Climate sensors in trucks. Master thesis at Volvo Group.

Abstract

Good air quality and temperature is not only pleasant but also a health issue and since the cabin of a truck is a work environment, the same demands as in other working spaces should be met. Volvo Group is a company which has the will of continuously improving their technology and has a strong safety culture, therefore the climate in the cabin is hence considered an important issue. There are four truck brands within the Volvo Group: Volvo Trucks, Mack Trucks, Renault Trucks and UD Trucks. The intention is that this thesis can contribute with knowledge to all the truck brands within the Volvo Group. To control the climate inside the cabin of a truck several sensors can be used. This master thesis aims at increasing the knowledge, mainly concerning a possible future solar sensor. A solar sensor in combination with a Climate Control Unit (CCU) can be used to forecast an increase in temperature in the cabin and to compensate for the thermal discomfort felt by a person situated in sunlight. The thesis started with a simulation of the heat balance of the truck in order to find the required accuracy and time constant of the solar sensor. Tests were performed to evaluate how a solar sensor would be affected by the windshield and finally a benchmark of the solar sensor was performed. The simulations show that the time constant of a solar sensor should be shorter than two seconds and that the accuracy should be within ± 6 W. There are several manufacturers of solar sensors with shorter time constants than required, however the accuracy of solar sensors is difficult compare between the manufacturers. The design of the sensors and their casing has a great impact on the performance of the sensor, as well as the placement of the sensor and the materials in the near surrounding. It is difficult to predict exactly how a specific sensor will perform in a particular application, hence physical tests will be needed to get exact results.