The hottest simulation accelerates the supply of s

Thermal simulation accelerates the supply of smaller and quieter PCs to the market

Dr. Andy Manning, vice president of thermal engineering, flomerics, morborough, Massachusetts; The balanced technology expansion architecture (BTX) is a new PC motherboard architecture, which improves the cooling of key components and reduces the noise level and box size. From the perspective of heat, the system design based on the new motherboard architecture may have some challenges, because this new design has only two fans, rather than three to five

in order to help system builders, especially smaller manufacturers without a large number of engineers, a series of designs have been carried out to serve as the starting point for the mechanical design of different types of BTX systems. Using traditional construction and testing methods will cost a lot of time and high cost, because it needs to build and test a variety of prototypes. On the contrary, Intel uses Flotherm software of flomerics to evaluate a large number of potential designs from the perspective of heat and sound, and uses simulated diagnostic information to form optimized designs before the prototype production stage

btx heat improvement

btx heat improvement mainly comes from the use of straight air flow. The limited linear airflow layout allows a large number of motherboard components processors, chipsets, and graphics controllers to utilize the same primary fan airflow, thereby reducing the need for additional system fans while reducing the noise generated by the fan system. In some cases, it is also allowed to use fewer and cheaper heat sinks than the ATX scheme. Reducing air turbulence in a linear airflow system also improves system level sound effects. BTX layout supports better component layout of backplane i/o controller, which is important when the signal speed of external devices continues to rise. The size provided by BTX is smaller than the smallest size in the ATX motherboard architecture. The design uses the core components by increasing the number of system slots, so that the proportional damage resistance and shrinkage properties are quite important to increase to the tower size system. A key change in the BTX motherboard architecture is that the fan in the processor heat sink blows air through the processor from the side, rather than blowing air onto the processor. A key part of developing a new motherboard architecture is to prove that it can ideally reduce noise and box size while keeping all components in the box cool. Engineers conducted a large number of computer simulations in order to evaluate the performance of series designs according to the new standards and provide guidance to companies developing such designs

Entertainment PC

BTX Entertainment PC is designed to install a large number of other audio-visual devices and optimize them to meet strict sound goals. Compared with a typical personal computer, its industrial design is more similar to consumer electronics. This reference design is particularly interesting because the traditional ATX design has never been able to meet the application requirements in this regard. The biggest challenge facing the design is to meet the strict sound requirements of this application

btx system structure is very suitable for fan deceleration, which can reduce the fan speed by greatly reducing the temperature and airflow impedance. However, the entertainment reference design must have a suitable front baffle, and the front baffle is not affected by the vents. The basic principle used in this design is to set the side, bottom and top panel vents near the inlet of the thermal module to minimize the inlet impedance, otherwise the fan speed of the thermal module must be increased. Engineers also set higher power components at the main air flow generated by the thermal module

safe temperature

of course, when engineers developed this preliminary conceptual design, they were not sure whether this design scheme could maintain the temperature of components at a safe level. They have no time or resources to produce a large number of prototypes, which are necessary to verify the conceptual design by trial and error. However, they do have FL result judgment: other's thermal simulation software. They developed a preliminary mechanical layout, modeled the design in Flotherm software, and observed the results. The temperature graph shows the hot spots in the dual in-line memory module (DIMM) through the chassis. On the other hand, the air velocity and direction profile show that the hard disk drive restricts the air flow from the rear of the box

engineers used thermal simulation capabilities to quickly determine the impact of design changes. They added a vent to the memory to reduce the inlet impedance of the area, and evaluated its different geometric patterns and vents with openings of 20% to 80% from the perspective of heat and sound. They estimate the acoustic signature map through manual calculation, so as to evaluate the sound effect. Using this method, they can reduce the thermal impedance and eventually cool the DIMM

most BTX reference designs set the power supply on the left side of the box, but this is not a requirement for the motherboard architecture. Engineers believe that setting it on the right side can achieve better airflow effect. They made changes and observed the results and found that their intuition was correct. However, here, when the thermal module fan is idling, the noise generated by the system is 3.6 bels (BA) sound power

the thermal simulation experiment evaluates the design under various fan speeds, starting from 1800 rpm and reducing the speed until the components begin to overheat. In this case, to avoid rusting, the fan speed is reduced to 650 rpm, so that the sound target can be achieved. Although the initial running speed of the fan was not 650 rpm, the engineers made suggestions to the manufacturers and persuaded them to change the control system so that the fan could run at this speed

the resulting reference design - and other reference designs developed are used by the system builder to reduce the time required for BTX system design. System builders almost never copied the reference design, but the proven design with known thermal and sound characteristics from the beginning helped them a lot. In order to further simplify the design process for customers, a series of thermal simulation templates for BTX design have been developed. Users of Flotherm software can select these reference designs from the document library and make changes according to their own wishes, so as to provide added value to their customers. Flotherm currently includes four BTX designs, micro towers, pocket towers, desktops with one or two thermal modules, and nine ATX reference designs. Additional reference designs will be added in the near future. (end)