Performance analysis of an innovative kind of two-stage piston type expansion air engine

Qihui Yu,Xueqing Hao,Xin Tan

doi:10.1177/1687814018773860

Abstract

In small-scale compressed air energy storage system, expansion air engine is the key component. To improve the expansion air energy performance, an innovative kind of two-stage piston type expansion air engine is put forward. In this article, working principles of the new kind of expansion air engine are described. A mathematical model of the working processes is set up by analysis of the air engine. The characteristics of the expansion air engine are obtained by using the simulation technology. Results show that, first of all, with the same supply pressure, the efficiency of the new kind of expansion air engine is higher than that of the single stage expansion air engine by approximately 15%, which is about 1.31–1.56 times of that of the single stage air engine. Simultaneously, the output power of the new kind of air engine is higher than that of the single stage expansion air engine. Second, the efficiency and output power are mainly impacted by the closing angle of valve 1. Third, the bigger the cylind...

Highlights

Micro-energy network is one of the important developing trends of future energy system
The experimental results showed that the efficiency could be more than 25% by using air and the output power reaches 1.92 kW when the intake pressure is set at 2 MPa.[14,15]
This study aims to propose a method to enhance the efficiency of expansion air engines by constructing a new expansion air engine with two-stage expansion engine

Summary

Introduction

Micro-energy network is one of the important developing trends of future energy system. Many types of expansion air engines have attracted substantial attention,[3,4] which included turbomachinery engine,[5] screw engine,[6] scroll engine,[7,8] triangle rotor engine,[9] piston-type engine, and so on. Among these air engines, piston-type air engines have a good isentropic efficiency, a high output power and a long life.[10]

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Discussion

Conclusion