Managing and estimating leaf transpiration for individual leaves is an essential part for understanding plant transpiration and plant-climate interactions. Leaves exchange water vapour and other gases through microscopic small openings, called stomata. Stomata are generally very small, in the order of 10 to 30 micrometres, and are distributed randomly over a leaf's surface. Stomatal coverage ratios also generally vary in between 0.1% to 2% for different plant species. Although their small size, they are able to efficiently transport water vapour to the air and take in CO₂ for photosynthesis from the outside. Computational Fluid Dynamics, CFD has proven to be a useful tool in the past to simulate air flows over leaves. In these studies, the effect of individual stomata is averaged out over the domain of the leaf by putting these leaves at a certain humidity, e.g. a fully wet leaf. In this study, a symmetric realistic leaf geometry with dimensions of 6cm by 2cm with individual stomatal sources is used to study individual leaf transpiration. Heat and mass transfer at the stomata of the leaf are simultaneously solved. Realistic leaf-air temperature differences are obtained. Different velocities and stomatal distributions are used in the study to see how this solution is different from a fully wet leaf. When radiation is included in the model, the stomata are at a higher temperature and therefore also a higher humidity, causing a larger water vapour gradient and a bigger transpiration rate. A one-dimensional model could be made in the future which is able to describe the humidity in function of the distance to the leading edge of the leaf. This model can then be implemented in future CFD-simulations, where a full plant geometry with individual leaves is solved.