Correction: Reiswich et al. Effect of Flexible Flaps on Lift and Drag of Laminar Profile Flow. Energies 2020, 13, 1077

The authors wish to make the following corrections to their paper [1]:

In the introduction on page 2 and 3, we would like to add information from two additional literature sources [2,3], the reference number will be also updated accordingly. The additional text is as follows: “Kamps et al. [13] and Talboys et al. [14,15] investigated elastic flaps on the downstream side of a cylinder and airfoil in cross flow. Compared to profiles without flaps, they were able to reduce noise. This effect may have potential on small wind turbines in order to reduce sound emissions. In addition to the noise reduction, Talboys and Brücker [14] reported, in their study, on the shear layer stabilization effect that is caused by the trailing flaps on the suction side of the airfoil. This effect could also lead to enhanced airfoil performance”.

Due to the additional two sources [2,3], the table on page 3 needs to be updated from:

Table 1. Summary of the literature review with investigated profiles, Reynolds number Re of the flow, flap material, flexibility of the flap, and length with respect to the chord length of the profile c; ${}^1$ Experimental study; ${}^2$ Numerical study; ${}^3$ Polyethylene terephthalate.

Author	Profile	Re [$\times {10}^3$]	Flap Material	Flexible	Flap Length
Arivoli and Singh [3] ${}^1$	Plate	100	Cellulose acetate	yes	0.08–0.15c
Brücker and Weidner [8] ${}^1$	NACA0020	77	Elastomer	yes	0.05–0.2c
Favier et al. [7] ${}^2$	Cylinder	0.2	n/a	no	0.2c
Hafien et al. [10] ${}^2$	NACA0012	1.4–342	n/a	yes	0.04–0.11c
Johnston et al. [6] ${}^{1,2}$	n/a	400	Polyester	no	0.2c
Kamps et al. [13] ${}^1$	Cylinder	13.5–34	Elastomer	yes	0.3c
Kernstine et al. [4] ${}^1$	NACA2412	330	Aluminum foil	yes	0.1–0.4c
Liu et al. [9] ${}^1$	NACA0012	63	Mylar	yes	0.25c
Meyer [2] ${}^1$	HQ17/41	1000	Aluminum/PET ${}^3$	no	0.084–0.2c
Rosti et al. [14] ${}^2$	NACA0020	20	n/a	yes	0.1–0.2c
Schlüter [5] ${}^1$	NACA0012
	NACA2213	30–40	Carbon fiber	no	0.17c
	NACA4412

Table 1. Summary of the literature review with investigated profiles, Reynolds number Re of the flow, flap material, flexibility of the flap, and length with respect to the chord length of the profile c; ${}^1$ Experimental study; ${}^2$ Numerical study; ${}^3$ Polyethylene terephthalate.

Author	Profile	Re [$\times {10}^3$]	Flap Material	Flexible	Flap Length
Arivoli and Singh [3] ${}^1$	Plate	100	Cellulose acetate	yes	0.08–0.15c
Brücker and Weidner [8] ${}^1$	NACA0020	77	Elastomer	yes	0.05–0.2c
Favier et al. [7] ${}^2$	Cylinder	0.2	n/a	no	0.2c
Hafien et al. [10] ${}^2$	NACA0012	1.4–342	n/a	yes	0.04–0.11c
Johnston et al. [6] ${}^{1,2}$	n/a	400	Polyester	no	0.2c
Kamps et al. [13] ${}^1$	Cylinder	13.5–34	Elastomer	yes	0.3c
Kernstine et al. [4] ${}^1$	NACA2412	330	Aluminum foil	yes	0.1–0.4c
Liu et al. [9] ${}^1$	NACA0012	63	Mylar	yes	0.25c
Meyer [2] ${}^1$	HQ17/41	1000	Aluminum/PET ${}^3$	no	0.084–0.2c
Rosti et al. [14] ${}^2$	NACA0020	20	n/a	yes	0.1–0.2c
Schlüter [5] ${}^1$	NACA0012
	NACA2213	30–40	Carbon fiber	no	0.17c
	NACA4412

to the following, corrected version:

Table 1. Summary of the literature review with investigated profiles, Reynolds number Re of the flow, flap material, flexibility of the flap, and length with respect to the chord length of the profile c; ${}^1$ Experimental study; ${}^2$ Numerical study; ${}^3$ Polyethylene terephthalate.

