Spectroscopic Measurement Of Gas Temperature In Small Internal Combustion Engines

Download or read book Spectroscopic Measurement of Gas Temperature in Small Internal Combustion Engines written by Matthew J. Deutsch and published by . This book was released on 2016 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internal Combustion Engines (ICE) revolutionized transportation at the dawn of the 20th century. Continuous refinement of the theory and design of ICE has allowed them to become so well optimized to the task of human transport that they are often taken for granted, only thought of on the rare occasion when they fail to work properly. Nobody speaks about the challenge of designing an ICE that is acceptable for the task of moving people from one place to another. Today, in the age of the remotely piloted aircraft (RPA), another opportunity arises to instigate the continuous refinement of the ICE to a novel task. Small ICE have been used to propel small model aircraft for decades, but the recent exponential growth in demand for RP A in military applications has given rise to an expectation from small ICE which far surpasses current capabilities: RPA require the ability to operate at higher altitudes, in more extreme environmental conditions, and with greater fuel efficiency than is currently possible. Small internal combustion engines, particularly those ranging in power from 1 kW to 15 kW, propel many Group 1 and Group 2 remotely piloted aircraft (RPA) platforms that play an increasingly significant role in the Department of Defense. Most engines used for defense applications are commercial off-the-shelf products, designed for hand tools and hobby aircraft. Efficiency of these engines is low and thermal loss is a significant contributor to the energy loss. Existing thermal energy loss models are based on data from much larger engines. Whether these loss models scale to the engine size class of interest, however, has not yet been established. The Small Engine Research Bench (SERB) was used previously to measure spatially and temporally averaged heat flux, as well as local, instantaneous heat flux at several external locations, for a series of small engines. This investigation will obtain time averaged crank-angle-resolved measurements of the in-cylinder gas temperature using Fourier transform infrared (FTIR) absorption thermometry. The results, coupled with heat flux measurements, will enable the validation or refinement of existing thermal energy loss models.- author's summary