The Thermal Manikin testing system is designed and manufactured to evaluate the flame resistance and thermal resistance of firefighters' specialized clothing under direct flame exposure and heat flux.
During the project development, we had to address several challenges:
The testing system was required to incorporate 3 heat panels, each instantaneously consuming 80 kW. Consequently, for 3 panels, the total power demand was 240 kW. However, the substation generating electricity for the testing complex could only provide a capacity of 180 kW.
A pivotal criterion for the Thermal Manikin was its mobility. Nevertheless, the designated facility confronted spatial limitations (3×6×9 – in accordance with testing standards). Moreover, the direct exposure of the manikin to open flames and thermal flux introduced challenges to conventional solutions, such as employing a metallic cart or rail system.
During the design phase, a balance was required between the manikin’s mobility, mass, and construction cost. Achieving a 180-degree rotation and precise positioning demanded a drive with substantial mass, imposing constraints on vertical displacement drives and resulting in added complexities and increased cost of the testing system.
Our Role
Requirements analysis
Conceptual design
Engineering R&D
Mechanical and CAD design
Electronics design
Firmware (embedded software) development
FEA/FEM simulations
Thermal stress analysis
Prototype manufacturing & testing
Technical support
Technologies Used
For Enterprises
• R&D + design + manufacturing under ONE roof • Scale up and down your team • Intergrated hardware + software development • New technologies and research
In order to ensure that the power consumption of the standard panels did not exceed 180 kW, we conducted additional computer simulations. The calculations indicated that by modifying the structural design, it was possible to increase the efficiency of each panel.
The modification in the structural design involved the integration of reflectors, addressing two key issues: 1) Overheating of the thermal panel lamps due to scattered rays hitting adjacent bulbs; 2) A significant portion of thermal energy being directed non-perpendicularly to the emission plane and away from the thermal manikin.
After incorporating reflectors, the thermal panel exhibited the following characteristics: Efficiency (Coefficient of Performance) – 80% (a 30% increase); the distance from the panel at which a value of 40 kW/m2 was achieved – 15 cm. This solution resolved the energy consumption issue, as only 2 panels were now sufficient for testing the mannequin, instead of the initially required 3.
Implementing reflectors around the lamps of the thermal panels increased efficiency by 30%. Energy consumption was reduced by 1.5 times, as the enhanced efficiency of individual panels meant that only two units were required to achieve the necessary temperature for heating the space and manikin.
To implement the manikin’s movement mechanism, we needed to consider the room dimensions, the influence of high-temperature open flame, and ventilation ducts placement. We opted to develop a crane-beam system as existing solutions occupied significant space, impeding human passage and hindering the installation of room ventilation.
With a room height of 3 meters, the crane-beam was designed to allow unrestricted movement for an adult at full height.
However, the ventilation issue persisted, as our crane-beam design still couldn't accommodate the ventilation structure. Subsequently, we relocated the air ducts outside, while air intake was maintained inside the facility.
In addition to longitudinal movement, the manikin was to descend, ascend, and rotate 180° around its axis.
To achieve the required kinematics for the thermal manikin, we conducted calculations for moment of inertia and moment of friction. For rotation around its own axis, we employed a single-stage worm gear motor-reducer, chosen for its minimal inertial moment to avoid significant additional weight on the manikin. This approach was crucial to facilitate the selection of an actuator for vertical movement. The relatively low mass of the chosen rotation drive allowed us to use commercially available linear rod actuators with a piston speed of 10 mm per second.
Results and Benefits
EnCata developed the design of the testing system, manufactured it, and delivered it to the customer. The test trials yielded positive results. Currently, the Thermal Manikin testing system is in successful operation.