2017. 9. 20.
Isolator Design
HVAC equipments including ducts & piping system as well as rotating equipments should be mounted on suitable anti-vibration isolator, and they can reduce the vibration transmitted level to critical area. INERTANCE can design most effective isolator according to relevant guidelines.
HVAC Vibration
The vibration is normally generated by HVAC equipment and fluid behavior inside of ducts and pipes, which is the major source of occupant complaints in modern buildings. Vibration can design the anti-vibration isolator in order to minimize the vibration transmissibility from HVAC system.
INERTANCE has a capability to perform below kinds of estimation for HVAC Vibration.
- Design for Vibration Isolator
- Design for Fan, Pump, Chiller, Cooling Tower, Duct, Pipe, etc
- Spring Mount, Rubber Mount and Pad
- Spring Constant and Deflection Estimation
- Inertial Base for HVAC Pump
- Selection Guide for Vibration Isolation as per ASHRAE Handbook
Noise Criteria Assessment
The background noise related HVAC has to be considered for sound quality as per each room types. INERTANCE considers many possible sound transmission paths between noise source and receivers, and has determined to conduct the noise criteria assessment with relevant control design.
Duct Silencer Sizing
Airborne noise is passed through duct line of air supply/return system, and the sizing of duct silencer is the most important factor to determine the grade of noise & room criteria. INERTANCE has considered the transmission paths of noise and specification of air handling units in order to calculate the noise level in each room, and the silencer dimension has been calculated with proper air velocity as per room types.
HVAC Noise
HVAC equipment is the major sources of noise in building, and its effects on the speech interference & noise environment in each room have to be considered properly. INERTANCE has estimated the noise effects from HVAC equipment and designed the relevant control devices as per noise & room criteria.
INERTANCE has a capability to perform below kinds of estimation for HVAC Noise.
- Sound Attenuator & Silencer Sizing
- Sound Chamber and Elbow
- Duct Lagging
- Acoustic Insulation for Plumbing Pipe
- Indoor Noise Assessment
- Noise Criteria (NC)
- Room Criteria (RC)
- Duct Break out Noise
- Duct Break in Noise
- Estimation for Insertion Loss
- Acoustically Lined Rectangular Duct
- Acoustically Lined Round Duct
- Sound Transmission Loss
Transient Analysis
The process events have to be defined as per operating condition with reviewing the relevant documents to perform the transient analysis. As per results of transient analysis, INERTANCE has checked whether the maximum allowable surge pressure is acceptable with design pressure and international standards.
Steady State Analysis
The pipeline is firstly modeled to analysis the steady state operating conditions for the purpose of the surge analysis. This initial study is useful to match the process condition with analysis boundary condition and input parameters.
Surge Analysis (Water Hammer)
The surge phenomenon like water hammer describes a transient condition in piping systems caused when changing pressure or flow boundary condition, or changing operating condition of equipment such as pump and valve, etc. The surge pressure by transient condition is much higher than steady state, in which we should check if the piping design pressure is acceptable as per maximum allowable surge pressure.
Surge Analysis
INERTANCE has performed the surge analysis for long pipeline as well as network system with various process upset conditions. This analysis study has used a computer based mathematical model of the system to calculate the surge pressure of transient events.
INERTANCE has a capability to perform below kinds of rotor dynamics analysis.
- Steady State Analysis
- Case Study for Transient Analysis
- Surge Pressure ASME B31.1 and ASME B31.3
- Water Hammer Analysis
- Liquid Filled Piping System
- Parallel Operation for Centrifugal Pump
- Rapid Closure of a Valve
- Emergency Shut Down by Power Failure, etc
- Surge Control Measures
- Air Chamber and Surge Tank
Flow Induced Vibration
In piping system, the turbulent energy is generated by fluid flow, hence, the process condition as well as pipe geometry has to be considered together for quantitative assessment of flow induced vibration. In most experience cases at practice, the dominant sources of flow induced turbulence are flow discontinuities in the piping system.
The dominant energy is concentrated at low frequency below 100 Hz with high level of excitation. INERTANCE has provided the engineering services to estimate the low frequency vibration modes of the piping system, and has designed the arrangement of piping support system.
High Frequency Acoustic Excitation
Acoustic spectrums of pressure let-down device generally have a broad band range with peak frequency in excess of 1000 Hz, which is radiated into the downstream piping. This kinds of high frequency acoustic excitation is the main reasons for acoustic fatigue failure, and the mitigation measures has to be considered to minimize the piping system stress.
Pipe Geometry
Pipe diameter and thickness has to be checked in order to screen the potential fatigue failure caused by acoustic induced vibration, as the fatigue failure is more prevalent with thin wall and large diameter pipe. The acoustic energy generated from pressure let-down device is propagated to downstream piping system, and the fitting type and branch size have to be evaluated on the piping discontinuities location.
Pressure Let Down System
Pressure reducing system such as control valve and pressure safety valve in piping system is subject to rapidly decreasing pressure by flow restriction, which create the high velocity fluid, turbulent mixing and may cause the acoustic energy. The sound power levels are calculated as per process condition, and it is key parameters in problem concerning acoustically induced vibration.
