The Development And Application Of A New Smoke Machine

In China, forest pest and diseases outbreak widely and seriously in the resent years. The technology of drug loaded smoke is an important approach to control them. Pulsed smoke machine is a kind of plant protection machinery which is efficient and low cost in controlling forest pest and diseases. Combustion chamber-nozzle structure and carburetor are the key components of the pulsed smoke machine. Its mechanical structure, parameter, fluid morphology of combustion products and correlative thermal performance, all of them would make an directly impact on operational stability and fumation of the pulsed smoke machine, further affecting on controlling pests and diseases. Therefore, intensive study on the parts of combustion chamber and reducing its weigth will be of very great significance.This study discusses the working mechanism of existing pulsed smoke machine, expounds some important fluid parameters of pulsed smoke machine by establishing combustion chamber-nozzle structure mathematical model, such as the unary steady flow characteristics of fluid in combustion chamber-nozzle and fluid parameters of variable cross sections of entropy flow characteristics. Meanwhile this dissertation confirms the external configuration of combustion chamber-nozzle structure and select a correct shape of the nozzle (tapered nozzle), in order to design a new type of spiral U-tube structure and provide a vital technical support for pulsed smoke machine to achieve portability. On this foundation, the author analysises the pulse combustion process which has a kind of high temperature, high-speed and high pressure airflow in the combustion chamber-nozzle structure and the carburetor, researches the inherent frequency of oscillatory system formed in pulsed smoke machine internally, and designs a new pressurized balanced carburetor. In addition, this design using the LsbVIEW as a virtual design platform in order to acquire and measure the outlet temperature signal of the combustion chamber-nozzle structure with modular design and graphical programming method. Accroding the important pulsed smoke machine operating parameters based on Lab VIEW, the author collects and measures a few of informations such as the instantaneous engine fuel consumption and the amount of instantaneous spraying used smoke machine, and designs the relevant interactive interface programs.The primary results of the dissertation are summarized as follows:1. A new spiral U-tube structure is designed, which can improve the efficiency of pulsed smoke machine obviously, meanwhile its size and weight are both reduced compared with traditional pulse smoke machine.2. A new pressurized balanced carburetor is designed, which can improve the stability and start-up performance of the pulsed smoke machine effectively. 3.Two key components, combustion chamber-nozzle structureand and carburetor of pulsed smoke machine, have been redesigned renewedly.It means that a new pulsed smoke machine has been assembled and it also obtaines the patent awarded by State Intellectual Property Office of the People's Republic of China.(Patent No.:201120282931.7)4. The outlet temperature of combustion chamber-nozzle structure, nozzle transient temperature curve, engine instantaneous fuel consumption, the amount of instantaneous spraying of smoke machine and other relevant important datas are all acquired by analyzing important parameters of the design of new pulse smoke machine used the LsbVIEW virtual platform. And the relevant interactive interface programs are also designed.5. Using the new pulsed smoke machine with the laboratory-made15%buprofezin-cypermethrin hot fogging concentrate to control Parasaissetia nigra Nietner, the effect on imago and nymph are88.96%and90.99%respectively that can meet the design requirements. Its control effect is equal to the traditional TS-35pulse smoke machine.But the new pulsed smoke machine is lighter, more convenient to carry, lower labor intensity and more suitable in the hillside operations compared with traditional pulse smoke machine.