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Jet pumps are a viable option of pumping fluid if a pressurized flow stream is available as an energy source. For a Ford engine cooling circuit an effort was undertaken to improve an existing (conventional) jet pump design which could not meet the more demanding pumped flow requirements. Various virtual jet pump designs were analyzed using 3D CFD where the pumped flowrate was used to evaluate the effectiveness of the design. It was found that the existing design could not be modified to provide the needed pumped flow rate. It was decided to forgo the current design and develop a completely new configuration. This effort produced many design variances which were evaluated and resulted in a final design that closely achieved the pumped flow rate requirements. As new designs were evaluated through the process, particular geometrical aspects were observed to induce flow characteristics which improved the pumped flow performance.

A jet pump (also known as ejector) uses momentum of a high velocity jet (primary flow) as a driving mechanism. The jet is created by a nozzle that converts the pressure head of the primary flow to velocity head. The high velocity primary flow exiting the nozzle creates low pressure zone that entrains fluid from a secondary inlet and transfers the total flow to desired location. For a given pressure of primary inlet flow, it is desired to entrain maximum flow from secondary inlet. Jet pumps have been used in automobiles for a variety of applications such as: filling the Fuel Delivery Module (FDM) with liquid fuel from the fuel tank, transferring liquid fuel between two halves of the saddle type fuel tank and entraining fresh coolant in the cooling circuit. Recently, jet pumps have been introduced in evaporative emission control system for turbocharged engines to remove gaseous hydrocarbons stored in carbon canister and supply it to engine intake manifold (canister purging).

Fuel level sensors are used to indicate the amount of fuel in the tank of an automobile. The most common type of fuel level sensor is the float-arm sensor in which a float is connected to a resistance band via an arm. The fuel volume inside the tank sets the height of the float which in turn is converted to a resistance value. This resistance value is converted into gauge reading that is displayed on the dashboard. Whereas this method is widely popular due to its low cost and durability, fuel slosh phenomenon imposes a major challenge. The fuel slosh waves under numerous driving maneuvers impose dynamic drag/lift forces on the float which result into fluctuations in its position (i.e. float height). Under severe acceleration or braking maneuvers, the float can actually submerge inside the liquid and fail to predict location of the free surface. These fluctuations can cause erroneous fuel indication.

Several emission performance tests like Butane Working Capacity (BWC), Cycle Life, and ORVR load tests are required for the certification of a vehicle; these tests are both expensive and time consuming. This paper presents a test process based upon analytical simulation of BWC of an automotive carbon canister in order to greatly reduce the cost incurred in physical tests. The computational model for the fixed-bed system of a carbon canister is based upon non-equilibrium, non-Isothermal, and non-adiabatic algorithm to simulate the real life loading/purging of hydrocarbon vapors from this device.