I have some workload which needs to be run a few times per week. It requires some heavy computational work and runs about one hour (with 16 cores and 32gb memory). It is possible to run it in a container.
Azure offers many different possibilities to run containers. (I have no knowledge of most of the Azure services, so my conclusions might be wrong.) Firstly, I thought Azure Container Instances is perfect for this scenario, but it only offers containers with up to 4 vCPU and 16gb memory. There is no need for orchestration with a single container, so Azure Kubernetes Service and Azure Service Fabric come with too much overhead. Similarly, Azure Batch also offers computational clusters which are not needed for a single workload.
Which Azure service is the best fit for this use case?
While a "best fit" question is likely to be closed. Anyways, here's a suggestion.
Don't dismiss AKS. You can easily create a 1 node cluster using a VM that fits your required configuration. Using the standard SLA, you don't pay for the master node and you can stop your cluster after each run and stop being charged. No need to bother about orchestration, see this as a VM that has everything to run your container that you'll use like an ACI.