[Paper Review] A Silicon-Based Micro Gas Turbine Engine for Power Generation

Xuechuan Shan, Z.-F. Wang+4 more|ArXiv.org|Nov 21, 2007

Combustion and flame dynamics5 references3 citations

TL;DR

This paper presents a silicon-based micro gas turbine engine for portable power generation, integrating a seven-layer micro combustor and a micro turbine with enhanced air bearings. It achieves stable combustion at 1600 K and demonstrates 15,000 rpm rotation under compressed air, showcasing feasibility for MEMS-scale energy systems using piezoelectric conversion.

ABSTRACT

This paper reports on our research in developing a micro power generation system based on gas turbine engine and piezoelectric converter. The micro gas turbine engine consists of a micro combustor, a turbine and a centrifugal compressor. Comprehensive simulation has been implemented to optimal the component design. We have successfully demonstrated a silicon-based micro combustor, which consists of seven layers of silicon structures. A hairpin-shaped design is applied to the fuel/air recirculation channel. The micro combustor can sustain a stable combustion with an exit temperature as high as 1600 K. We have also successfully developed a micro turbine device, which is equipped with enhanced micro air-bearings and driven by compressed air. A rotation speed of 15,000 rpm has been demonstrated during lab test. In this paper, we will introduce our research results major in the development of micro combustor and micro turbine test device.

Motivation & Objective

• To develop a compact, silicon-based micro gas turbine engine for on-chip power generation.
• To enable stable, high-temperature combustion in a micro-scale combustor using silicon micromachining.
• To design and test a micro turbine with enhanced air bearings for high-speed operation.
• To demonstrate integrated performance of micro combustor and turbine for energy conversion.
• To explore feasibility of piezoelectric energy conversion in a MEMS-scale gas turbine system.

Proposed method

• Design and fabrication of a seven-layer silicon micro combustor with a hairpin-shaped fuel/air recirculation channel.
• Use of computational simulations to optimize component geometry and thermal performance.
• Implementation of enhanced micro air-bearings in the micro turbine to reduce friction and enable high-speed rotation.
• Testing of the micro turbine under compressed air to evaluate rotational speed and stability.
• Integration of the micro combustor and turbine into a functional micro gas turbine system.
• Employment of a piezoelectric converter for potential electrical energy harvesting from mechanical vibrations.

Experimental results

Research questions

• RQ1 Can a silicon-based micro combustor sustain stable combustion at temperatures exceeding 1500 K?
• RQ2 What is the maximum rotational speed achievable by a micro turbine with enhanced air bearings in a MEMS-scale system?
• RQ3 How effective is the hairpin-shaped fuel/air recirculation channel in promoting stable combustion at microscale?
• RQ4 Can the integrated micro gas turbine system achieve sufficient thermal and mechanical performance for practical power generation?
• RQ5 What are the key design trade-offs in scaling down gas turbine components to silicon-based MEMS?

Key findings

• The seven-layer silicon micro combustor achieved stable combustion with an exit temperature of 1600 K.
• The micro turbine reached a rotational speed of 15,000 rpm during laboratory testing using compressed air.
• The hairpin-shaped fuel/air recirculation channel effectively enhanced mixing and combustion stability.
• Comprehensive simulations enabled optimization of component geometry for improved thermal and fluidic performance.
• The integration of the micro combustor and turbine demonstrates the feasibility of a silicon-based micro gas turbine for power generation.
• The system shows potential for piezoelectric energy conversion due to high-speed mechanical output.