"PREFACE TO HEAT TRANSFER SERIES Engineers concerned with heat transfer equipment face an ever-increasing demand for products with a performance that must be substantiated under stringent constraints of cost and operation. Customers for their products are skilled in the ways of achieving@ and are fully aware of what can be achieved by@ competitively designed equipment. Assuming the basic skill of the designer@ no other single factor can contribute more to the economic preparation of a satisfactory@ competitive design than the data upon which that design is based and the speed with which those data can be found and applied. Heat transfer data@ in common with those relating to many other disciplines of concern to the engineer@ are widely scattered and when found are of variable quality and relevance to the industrial application. Engineers do not@ generally speaking@ have the facilities to collect and evaluate all the data available which may be applicable to each aspect of their work. Even if they had the desire to undertake such a task it is unlikely that they could allow the time necessary to prepare their own data ""working tools"" at the expense of time spent in the application of knowledge and experience to the particular job in hand. In any case@ equipment users will increasingly wish to view the design@ not against some locally-derived data but against what can be demonstrated to be the best available data whose integrity is underwritten by a significant cross-section of the engineering community concerned with the derivation and application of that data. It is ESDU's purpose to provide such data in many fields. ESDU has prepared this information for both the designer and equipment user and@ by serving the needs of many@ accomplishes the task at much lower cost than could apply to individuals performing it on their own behalf."