Southwest Research Institute

Gas Research Institute

Gas Machinery Research Council

Ralph E Harris

Gary D Bourn

Anthony J Smalley

Eugene L Broerman, Iii

Dean C Winter

Kevin S Honeyager

Carl E Edlund

James J Cole

C Richard Gerlach

Jack A Smith

Christine M Scrivner

Kurt A Franke

A method and system for reducing pulsation in lateral piping associated with a gas compressor system. A tunable side branch absorber (TSBA) is installed on the lateral piping. A pulsation sensor is placed in the lateral piping, to measure pulsation within the piping. The sensor output signals are delivered to a controller, which controls actuators that change the acoustic dimensions of the SBA.

Gas compressor with side branch absorber for pulsation control

A method of improving scavenging operation of a two-stroke internal combustion engine. The exhaust pressure of the engine is analyzed to determine if there is a pulsation frequency. Acoustic modeling is used to design an absorber. An appropriately designed side branch absorber may be attached to the exhaust manifold.

Side branch absorber for exhaust manifold of two-stroke internal combustion engine

A method and system for controlling an engine that drives a reciprocating compressor, such as the large compressors used for natural gas transmission. A controller receives data from the compressor representing operation conditions, such as load step, suction pressure, and discharge pressure. The controller then calculates engine control parameters, such as air intake and spark timing, based on the compressor data to optimize engine performance and emissions.

Integrated engine/compressor control for gas transmission compressors

An apparatus and method for monitoring a reciprocating member of a reciprocating piston compressor is presented. The apparatus and method provide a means for measuring parameters of the reciprocating member, such as road load or cross-head temperature and the like, and wirelessly transmitting the data to a receiver. A mobile assembly is attached to a reciprocating member of the compressor, the mobile assembly having a sensor assembly, a wireless transmitter and a power generation assembly. The sensor assembly measures a parameter of the reciprocating member and generates a representative sensor signal. The wireless transmitter wirelessly transmits a corresponding data signal to a stationary assembly mounted nearby. The power assembly powers the transmitter and sensor assembly. The measured data is used, in conjunction with other measurements, such as a crankshaft encoder, to calculate the work performed by the compressor, the power used by the compressor and other information. The compressor utilization is then optimized based on the gathered information.

Method and apparatus for measuring work performed by a compressor

A method of balancing combustion among cylinders of an internal combustion engine. For each cylinder, a normalized peak firing pressure is calculated as the ratio of its peak firing pressure to its combustion pressure. Each cylinder's normalized peak firing pressure is compared to a target value for normalized peak firing pressure. The fuel flow is adjusted to any cylinder whose normalized peak firing pressure is not substantially equal to the target value.

Internal combustion engine cylinder-to-cylinder balancing with balanced air-fuel ratios

A high frequency oscillatory ventilator for infants and adults using feedback control to maintain either the desired tidal volume or pressure delivered to the subject. The inspiratory to expiratory time ratio of the ventilator is variable. The ventilator corrects the measured pressure for arbitrarily-sized endotracheal tubes and calculates the actual pressure or tidal volume delivered to the subject. The ventilator also separates the source of the tidal volume oscillations from the patient circuit with a flexible membrane or diaphragm, allowing transmission of oscillating tidal volumes while blocking mean airway pressures. The patient circuit is flexible, but fabricated from low-compliance material to minimize the loss of tidal volume. The ventilator uses feedback control of the exhaust flow to maintain mean airway pressure in the presence of an independently controlled bias flow. Further, a respiratory impedance measurement system is built into or connected to the patient circuit which monitors changes in lung mechanics while the patient is connected to the high frequency ventilator without changing mean airway pressure or removing the patient from the ventilator.

High frequency oscillatory ventilator and respiratory measurement system

A computer-based system and method detects and specifies valve and ring leaks in reciprocating compressors of the type used in natural gas transmission networks. The system employs a method comprising the following steps. The cylinder pressure is measured as a function of cylinder volume to obtain a measured PV card. A predictive model then calculates a predicted PV card for the subject compressor cylinder without including effects of simulated leaks. The predicted PV card is them compared to the measured PV card. The nature and character of the differences between the measured and predicted PV cards indicates whether a leak in the subject compressor cylinder is a suction valve leak, a discharge valve leak, or a piston ring leak. The predictive model is then iterated with simulations of the indicated leak included until the resulting predicted PV card matches the actual measured PV card for the compressor cylinder. The final value of the leak parameters in the model required for the match indicate the nature and magnitude of a corresponding actual leak in the compressor cylinder. Other useful information such as the efficiency of the compressor system with and without the leak and the economic impact of the leak are also derived from the iterative match process.

Growing community of inventors

San Antonio, TX, United States of America

Ralph E Harris