A medical ventilator has to function under all circumstances in ambulances and in the field. This is not only important in drought and warm conditions but also during heavy rain or frost. For the development of a compact airtight respirator the internal heat had to be simulated. Under the requirement that the air not be supplied above 40 °C at the patient, under all circumstances. Because the electronic case is airtight, most of the produced heat can only be dissipated by convection to the environment.
CFD and heat simulation of ventilator
Many ideas already existed for the compact portable respiratory system at Dräger. The identification of the total energy management was important. This included small fans, internal heat production of several electronic component, the air pump and the transfer of heat to the surroundings. Particular stress was placed on the non-isothermal calculation, for which air flow in the device and heat transfer to the environment are taken into account. The dimensions of the portable device were pre-specified, and within these measurements the design had to function optimally. During the FEM (Finite Element Method) simulation some common cooling fins and cooling systems were tested, to get an insight into the total efficiency of the heat transfer.
Cooling medical ventilator
The FEM simulation revealed that the medical ventilator met the needs, after several adjustments were done in the area of heat transfer by using convection to the surrounding air. Even under extreme weather conditions as were listed by Dräger, its proper functioning was proved by FEM. Because the FEM analyses provided several potential designs, a choice could be made for an optimal design and conduct field tests. An important phase, if it concerns emergency settings.