$\hbox{MnO}_{2}$ Nanowire Embedded Hydrogen Peroxide Monopropellant MEMS Thruster

Abstract

Feasibility of chemically synthesized MnO 2 nanowire catalyst embedded silicon microelectromechanical systems (MEMS) H 2 O 2 monopropellant microthruster has been demonstrated. Due to exothermic reaction process, sustenance of thrust generation does not require any heating of propellant thus minimizing electrical power requirement. The thruster device integrates inlet nozzle, microchannel, MnO 2 nanowire embedded reaction chamber, in-plane exit nozzle and a microheater in the silicon layer. Nozzle configuration and catalyst bed was designed using simple analytical equations to achieve complete decomposition of H 2 O 2 and maximum thrust force by controlling the propellant flow. Simulation of hydrogen peroxide decomposition process was carried out to evaluate the thermo-chemical characteristics. The MnO 2 nanowire has been obtained using a low-cost synthesis process and characterized using field emission scanning electron microscopy, Energy-dispersive X-ray spectroscopy, transmission electron microscopy, and X-ray diffraction studies. Thruster fabrication using micromachining process and its testing have been briefly described. The device is capable to produce 1 mN thrust and specific impulse of 180 s using 50 wt.% concentrated H 2 O 2 of flow rate 1.25 mg/s with total ignition energy of 44 J required for preheating the catalyst bed. Detailed thrust measurement was carried out with propellant mass flow rate for different throat area of exit nozzle, and the results were interpreted with theoretical model.[ 2012-0135]Index Terms-Microelectromechanical systems (MEMS), micropropulsion, microthruster, monopropellant, nanowire, thrust. include biomedical and inertial MEMS transducers, BioMEMS, and microfluidic biochips for clinical diagnostics, medical electronics, and very large scale integration unit processing. He played a key role in the development and growth of teaching and research activities in microelectronics technology, MEMS and biosensors, medical electronics, and thin film processing. He has been actively involved in setting up a state-ofthe-art advanced MEMS design and processing laboratory at IIT Kharagpur. He has authored more than 40 research papers in international journals and conference proceedings. He is the Principal Investigator of several research and consultancy projects in the area of MEMS and microsystems funded by various government and private agencies.

Study of the effects of preheated wall/plates in microthruster systems

“…Hence, the performance parameters of type 2 are higher than the two others. Kundu et al (2013) showed that there was a temperature gradient in a hydrogen proxide monopropellant microthruster at the chamber section. Therefore, in this Section, the effect of temperature gradient on the thruster performance is studied.…”

“…4 without heater plates, the wall temperature is 900 K). The increasing of the wall temperature can be performed by using hot wire coated walls (Kundu et al, 2013). For type 3, heater plates (with temperature 900 K) are inserted into the thruster (see Fig.…”

“…4 with heater plates). The overall geometry (but not the exact dimensions), the structure and idea of heating the fluid flow in type 3 is adapted from Kundu et al (2013), Hitt et al (2001) but not exactly with the same components. They fabricated and tested such a microthruster.…”

Recent Advances in MEMS-Based Microthrusters

“…The tested heating power of microthruster was up to 20 W and the inside temperature distribution was also measured by integrated RTDs, which showed a much better thermal performance. Kundu et al [69] presented a chemically synthesized MnO2 nanowire catalyst-embedded H2O2 monopropellant microthruster and the microheater realized by boron-diffused meanderline resistor was fabricated to preheat the reaction chamber. The structure design of the proposed microthruster with MnO2 nanowire embedded is shown in Figure 26.…”

A review of MEMS micropropulsion technologies for CubeSats and PocketQubes

“…Hydrogen peroxide is an interesting alternative since it does not need the level of precaution in handling it [71], [72]. One of its disadvantages is that organic materials are very likely to serve as a catalyst for its decomposition, therefore it might slowly decompose in the propellant tank due to minimum contact to undesired substances present in the storage.…”