Flame Temperature Measurement In Secondary Combustion Chamber Based On Image Processing

It is a key technique to enhance the combustion efficiency in the secondary chamber to increase the solid rocket ramjet capabilities.Temperature in the secondary chamber reflects the level of combustion efficiency,so it is very important to investigate the combustion in the secondary chamber.The temperature field can be used to foster an in-depth understanding about the combustion process and the mechanism of combustion.It can also be used to provide direction for thermal protection.So advanced and effective temperature-measurement method is of great worth for the development of solid rocket ramjet.The working characteristic of color CCD is investigated.Based on law of radiation and theory of color CCD,colorimetric temperature-measurement method is proposed.The error of temperature-measurement method is analyzed.Improved colorimetric temperature-measurement method and three-color temperature-measurement are presented.A test was conducted on a direct-connect test bed for ducted rocket motor which consisted of a secondary combustion chamber with a window.A high-speed photography was used to collect the image data of the flame. Image Processing technique is adopted to take out the flame and abate the noise,the temperature field of the secondary combustion chamber is calculated.The BP neural network is used as a new temperature-measurement method,which shows its great superiority for its convenience and low cost.The BP neural network can be used as a real time temperature-measurenment method for the secondary combustion chamber.Based on flame radiative transfer equation,the cross-section temperature field solving model is established.According to the model,the cross-section temperature field of secondary combustion chamber is calculated by algebraic reconstruction techniques.