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When using groundwater as a primary energy source in combination with heat pumps, the groundwater is pumped from the groundwater zone, cooled in the heat exchanger of the heat pump, and then reinjected into the groundwater zone. The design of traditional groundwater heat pump plants is based on the use of a separate pumping and reinjection well. An alternative design is to use a single-well for both pumping and reinjection. However a minimum distance between well screens is required in order to prevent break-through, caused by short-circuiting of the cooled groundwater. The present paper describes a simplified mathematical model to be used to analyze steady-state operational temperature conditions for a single-well groundwater heat pump plant. The model is based on a finite element solution of the temperature distribution in the pumping and reinjection zones of the groundwater reservoir.

The current work investigates a method in 1D modeling of cooling systems including discretized cooling package with non-uniform boundary conditions. In a stacked cooling package the heat transfer through each heat exchanger depends on the mass flows and temperature fields. These are a result of complex three-dimensional phenomena, which take place in the under-hood and are highly non-uniform. A typical approach in 1D simulations is to assume these to be uniform, which reduces the authenticity of the simulation and calls for additional calibrations, normally done with input from test measurements. The presented work employs 3D CFD simulations of complete vehicle in STAR-CCM+ to perform a comprehensive study of mass-flow and thermal distribution over the inlet of the cooling package of a Volvo FM commercial vehicle in several steady-state operating points.

The rigid-ring tire model is a simplified tire model that describes a tire's behaviour under known conditions through various in-plane and out-of-plane parameters. The complex structure of the tire model is simplified into a spring-mass-damper system and can have its behaviour parameterized using principles of mechanical vibrations. By designing non-linear simulations of the tire model in specific situations, these parameters can be determined. They include, but are not limited to, the cornering stiffness, vertical damping constants, self-aligning torque stiffness and relaxation length. In addition, off-road parameters can be determined using similar methods to parameterize the tire model's behaviour in soft soils. By using Finite Element Analysis (FEA) modeling methods, validated soil models are introduced to the simulations to find additional soft soil parameters.