Undamped Critical Speed Map

Undamped critical speed analysis is very useful to understand the critical speed and mode shape characteristics briefly. Based on undamped critical speed map, the amplification factor as well as rotor behavior can be predicted.

Lateral Vibration Analysis

INERTANCE has performed the lateral vibration analysis (rotor dynamics analysis) with necessary design tools for turbo-machinery that includes centrifugal and axial compressors, centrifugal pumps, steam & gas turbines, motors, and gear applications. The rotor components including blades, impellers, etc have been modeled based on manufactured drawings, which can generate a mass-elastic lateral model of rotor assembly.

INERTANCE has a capability to perform below kinds of rotor dynamics analysis.

• Lateral vibration analysis
• Rotor dynamics analysis
• Damped eigenvalue (Critical speed) analysis
• Undamped critical speed map
• Train lateral vibration analysis
• Mode shape
• Campbell diagram analysis
• Bearing stiffness and damping coefficients
• Separation margins as per API requirements
• Forced response analysis (Unbalance response analysis)
• Bearing clearance assessment
• Stability analysis
• Log decrement
• Oil whirl and whip against rotor instabilities
• Transient analysis
• Forward and backward mode
• As per API 610, 611, 612, 617, 672, 684, etc. (Any other API Standard)

In addition, the linearized coefficients are calculated for various bearing types with application of any seal type step by step. INERTANCE can provide various kinds of rotor dynamics analysis as requested in API standards as below.

Field Balancing

In case the turbo-machinery has the vibration issue caused by unbalance, INERTANCE can perform the field balancing. In addition to that, INERTANCE has applied single and dual plane method, and also verified the balancing technic without phase measurement. 

INERTANCE has a capability to perform below kinds of Field balancing work.

• Field balancing for rotating equipment
• Conditional monitoring for rotating equipment
• Root cause analysis (RCA) for vibration trouble
• Single plane balancing
• Dual plane balancing
• Single plane balancing without phase
• Dual plane balancing without phase
• Pump, Compressor, Coupling, Turbine, etc
• Residual unbalance check
• Trim balancing
• Application for trial weight, rotor sensitivity
  

Noise Survey

INERTANCE has a capability to perform the noise survey with valid measurements at any necessary locations. Ambient noise survey will be used as back ground data for noise contour map, and the noise verification survey will be performed after finalizing the noise allocation study.

Noise survey include below kinds of activities.

• Ambient Noise Survey
• Noise Verification Survey
• Octave band Sound Level Meter
• A-Weight, dB(A)
• Noise Research
• Sound Recording and Reproduction
• Environmental Noise Measurement
• Plant Noise Measurement
• Indoor Noise Measurement

Noise survey has been performed with below purposes.

– To measure the noise generated by outside noise source

– To perform the survey at plant boundary limits

– To check the work area noise in plant facilities

– To measure the environmental noise by road traffic and rail road

– Noise survey around residential area

Noise Barrier

The location and height of noise barrier has to be carefully designed according to relation of source and receiver to provide the high efficiency for noise reduction. The materials of barrier have been selected based on their insertion loss as well as environment and customer’s requests.

Acoustic Insulation

Acoustic insulation has to be applied on surface of pipes, valves, pumps and compressors, etc. in order to reduce of the transmitted noise. These kinds of noise sources are caused from long pipe radiating the noise, and their thickness and material density have to be carefully designed with various experiences.

Acoustic Louver

Silencer and acoustic louver shall be applied to reduce noise level in all opening area. However, it is sometimes limited to apply the silencer due to its large volume space with accessibility to equipment. In this case, the application of acoustic louver should be considered with optimized sizing.

Silencer

Silencers have been applied to reduce the room background noise transmitted via duct system from air handling units, and to provide the effective ventilation as parts of acoustic enclosure together. The section areas of splitters have to be designed carefully in order to minimize the pressure drop of fluid, and it should be noted that the high velocity inside of silencer has possibility to generate self-exciting noise.

