Insulation Cover Research Articles

Effect of baffle plate on the performance of built-in storage type solar water heater

The performance of a built-in storage water heater can be improved by using a baffle plate in the absorber tank. We have studied the following different design conditions: 1. (i) a water heater with baffle plate and with night insulation cover, 2. (ii) with baffle plate and without night insulation cover, 3. (iii) without baffle plate and with night insulation cover. We find that the best results are obtained with a baffle plate and an insulation cover at night. The performance of the system without the cover but with the baffle plate is almost as good as that with cover and without the baffle plate. We have also studied the design 1. (i) when water is withdrawn from the system at various constant flow rates.

Effect of the baffle plate on transient performance of built-in-storage water heater

This communication presents a study on the effects of variation in the inlet and outlet vent area of the baffle plate, variation in the thickness of upper and lower water columns and use of an insulation cover during the night on the transient variation of water temperature of a built-in-storage solar water heater. The effect of duration of water flow rate in the lower column on its performance has also been studied. Numerical calculations have been made for a typical day in Delhi for December 1979.

Theoretical and experimental studies on collector/storage type solar water heater

Extensive theoretical and experimental studies on a built-in-storage solar water heater which was developed earlier by Garg in India, are carried out. In this water heater the absorber plate performs the dual function of absorbing the solar energy and storing the heated water. In the theoretical study, the transient performance of the system is predicted by solving the mathematical models consisting of energy balance equations which are written on different collector nodes by considering their capacity effects and various heat loss effects. These equations are converted in the finite difference form and then solved by digital computer. Solar radiation and ambient temperature are represented by Fourier series in the theoretical analysis. Its night cooling drawback is somehow checked by covering the collector system by an insulation cover during cooling hours and also by using a insulated baffle plate inside the tank adjacent to the absorber plate. It is observed that by using the insulation cover, the collector performance can be improved by 70 per cent. Use of baffle plate improves the performance during day as well as night time.

The Application of Cable in Cathodic Protection

Abstract The requirements of a suitable metallic conductor in a cathodic protection system are discussed. Particular attention is paid to economic factors and power loss in the selection of suitable conductors and the most satisfactory cable sizes. Data are given to show the relative electrical resistivity of copper, aluminum, iron and lead. The selection of cable insulation and protective coverings in cathodic protection systems is discussed in detail. Data are given to show physical and accelerated aging requirements of polyethylene insulation and polyvinyl chloride sheath compound. Data also are included show the electrical stability of various types of insulation after immersion in tap water, and after immersion in various chemicals. Other topics discussed include mechanical properties of insulation, insulation versus environment, installation techniques and splicing requirements. It was found that a cable construction which makes use of a polyethylene insulation and a polyvinyl chloride sheathing com...