Acoustic Induced Vibration
INERTANCE has performed the acoustic induced vibration for piping system, and has provided the best solution to prevent the likelihood of fatigue failure caused by acoustic induced vibration.
INERTANCE has a capability to perform below kinds of acoustic induced vibration analysis.
- Acoustically induced vibration (AIV)
- Acoustic fatigue in pipes
- High frequency acoustic excitation source
- Sound power level (PWL)
- Small bore connection analysis
- Pressure let-down device (Control valve, pressure relief valve, pressure safety valve, orifice, etc)
- As per API 521, Concawe report no, 85/82
- Pipe geometry parameter
- Pipe energy parameter (Mach number)
- Noise calculation as per IEC
- Likelihood of failure assessment
- Acoustic induced vibration control measures
- Fitting type: Weldolet, sweepolet, equal tee, reduced tee, nipolet, latrolet, etc
- Gusset support, reinforced pad, etc
- Energy institute guideline
- Detail FEA assessment
Reciprocating Pump
The pulsation study for reciprocating pump could be performed as per API 674, and INERTANCE has a capability to perform below kinds of pulsation study.
- Pulsation Study as per API 674
- Pulsation Dampener and Surge Volume Sizing
- Acoustic Simulation
- Calculation of Peak-to-Peak Pulsation Levels
- Pulsation Induced Shaking Forces (Unbalanced Forces)
- Piping Modification
- Mechanical Review and Piping Restraint Analysis
- Mechanical Natural Frequency
- Separation Margin Requirements
- Pulsation Controls by Orifice
- Acceleration Head
- Net Positive Inlet Pressure (NPIP) and Net Positive Suction Head (NPSH)
- Volumetric Efficiency and Pulsation
- Helmholtz Frequency Estimation
Reciprocating Compressor
The pulsation study for reciprocating compressor could be performed as per API 618, and INERTANCE has a capability to perform below kinds of pulsation study.
- Pulsation Study as per API 618
- Design Approach Guidelines
- Pulsation Criteria for Piping System
- Pulsation Criteria for Compressor Cylinder Flange
- Pulsation Suppression Device
- Pulsation Bottle Sizing as per API 618 & API 11P
- Pulsation Induced Shaking Force (Unbalanced Forces)
- Acoustic Simulation
- Calculation of Peak-to-Peak Pulsation Levels
- Piping Vibration Criteria
- Piping Modification
- Mechanical Review and Piping Restraint Analysis
- Mechanical Natural Frequency
- Separation Margin Requirements
- Pulsation Controls by Orifice
- Acoustic Resonance
- Acceleration Head
- Surge Volume and Acoustic Filter
- Helmholtz Frequency Estimation
The objective to perform the pulsation study is to avoid problems with vibration, performance, reliability, and flow measuring error caused by acoustical interaction between the compressor and the relevant piping system.
Pulsation study procedure has been determined as per design approach guideline as per API 618.
Pulsation study procedure has been determined as per design approach guideline as per API 618.
1. Design Approach 1
Design Approach 1 is to perform the empirical pulsation suppression device design using proprietary and empirical analytical techniques to meet line side pulsation levels and the maximum pressure drop based on compressor normal operating condition.
2. Design Approach 2
Design Approach 2 is to perform the acoustic simulation and piping restraint analysis, which include the pulsation control through the use of pulsation suppression devices and proven acoustic techniques. In case the detail design of piping system is finalized, the acoustic simulation has to be performed for system reliability. Then, the separation margin based on mechnical natural frequency has to be checked to avoid the mechanical resonance.
3. Design Approach 3
Design Approach 3 is to perform the mechanical analysis with forced mechanical response analysis in addition to Design approach 2. The forced mechanical response analysis for compressor cylinder as well as associated piping systems has to be performed as results of previous analysis results.
Vibration Monitoring
INERTANCE provides the engineering services for field measurement for turbo-machinery to resolve the vibration issue as trouble shooting. As a result of vibration monitoring, the root cause analysis has been performed, and the relevant counter measures have been applied.
Application of necessary measurement devices are INERTANCE’s capability for vibration monitoring, which has been useful to find the root cause such as unbalance, alignment and looseness, etc.
INERTANCE has a capability to perform below kinds of vibration monitoring analysis.
- Vibration survey
- Root cause analysis
- Trouble shooting for vibration control
- Bearing analysis
- Data recording & reproduction
- Field balancing
- Vibration displacement, velocity, acceleration
- Unbalance, misalignment, looseness, resonance, oil whirl & whip, eccentricity, shaft bent,
- Synchronous, non-synchronous, sub-synchronous vibration
- Orbit, Trend, Bode plot, Polar diagram, Shaft center line, Spectrum analysis, Waterfall diagram, Full spectrum analysis,
- Phase analysis
- Modal analysis, Bump test, etc
Torsional Stress Analysis
If the undamped torsional analysis has a result of interference between excitation sources and natural frequency under operating region, the torsional stress analysis has to be carried out. INERTANCE provides the stress analysis such as Stress-life method, Strain-life method, Goodman diagram method, etc.
Steady State Damped Response Analysis
Torsional excitation sources have to be considered to perform the steady state damped response analysis. The magnitude of torque & torsional displacement is checked for reliabilities of each component such as coupling, etc.
피드 구독하기:
글 (Atom)