, T.; Cressall, R.; Alimohammadi, S. Validating a Reduced-Order Model for Synthetic Jet Actuators Using CFD and Experimental Data. Actuators 2018, 7, 67

^{1}

School of Engineering, Parsons Building, Trinity College, Dublin 2, Ireland

^{2}

Department of Aerospace and Mechanical Engineering, University of Notre Dame, South Bend, IN 46556, USA

^{3}

Mechanical & Design Engineering School, Dublin Institute of Technology, Dublin 2, Ireland

^{*}

Author to whom correspondence should be addressed.

Received: 14 February 2019 / Accepted: 14 February 2019 / Published: 19 February 2019

The authors wish to make the following corrections to this paper [1] in Section 2.2, Equation (19). The authors wish to replace:

Alternatively, the following equation is an empirical fit for $\beta $ that is valid for $1<a<50$ and $k{A}_{n}^{1/2}<0.886$
with a mean error of 1.7% and a maximum error of 5.9%:

$$\beta \approx -0.34064+6.6771\times {10}^{-2}\text{}k{A}_{n}^{1/2}+1.5318\times {10}^{-4}\text{}{a}^{2}+2.7233\times {10}^{-8}\text{}{a}^{4}\phantom{\rule{0ex}{0ex}}+0.78343\mathrm{exp}\left(-1.7384\times {10}^{-2}\text{}a\right)$$

While Equation (19) is only valid for aspect ratios not exceeding 50, the value of $\beta $ from Equations (16)–(18) in the limit for infinite aspect ratio ($a\to \infty $) is zero.

with:

Alternatively, the following equation is an empirical fit for $\beta $ that is valid for any aspect ratio $a\ge 1$ and $k{A}_{n}^{1/2}<0.886$, with a mean error of 1.9% and a maximum error of 7.9% for $1<a<50$:

$$\beta \approx 0.5316\mathrm{exp}\left(-0.181\text{}{a}^{0.44}\right)-0.05247\text{}k{A}_{n}^{1/2}$$

In the limit for infinite aspect ratio ($a\to \infty $), the low-frequency approximation of $\beta $ obtained from Equations (16)–(19) is zero.

The authors would like to apologize for any inconvenience caused to the readers by these changes.

## Reference

- Persoons, T.; Cressall, R.; Alimohammadi, S. Validating a Reduced-Order Model for Synthetic Jet Actuators Using CFD and Experimental Data. Actuators
**2018**, 7, 67. [Google Scholar] [CrossRef]

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