Executive Summary : | Hybrid rockets are combination of solid and liquid rockets which typically use solid fuel and liquid/gaseous oxidizer. The hybrid rockets have high density specific impulse and are controllable along with stop and restart capability. Further, the design of hybrid rockets is simple compared to liquid rockets as only one liquid/gas is to be handled and the use of carcinogenic liquids can also be avoided. These features makes hybrid rockets suitable candidate for the launch vehicle and human space flight. Despite of various advantages, hybrid rockets suffer from one disadvantage which is low regression rate of solid fuel. In order to utilize the various advantages of hybrid rocket, it is imperative to devise methods to improve the regression rate of fuel. The addition of foreign materials such as catalysts, aluminum and ammonium perchlorate in the fuel is the most common method to improve the regression rate. Various researchers have carried out study in this direction, however, the improvement in specific impulse was overcome by requirement of higher oxidizer to fuel (O/F) ratio, which results in larger size of the system as more oxidizer needs to be carried. The use of high energy density material (HEDM) is another attractive method to improve the performance by improving the energetic of the solid fuel. HEDM are strained hydrocarbons with C-C bond angle less than 109.5. Due to higher strain energy, the heat of combustion of these hydrocarbons is more compared to regular hydrocarbons. Recently, researchers have synthesized strained hydrocarbons referred as ivyanes based on cyclopropyl rings. The theoretical calculation shows that the use of ivyanes improve the specific impulse and the peak specific impulse can be obtained at much lower O/F, thereby, reducing the size of the system. Since, the heat of combustion of ivayanes is high, the addition of ivayanes in the solid fuel could improve the regression rate. Therefore, an experimental study is proposed to determine the performance of solid fuel mainly paraffin wax with the addition of ivyanes. |