Author	Profile	Re [$\times {10}^3$]	Flap Material	Flexible	Flap Length
Arivoli and Singh [3] ${}^1$	Plate	100	Cellulose acetate	yes	0.08–0.15c
Brücker and Weidner [8] ${}^1$	NACA0020	77	Elastomer	yes	0.05–0.2c
Favier et al. [7] ${}^2$	Cylinder	0.2	n/a	no	0.2c
Hafien et al. [10] ${}^2$	NACA0012	1.4–342	n/a	yes	0.04–0.11c
Johnston et al. [6] ${}^{1,2}$	n/a	400	Polyester	no	0.2c
Kamps et al. [13] ${}^1$	Cylinder	13.5–34	Elastomer	yes	0.3c
Kernstine et al. [4] ${}^1$	NACA2412	330	Aluminum foil	yes	0.1–0.4c
Liu et al. [9] ${}^1$	NACA0012	63	Mylar	yes	0.25c
Meyer [2] ${}^1$	HQ17/41	1000	Aluminum/PET ${}^3$	no	0.084–0.2c
Rosti et al. [14] ${}^2$	NACA0020	20	n/a	yes	0.1–0.2c
Schlüter [5] ${}^1$	NACA0012
	NACA2213	30–40	Carbon fiber	no	0.17c
	NACA4412
Talboys et al. [14,15] ${}^1$	NACA0012	50–350	Polyester	yes	0.1c

Table 1. Summary of the literature review with investigated profiles, Reynolds number Re of the flow, flap material, flexibility of the flap, and length with respect to the chord length of the profile c; ${}^1$ Experimental study; ${}^2$ Numerical study; ${}^3$ Polyethylene terephthalate.

Author	Profile	Re [$\times {10}^3$]	Flap Material	Flexible	Flap Length
Arivoli and Singh [3] ${}^1$	Plate	100	Cellulose acetate	yes	0.08–0.15c
Brücker and Weidner [8] ${}^1$	NACA0020	77	Elastomer	yes	0.05–0.2c
Favier et al. [7] ${}^2$	Cylinder	0.2	n/a	no	0.2c
Hafien et al. [10] ${}^2$	NACA0012	1.4–342	n/a	yes	0.04–0.11c
Johnston et al. [6] ${}^{1,2}$	n/a	400	Polyester	no	0.2c
Kamps et al. [13] ${}^1$	Cylinder	13.5–34	Elastomer	yes	0.3c
Kernstine et al. [4] ${}^1$	NACA2412	330	Aluminum foil	yes	0.1–0.4c
Liu et al. [9] ${}^1$	NACA0012	63	Mylar	yes	0.25c
Meyer [2] ${}^1$	HQ17/41	1000	Aluminum/PET ${}^3$	no	0.084–0.2c
Rosti et al. [14] ${}^2$	NACA0020	20	n/a	yes	0.1–0.2c
Schlüter [5] ${}^1$	NACA0012
	NACA2213	30–40	Carbon fiber	no	0.17c
	NACA4412
Talboys et al. [14,15] ${}^1$	NACA0012	50–350	Polyester	yes	0.1c

The authors would like to update the funding and acknowledgements section from:

Funding: This research was supported by Industrielle Gemeinschaftsförderung of the AiF.

Acknowledgments: The authors would like to acknowledge the support of Johannes Burkert for the image of the white-tailed eagle.

to the following, corrected version:

Funding: The IGF project No. 6 EWBR of research association Forschungsvereinigung “Forschungsinstitut für Leder und Kunststoffbahnen gGmbH”, Meißner Ring 1–5, 09599 Freiberg was supported by AiF as part of the funding program of “Industriellen Gemeinschaftsforschung und -entwicklung (IGF)” by the Federal Ministry for Economic Affairs and Energy (BMWi) according to a decision of the German Federal Parliament—Das IGF-Vorhaben 6 EWBR der Forschungsvereinigung “Forschungsinstitut für Leder und Kunststoffbahnen gGmbH”, Meißner Ring 1–5, 09599 Freiberg wurde über die AiF im Rahmen des Programms zur Förderung der “Industriellen Gemeinschaftsforschung und -entwicklung (IGF)” vom Bundesministerium für Wirtschaft und Energie (BMWi) aufgrund eines Beschlusses des Deutschen Bundestages gefördert.

Acknowledgments: We acknowledge Johannes Burkert for the image of the white-tailed eagle. Preparatory studies were first visualizations and force measurements with arrays of flexible elastic flaps for aerodynamic flow control at the IMFD and stem from the EU-FP7 project “PEL-SKIN: A novel kind of surface coatings in aeronautics FP7-AAT-2012-RTD-L0 Grant agreement ID: 334954 (https://cordis.europa.eu/project/id/334954) (accessed on 21 September 2021)”, which was funded from 2013 to 2015. The IGF project envisaged the application of these flexible flaps for rotor-blades. The proposal, including the ideas, methodology, concepts, and writing, was jointly developed by M. Stoll (FILK), C. Bruecker (then honorary professor at TU BAF and professor at City, University of London), K. Trommer (FILK), and L. Kamps (IMFD). When the proposal was finally approved in February 2017, the aerodynamic part was transferred to R. Schwarze, the successor at the IMFD.

The authors would like to apologize for any inconvenience caused to the readers by these changes. The changes do not affect the scientific results. The manuscript will be updated, and the original will remain online on the article webpage with a reference to this Correction.