Effect of internal leakage on torque converter characteristics

Abstract

To understand the effect of internal leakage on the torque field and characteristics of a torque converter (TC), a transient analysis was performed on the internal flow of a TC and the pressure pulsation characteristics of monitoring points in the convection channel. It was found that dividing the leakage area of the TC into a separate watershed improved simulation accuracy by 4%. When there was a leakage area, there were distinct collision, mixing, and assimilation stages between the leakage flow and the main flow. These phenomena caused energy loss that was highest at low speed ratios. However, the leakage flow always accounted for 12% of the main flow regardless of the speed ratio. At the same time, the leakage flow had a larger influence on pressure pulsation inside the TC and especially the low frequency band was more substantial. This shows that the leakage area has a large influence on the TC performance, energy loss, and flow state. Analysis of the leakage area showed that reducing the leakage area helps to improve powertrain performance and fuel economy.

Research on aerodynamic characteristics of two-stage axial micro air turbine spindle for small parts machining

“…The validity of the simulation model was verified when the inlet pressure was 300kPa and the rotation speed was 100,000, as shown in Figure 4(b). 3 When the number of grids is more than 4 million, the total output torque is within the allowable error range. Considering the efficiency and economy of simulation, the total number of grids is 3,997,545 and the total number of nodes is 709,923.…”

“…With the extensive demand for miniaturization and intelligentization of products in the fields of robotics, new power devices, modern medicine, and biological engineering, the processing of precision parts with characteristic sizes from microns to millimeters has attracted extensive attention. 1–3 As a key component in micro-cutting technology, a micro-spindle should not only ensure a high rotation speed and high turning accuracy but also have a compact structure, compact size, and convenient installation. 4–6 Because of their advantages such as easy to realize high speed, no heating during operation, compact structure, and high power density and durability, air turbines have been widely used in micro-spindles, and researchers have carried out a number of relevant studies.…”