Vortex Cross-correlation Flowmeter

Indian Patent No - 1763/MUM/2013 (Granted)

Background: Vortex flowmeters are extensively used in various industrial applications for fluid flow measurement. The performance of vortex flowmeters is significantly compromised by various factors inherent to industrial processes, such as flow pulsations, piping vibrations, and installation effects. These factors attract significant concern, particularly when operating under low Reynolds number flow conditions, where the vortex signal is relatively weak. Consequently, these effects impose limitations on the flowmeter's lower operating range.

Novelty and Claim: A novel dual sensor vortex cross-correlation technique is suggested and implemented to extend the lower operating range of the flowmeter. This novel dual flow rate estimation technique has demonstrated its robustness under low Reynolds number flow conditions with a remarkable turndown ratio of 1:66 as compared to 1:20 for conventional vortex flowmeters.

Vortex Flowmeter for Measuring a fluid flow rate

Indian Patent No - 2459/MUM/2015 (Granted)

Background: Vortex flowmeters are widely employed in industrial applications to measure fluid flow. However, their performance is greatly affected by factors like flow pulsations, piping vibrations, and installation effects. Hence upstream and downstream straight pipes are required to achieve the required accuracy. However, this piping requirement is expensive and may not be feasible in industrial applications.

Novelty and Claim: A novel contraction cone design is proposed and implemented, which makes the flowmeter insensitive to any upstream disturbances and hence doesn’t require any straight piping upstream and downstream of the flowmeter.

A System And A Method To Create And Modulate Coaxial Synthetic Jets

Indian Patent No - 202131047214

Background: Many engineering applications like, aerodynamics, electronics cooling, and process industries and combustion requires effective utilization of fluids. Such applications demand an active flow control technique to manipulate the flow field to achieve the desired effects like turbulence enhancement and vortices. Existing flow control devices have limited scope due to their ineffectiveness in manipulating the flow field to achieve these desired effects.

Novelty and Claim: We proposed and demonstrated a Coaxial Synthetic Jet (CSJ) system for flow control application. By employing two piezo-electric diaphragms arranged coaxially with a 0° orientation angle, the system generates and controls flow jets to achieve the desired effect. These diaphragms can be independently operated at different amplitudes and frequencies without affecting the flow in either cavity. Moreover, the CSJ allows for adjusting phase differences between the diaphragms, ranging from 0° to 180°, providing versatile modulation capabilities. The compact design of the CSJ enables easy integration into electronic components, aerodynamics flow control, mixing, and combustion applications. With its ability to achieve different mass flux ratios, the CSJ represents a significant advancement in flow control technology.

A system and method for focusing of jets

Indian Patent No - TEMP/E-1/38398/2023-KOL

Novelty and Claim: The present invention introduces an innovative focusing technique to enhance the strength of synthetic jets (SJs) in the far-field. SJs often suffer from reduced vortex coherence, limiting their wide applicability. This issue also affects synthetic jet arrays (SJ arrays) composed of multiple adjacent actuators, where destructive interactions between opposite rotating vortices decrease coherence in the far field. The inventors propose focusing as a method to mitigate these destructive interactions in the near field, allowing vortices to evolve effectively, which results in achieving 50% enhancement in jet strength in the far field. Subsequently, constructive merging between vortices amplifies the jet strength in the far field. This novel focusing of SJs holds tremendous potential for enhancing electronic cooling, aerodynamics, and other applications.

A System and a Method for Multipoint Sensing

Indian Patent No - TEMP E-1/59888/2020/KOL

Background: Detection of vibration at multiple locations has applications in industrial operations, tracking of physiological motions for health monitoring and environmental surveillance. OTDR, FBG and classical interferometry techniques have been proposed in this regard. However, the OTDR and classical interferometric techniques are limited by reduced sensitivity with length of fiber while FBGs are temperature intolerant and lack scalability. Hence, more effective and reliable sensing and detection techniques are required.

Novelty and Claim: In this invention we propose an optical multipoint sensing system made of in-line modal interferometers concatenated along a single fiber channel. Each modal interferometer acts as sensor probe to independently respond to external perturbation and produce a resultant signal comprising the frequency components of the perturbing fields. Real time detection of amplitude, frequency and instantaneous phase of mechanical vibrations/disturbance at different locations is feasible. Signal comparison analysis achieves localization of signal components about each probe.

A Model Interferometer Based System to Improve Performance of Vortex Flow meter

Indian Patent No - E-5/320/2019/KOL

Background: Optical fiber-based vibration sensors are a potential class of technology. Their market value is rapidly increasing due to their high sensitivity and the potential to design versatile probes to detect various parameters. In practical applications, the performance of such sensor probes is affected by the external field noise and low amplitude of the external field. In order to improve their real time performance in complex environments, the modulation or conditioning of their responses is a definite solution. In this regard, methods based on spatial signal processing or phase noise cancellation have been reported. However, amplification, attenuation of noise components and filtering using a single system remained elusive.

Novelty and Claim: In the proposed invention, identical fiber modal interferometers are fabricated and combined parallelly, such that one arm acts as the sensing arm while the other acts as the reference arm. The sensing arm is exposed to an external measurand field while an equivalent field about the reference arm is applied in a controlled manner to modulate the resultant signal and achieve signal amplification, attenuation of unwanted frequencies, and enhance the signal-to-noise ratio of the output waveform. Real-time amplification, attenuation, and filtering of the dynamic optical response of sensor probes over a broad frequency range is feasible. The proposed system can be applied for conditioning the response of an optical fiber sensor deployed to detect external physical fields.

A Rational System for Testing Resilient Modulus of Unbound Granular Materials

Indian Patent No - Patent Application Submitted

Background: Resilient Modulus (MR) of Unbound Granular Materials (UGMs) is a critical parameter in the Mechanistic-Empirical (M-E) pavement design procedure. In most countries empirical correlations are used to determine MR of unbound granular layers due to the complex, time- consuming and resource-intensive nature of Repeated Load Triaxial Tests (RLTT). Alternative set-ups such as Springbox, K-Mould and PUMA are available for determination of MR. But the confining pressure is not entirely user regulated in these set-ups as it is applied via spring or rubber. And none of the mentioned test set-ups consider the effect of subgrade stiffness on the MR of UGMs

Novelty and Claim: A simple and rational test set up has been developed for the determination of Resilient Modulus of Unbound Granular Materials (UGMs) that can simulate the elastic subgrade support during the test. Resilient Modulus Test of UGMs can be conducted without containing the specimen in rubber membranes at user regulated confining pressure. A single acting pneumatic cylinder provided at the bottom simulates the stiffness of the soil subgrade and can be varied depending on the type of soil. Specimen can be compacted and contained inside a split mould and confining stress can be applied through four pneumatic cylinders.