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The purpose of this study is to numerically simulate the Lamb wave propagation through a clamp-on ultrasonic gas flowmeter (UGF) in contact mode, using a new semi three-dimensional approach. Moreover, experimental and analytical modeling results for transit time difference method have been used to confirm the simulation results at different gas flow velocities from 0.3 to 2.4 m/s.

The new semi three-dimensional approach involves the simulation of the flow field of the gas in a three-dimensional model and subsequently the simulation of wave generation, propagation and reception in a two-dimensional (2D) model. Moreover, the analytical model assumes that the wave transitions occur in a 2D mode.

The new approach is a semi three-dimensional approach used in this work, has better accuracy than a complete 2D simulation while maintaining the computing time and costs approximately constant. It is faster and less expensive than a complete 3D simulation and more accurate than a complete 2D simulation. It was concluded that the new approach could be extended to simulate all types of ultrasonic gas and non-gas flowmeters, even under harsh conditions.

In this work, a new approach for the numerical simulation of all types of ultrasonic flowmeters is introduced. It was used for simulation of a Lamb wave ultrasonic flow meter in contact mode.

To examine the possibilities for dry calibration or in situ calibration for flowmeters in the field.

Reviews history and current situation with regard to in situ/dry calibration of flowmeters. Its acceptability for modern flowmeters is considered. Various options are considered to achieve dry calibration or in situ calibration. The possibility of action at a distance via the internet, for example, naturally follows from these developments.

The paper concludes that this development is likely to be of importance to manufacturers. It will need to be addressed by certification authorities.

The concepts will reduce the cost of calibration and the discussion should be of value to research workers, industry and government.

Equipment, Programmes, Techniques and Projects. STRESS CORROSION TESTING MACHINE Saml. Denison & Son Ltd., Moor Road, Leeds 10, are now manufacturing a new environmental testing system — the T66 stress corrosion machine based on an original design licensed from British Aircraft Corporation (Operating) Ltd. of London. This machine is a four channel, vertical machine capable of testing 12 specimens simultaneously under load up to 10 tons (20,000 lb.). The specimens may be round or flat, three per channel, all loaded through special stainless steel holders and shackles. These shackles take over the specimen load when a specimen breaks, so maintaining load on the other specimens in the channel. Load is applied hydraulically and indicated on two facia dials. The hydraulic pressure is derived from an air/hydropump actuated by pressurised nitrogen. During a test the load on the specimens remains constant to plus or minus 100 lb. The environmental chamber consists of a polythene sleeve held in position by rubber O‐rings clamping on to Perspex top and bottom flanges thus making an airtight enclosure; into this can be fed the corrosive atmosphere. A salt‐spray unit is fitted in the centre for supplying one or all chambers. When sulphur dioxide is used, the supply from a cylinder is mixed with clean air and fed in via a flowmeter at 0.01–3 per cent mix.

The purpose of this study is to deal largely with the influence of temperature variation on the measurement accuracy of transit-time ultrasonic flowmeter.

The causes of measurement error due to temperature are qualitatively and quantitatively analyzed, and a mathematical model is established. The experimental data are processed and analyzed, and the temperature compensation coefficient of flow measurement is obtained.

The experimental results show that the flow measurement results by temperature compensation are helpful in improving the measurement accuracy of the ultrasonic flowmeter.

This study has certain application value, which can provide theoretical support for the design of high-precision ultrasonic flowmeters and design guidance.

It is worth emphasizing that there are few research studies on the influence factors of temperature. This paper focuses on the influence of the temperature change on the flowmeter that is modeled, and the high precision flow parameter test system is designed based on the established model.

Controlling paint production. Paint users are placing higher demands on the manufacturer. All paint producers should now consider data acquisition — and possibly automated paint manufacturing if the volumes of certain products will justify it.

An engine test rig has been designed and built for evaluation of monolithic ceramic components and metal components protected by ceramic shields or coatings for operation in the high temperature environment of the combustion gases of an uncooled diesel engine. Tests on the first monolithic ceramic components have shown thermal shock capability to be more critical than resistance to tensile bending, or vibration induced stresses. Configuration design can reduce the effects of the latter more readily than it can deal with thermal shock.

Brief Details of Some of the Components and Equipment Produced by a Number of Companies in Support of the Super VC10 Programme. THE preceding articles have dealt with the raison d'être of the Super VC10, interior engineering, technical details of the combined passenger/freight version, principal differences between the Standard and Super VC10s, development of Economy class seating for B.O.A.C.'s VC10s and aircraft systems. It is the object of this final article to provide some additional information regarding Super VC10 equipment and systems in the form of the contribution made by specific firms to the Super VC10 programme.