Sensors and Actuators A 297 (2019) 111528 Contents lists available at ScienceDirect Sensors and Actuators A: Physical j ourna l h o mepage: www.elsevier.com/locate/sna Dynamic behavior of novel micro fuel pump using zinc oxide nanocomposite diaphragm R. Moradi-Dastjerdi a , S.A. Meguid a,∗ , S. Rashahmadi b a Mechanics and Aerospace Design Laboratory, University of Toronto, 5 King’s College Rd., Toronto, Ontario, Canada b Department of Mechanical Engineering, Urmia University, Urmia, Iran a r t i c l e i n f o Article history: Received 8 September 2018 Received in revised form 27 June 2019 Accepted 24 July 2019 Available online 26 July 2019 Keywords: Micro fuel delivery system Zinc oxide nanowires Piezoelectric nanocomposite diaphragm Thermo-electro-mechanical load Modeling Dynamic response Meshless method a b s t r a c t This paper is concerned with the thermo-electro-dynamic modeling of a novel micro fuel delivery system (MFDS) that is accurate, low cost and ecofriendly. To avoid the use of brittle piezoelectric materials, we propose to use a two-chamber micro-device with a bimorph piezoelectric nanocomposite diaphragm containing Zinc Oxide Nanowires (ZnO NWs). The numerical study of our dynamic model is facili- tated by mesh-free method and higher order shear deformation theory (HSDT) for varied temperatures and applied electro-mechanical loads. The elasticity modulus of the polymeric matrix is taken to be temperature-dependent. The static behavior and the natural frequency of the proposed smart nanocom- posite diaphragm are analyzed for different volume fraction of ZnO NWs, diaphragm thickness, and operating temperature. We further examined the effect of the aforementioned parameters as well as the exciting electrical potential on the delivered flowrate and backpressure of the newly proposed MFDS. The results show that the dynamic behavior of the nanocomposite piezoelectric diaphragm is governed by the volume fraction of ZnO NWs. It also demonstrates the potential use of piezoelectric ZnO NWs nanocomposite in the diaphragm of a MFDS. © 2019 Elsevier B.V. All rights reserved. 1. Introduction Micro electro-mechanical devices are extensively used to opti- mize and miniaturize the design of a large number of engineering products. The main advantages of micro-systems are apparent in many applications; including, fuel injection, fuel delivery, drug delivery, chemical analysis and cooling of microelectronic sys- tems, just to name a few. The advantages of MEMS are evident in their small size and ability to transport accurate micro-volumes of fluids [1–3]. Among the previously mentioned applications of micro-devices, MFDSs have attracted the attention of the commu- nity. This is because they are accurate, reliable, controllable and robust fuel delivery systems [4]. Micro fuel delivery systems make use of a diaphragm which is piezoelectrically excited and actuated to provide frequent but controlled change of the pressure inside a chamber to facilitate the necessary flow [5]. The design of the diaphragm and its actuation mechanism in piezoelectric-actuated micro- devices, such as the current fluid delivery system, have a significant effect on the overall performance of the devices. Consequently, current research has ∗ Corresponding author. E-mail address: meguid@mie.utoronto.ca (S.A. Meguid). mainly focused on the simulation and fabrication of piezo-actuated diaphragms for use in micro fluid delivery systems. For example, Zhang and Wang [6] proposed a valveless piezoelectric-actuated micro fluid delivery system with a circular diaphragm for pumping fuel into a direct methanol fuel cell. Cui et al. [7] used numerical and analytical methods to characterize the static behavior of circu- lar piezoelectric-actuated diaphragms for micro-devices for drug delivery purposes. Kan et al. [8] fabricated a piezoelectric-actuated micropump with three serially connected chambers and showed that the use of more chambers leads to considerable enhancement of the overall performance of the proposed micro-device. Kang and Auner [9] analyzed the performance of a micro fluid delivery system employing a rectangular diaphragm by calculating its average static deflection using the commercial software ANSYS. In their work, they successfully verified their finite element results by comparing them with experimental data. Chandika et al. [10] proposed a sim- ple PZT-actuated micro fuel delivery system in a gasoline engine. They investigated the flowrate of the system using static and dynamic analyses and verified the obtained results experimentally. Zhang and Eitel [11] used a multi-layered package of conventional piezo-ceramics in the diaphragm of a piezoelectric-actuated micro- device. The experimental results obtained from their proposed planar design showed that the application of such multi-layered diaphragm significantly improves the overall performance of the https://doi.org/10.1016/j.sna.2019.111528 0924-4247/© 2019 Elsevier B.V. All rights reserved.