Enclosure

Acoustic enclosures have been designed to reduce the transmitted noise to sensitive receivers, and they have to be considered with combination of isolation, absorption, damping as well as ventilation. The thickness of acoustic transmitted panels has to be constructed with the dominant frequency of noise source, which should be installed to minimize any noise leakage. Large noise enclosure shall be sometimes designed in such way so that the operating and maintenance activities can be conducted.

Noise Control Design

INERTANCE can design the powerful & compact noise control devices, which have been applied to various noise sources to keep the relevant noise limits.

INERTANCE has a capability to perform below kinds of noise control design.

• Noise barrier
• Sound Attenuator
• Silencer
• Stack Noise Control
• HVAC Duct Noise Control
• Sound Baffles
• Acoustic Louver
• Noise Control & Mitigation
• Room Criteria Assessment
• Acoustic Insulation
• Sound Absorption
• Noise propagation
• Material Transmission Loss
• Frequency Spectrum Phenomenon
• Ear Protection

Many kinds of noise reduction facilities have been designed and installed as follows;

Sound Coverage Study

The arrangement of loudspeakers is the important to share the central notification in plant work area, specially in such emergencies like fire, toxic fluid leakage, etc. INERTANCE can provide the sound coverage study to predict the sound pressure level helping to design the clear alarm tones and message.

Indoor Noise

There are many kinds of spaces in building with own uses such as control room, office and base camp in plant facilities. Ambient noise source should be checked in initial design stage to minimize the speech interference.

Noise Study

Noise study includes getting the noise contour map& survey data in plant facilities, and defines the noise restricted area with control design, if necessary.

Industrial Noise

Industrial noise assessment has considered the noise impact by plant facilities such as gas, petroleum, chemical, power plant, in which many kinds of noise sources have been applied. INERTANCE has predicted the noise levels by rotating equipment, piping system, valves based on our experience in the specialized field, and the same has been considered to the equipment arrangement via noise allocation study during initial design stage.

INERTANCE has a capability to perform below kinds of noise study.

• Case Study for Emergency Condition
• Worker Hearing Loss
• Hearing Conservation Program
• Work Area Noise Level
• Definition for Noise Restricted Area
• Absolute Noise Limit
• Local Regulation of Noise 
• Industrial Noise for Plant 
• Ambient Noise Survey 
• Noise Verification Survey during Commissioning Stage

Construction Noise

Construction noise is a significant problem in compact big city, and it is normally controlled by local regulations. The noise assessment based on survey is conducted to adjust the construction activities so that the noise severity can be mitigated.

Railway Noise

Railway noise is a major noise source normally in a big city, generated by moving and long line vehicles such as train or subway.

Road Traffic Noise

Road traffic noise is the most important source of environmental noise, and INERTANCE has investigated the noise pollution caused by transportation such as vehicle, truck during day & night time in order obtain the result which can be used to verify the noise prediction shown in a contour map.

Noise Assessment

INERTANCE provides the powerful noise contour map using relevant simulation tools, which is generated by various noise sources such as transportation, industrial and recreational activities around residential area. Noise assessment has to be carried out to estimate the noise pollution to check the compliance with local noise limitation.

Environmental Noise

INERTANCE has performed the environmental noise assessment to be line with applicable local environmental noise limits against transportation and industrial noise around residential area.

Site & Road investigations are carried out to predict the estimated noise level during day & night time, which can be shown as noise contour map respectively, and it is determined if the noise contour measure as anti-noise facilities (ex. Barrier) should be designed.

Noise contour map is used to understand the noise status propagated around interested area, which is often verified via noise verification survey. INERTANCE has a capability to perform below kinds of noise study.

• Noise Pollution
• Local Regulation of Noise
• Health Effects from Noise
• Noise Contour Map
• Noise Exposure
• Noise Source such as Vehicles, Aircraft, Trains and Industrial Sources
• Sound Pressure Level (SPL) and Sound Power Level (PWL)
• Definition for Residential Area
• Noise Induced Hearing Loss
• Definition for Maximum Allowable Noise Level
• Background Noise
• Propagation of Sound
• Noise Analysis
• Environmental Noise Control