Numerical simulation of positioning error caused by air-flow-induced vibration of head gimbals assembly in hard disk drive

Shimizu, Hirofumi; Shimizu, Toshimi; Tokuyama, M.; Masuda, Hiromitsu; Nakamura, Shuichi

doi:10.1109/tmag.2003.808928

Cited by 50 publications

(16 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The rapid airflow in the interior of a HDD is highly unsteady with partly laminar and partly turbulent regions, and consists of three regions: 'a solid body inner region near the hub, an outer region dominated by counter rotating vortices and a boundary layer region near the shroud' [6,7]. The turbulent airflow generates unsteady pressure fluctuations or aerodynamic force known as 'windage', causing structural vibration of the HDD components [8].…”

Section: Past Work On Hdd's a Flow-induced Vibration (Fiv)mentioning

confidence: 99%

See 1 more Smart Citation

Structure Optimization Study of Hard Disk Drives to Reduce Flow- Induced Vibration

Ng¹

2011

TONUMJ

View full text Add to dashboard Cite

Abstract:In this paper, the effects of two flow-induced vibration (FIV) mitigation components on hard disk drive (HDD) airflow, vortex splitters and flow diverters, were verified. The edges of the components were also modified by filleting and the resulting effect on airflow determined. A perspective review on HDDs and their operation, and the mechanism and mitigation of FIV was discussed. Three suitable turbulent models from the commercial fluid flow solver FLUENT were briefly compared. A preliminary study was then carried out on a simplified HDD model to determine the mesh fineness required in HDD turbulent flow simulation in order to obtain accurate results. Another study was done to compare between the RNG k-and LES turbulent models in FLUENT. A full 3.5 inch commercial HDD model was used and results indicated that the LES model was suitable for turbulent flow modelling of a HDD. Lastly, flow simulation of three HDD models with different FIV mitigating features was carried out. Results showed that flow diverters are effective in reducing airflow turbulence in HDD for Re of 12.5x10 4 . The modification and filleting of component edges to make them more aerodynamic streamlining was shown to be less effective but further studies should be done to conclude on the effectiveness of filleting. An optimized HDD structure which includes both vortex splitters and flow diverters, with the filleting of component edges recommended but not mandatory was proposed.

show abstract

Section: Past Work On Hdd's a Flow-induced Vibration (Fiv)mentioning

confidence: 99%

“…Shimizu et al [8] revealed that pressure fluctuations were generated by vortex shedding from the suspensions and the E-block (HDD arm). Another study also showed that airflow directed towards the outer circumference of the disks collides with the arm, creating a wake region.…”

Section: Past Work On Hdd's a Flow-induced Vibration (Fiv)mentioning

confidence: 99%

Structure Optimization Study of Hard Disk Drives to Reduce Flow- Induced Vibration

Ng¹

2011

TONUMJ

View full text Add to dashboard Cite

show abstract

“…Many researchers have investigated airflow and flow induced disk flutter and head gimbal assembly vibration by numerical simulation or experimental measurement as reported by Humphrey et al (2002), Shimizu et al (2003), Tsuda et al (2003), Nakamura et al (2005), Aruga et al (2007), and Zhang et al (2008).…”

Section: Introductionmentioning

confidence: 99%

Mitigation of flow induced vibration of head gimbal assembly

et al. 2009

View full text Add to dashboard Cite

The airflow of a 10,000 rpm hard disk drive is simulated using the LES turbulent model. The critical parameters for using LES model to get the correct/reliable result are discussed. The flow induced vibration of the head gimbal assembly is calculated with the obtained fluid force acting on the head gimbal assembly (HGA) and compared with measured results. Good agreement is observed between the measured and simulated results. The optimization of the airflow is further carried out to reduce the flow induced vibration of the HGA. It is found that almost 50% reduction of flow induced vibration of the HGA can be achieved with the proposed modifications for airflow optimization.

show abstract

“…Extensive effort has been made in the past decades in modeling and simulation (M&S) of HDDs for dynamics and vibration analysis of various disk-spindle systems and voice coil motor (VCM)-actuator assemblies, fluid dynamics analysis of disk flutter, and aerodynamic vibration analysis of arm/suspensions (Shen et al 2004;Gao et al 2005a;Tatewaki et al 2001;Shimizu et al 2003). These M&S studies, however, have been carried out from the perspective of enhancing the data read/write precision.…”

Section: Introductionmentioning

confidence: 99%

A study of acoustic noise generating mechanisms of small form factor HDDs

et al. 2009

View full text Add to dashboard Cite

A combined experimental and numerical study of the acoustic noise from a small form factor hard disk drive (HDD) is made to investigate the relative contribution of structure-borne idle noise to the total generated noise. Initially, the idle noise of a 1.8 00 HDD was measured in an anechoic chamber, and a clear high-frequency peak is found in its total idle noise frequency spectrum. Then the modeling and simulation (M&S) of the top cover vibration and the associated sound radiation are performed to identify the dominant source and transmission path causing this noise peak. The M&S process consists of a 3D structural finite element (FE) modeling of the HDD to calculate the frequency-domain vibration response of the top cover, and a boundary element (BE) modeling of the HDD for calculating the radiated sound pressure. The loading specified in the FE model is motor torque ripple: the dominant electromagnetic excitation of fluid dynamic bearing spindle motor for HDDs. Finally, the obtained acoustic BE results of the sound pressure levels at a selected field point are compared to those measured physically in the chamber. It is shown that for the HDD considered, the coincidence of a high-frequency resonant mode with the fifth harmonic frequency of motor torque ripple is responsible for the high-frequency peak noise in the idle noise spectrum.

show abstract

Numerical simulation of positioning error caused by air-flow-induced vibration of head gimbals assembly in hard disk drive

Cited by 50 publications

References 7 publications

Structure Optimization Study of Hard Disk Drives to Reduce Flow- Induced Vibration

Structure Optimization Study of Hard Disk Drives to Reduce Flow- Induced Vibration

Mitigation of flow induced vibration of head gimbal assembly

A study of acoustic noise generating mechanisms of small form factor HDDs

Contact Info

Product

Resources

About