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To reduce the amount of carbon dioxide released from transportation the EU has implemented legislation to mandate the renewable content of petrol and diesel fuels. However, due to the complexity of the combustion process the addition of renewable content, such as biodiesel and ethanol, can have a detrimental effect on other engine emissions. In particular the engine load can have a significant impact on the emissions. Most research that have studied this issue are based on steady state tests that are unrealistic of real world driving and will not capture the difference between full and part loads. This study aims to address this by investigating the effect of renewable fuel blends of diesel, biodiesel and ethanol on the emissions of a compression ignition engine tested over the World Harmonised Light Vehicle Test Procedure (WLTP). Diesel, biodiesel and ethanol were blended to form binary and ternary blends, the ratios were determined by Design of Experiments (DoE). The total amount of emissions for CO, CO 2 and NO x as well as the fuel consumption, were measured from a 2.4 L compression ignition (CI) engine running over the WLTP drive cycle. The results depicted that percentages smaller than 10 % of ethanol in the fuel blend can reduce CO emissions, CO 2 emissions as well as NO x emissions, but increases fuel consumption with increasing percentage of ethanol in the fuel blend. Blends with biodiesel resulted in minor increases in CO emissions due to the engine being operated in the low and medium load regions over the WLTP. CO 2 emissions as well as NO x emissions increased as a result of the high oxygen content in biodiesel which promoted better combustion. Fuel consumption increased for blends with biodiesel as a result from biodiesel's lower heating value. All the statistical models describing the engine responses were significant and this demonstrated that a mixture DoE is suitable to quantify the effect of fuel blends on an engine's emissions response. An optimised ternary blend of B2E9 was found to be suitable as a 'drop in' fuel that will reduce harmful emissions of CO emissions by approximately 34 %, NO x emissions by 10 % and CO 2 emissions by 21 % for transient engine operating scenarios such as the WLTP drive cycle.

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A temperature controller has been developed using a platinum resistance thermometer in a bridge with inductively-coupled ratio arms. It is capable of maintaining water bath temperatures constant to within ±25 microdegrees Celsius for 24 h in an environment varying as much as ±1.5°C at any temperature from 18 to 28°C. The sensitivity of the controller approaches the theoretical limitation imposed by Johnson noise. The design makes possible control dials which are direct reading in °C.