Turbomachinery with variable-angle fluid guiding vanes

A turbomachinery with a variable-angle flow guiding device comprising:

• an impeller;
• diffuser vanes;
• parameter monitoring means for monitoring inlet flow volume rates or an operational parameter of the turbomachinery or a drive source thereof, said operational parameter being correlative to the inlet flow volume rates;
• and
• a control means for controlling a setting angle of diffuser vanes in accordance with a sum of a first angle and a second angle,
• wherein said first angle is a fluid flow angle obtained from a relation between flow angles at an exit of said impeller and inlet flow volume rates, and said second angle is an angle equivalent to an angle of attack,
• wherein said relation is given by an equation:
• .alpha.=arc tan {Q/(K.sub.1 N-K.sub.2 Q)}
• wherein .alpha. is the flow angle, Q is the inlet flow volume rate, K.sub.1 is a constant given by (.pi.D.sub.2).sup.2 .sigma.b.sub.2 B, K.sub.2 is a constant given by cot.beta..sub.2, .sigma. is a slip factor, B is a blockage factor, N is the rotational speed, .beta..sub.2 is the blade exit angle of the impeller in the tangential direction, and D.sub.2 is the impeller outer diameter.

A turbomachinery with a variable-angle flow guiding device comprising:

• an impeller;
• diffuser vanes;
• parameter monitoring means for monitoring inlet flow volume rates or an operational parameter of the turbomachinery or a drive source thereof, said operational parameter being correlative to the inlet flow volume rates;
• a rotation speed sensor for detecting rotation speed of said turbomachinery;
• and
• a control means for controlling a setting angle of diffuser vanes in accordance with a sum of a first angle and a second angle wherein said first angle is a fluid flow angle obtained from a predetermined relation between flow angles at an exit of said impeller and inlet flow volume rates, and said second angle is an angle equivalent to an angle of attack,
• wherein said predetermined relation is given by an equation:
• .alpha.=arc tan {Q/(K.sub.1 N-K.sub.2 Q)}
• wherein .alpha. is the flow angle, Q is the inlet flow volume rate, K.sub.1 is a constant given by (.pi.D.sub.2).sup.2 .sigma.b.sub.2 B, K.sub.2 is a constant given by cot.beta..sub.2, .sigma. is a slip factor, B is a blockage factor, N is the rotational speed, .beta..sub.2 is the blade exit angle of the impeller in the tangential direction, and D.sub.2 is the impeller outer diameter.

A turbomachinery with a variable-angle flow guiding device comprising:

• an impeller;
• diffuser vanes;
• parameter monitoring means for monitoring inlet flow volume rates or an operational parameter of the turbomachinery or a drive source thereof, said operational parameter being correlative to the inlet flow volume rates;
• pressure monitoring means for monitoring inlet and exit pressures;
• and
• a control means for controlling a setting angle of diffuser vanes in accordance with a sum of a first angle and a second angle wherein said first angle is a fluid flow angle obtained from a predetermined relation between flow angles at an exit of said impeller and inlet flow volume rates, and said second angle is an angle equivalent to an angle of attack, wherein said first angle is computed from an equation:
• .alpha.=arc tan ›(1/P.sub.r).sup.1/.kappa. .multidot.Q/{K.sub.1 N-(1/P.sub.r).sup.1/.kappa. .multidot.K.sub.2 Q}!
• wherein .alpha. is a flow angle, Q is an inlet flow volume rate, P.sub.r is a ratio of pressures at inlet and exit, K.sub.1 is a constant given by (.pi.D.sub.2).sup.2 .sigma.b.sub.2 B, K.sub.2 is a constant given by cot.beta..sub.2, .sigma. is a slip factor, .kappa. is a ratio of specific heats, B is a blockage factor, N is a rotational speed, .beta..sub.2 is a tangential flow angle from the impeller, and D.sub.2 is an impeller outer diameter.

A turbomachinery with a variable-angle flow guiding device comprising:

• an impeller;
• diffuser vanes;
• parameter monitoring means for monitoring inlet flow volume rates or an operational parameter of the turbomachinery or a drive source thereof, said operational parameter being correlative to the inlet flow volume rates;
• a rotation speed sensor for detecting rotation speed of said turbomachinery;
• pressure monitoring means for monitoring inlet and exit pressures;
• and
• a control means for controlling a setting angle of diffuser vanes in accordance with a sum of a first angle and a second angle wherein said first angle is a fluid flow angle obtained from a predetermined relation between flow angles at an exit of said impeller and inlet flow volume rates, and said second angle is an angle equivalent to an angle of attack, wherein said first angle is computed from an equation:
• .alpha.=arc tan ›(1/P.sub.r).sup.1/.kappa. .multidot.Q/{K.sub.1 N-(1/P.sub.r).sup.1/.kappa. .multidot.K.sub.2 Q}!
• wherein .alpha. is a flow angle, Q is an inlet flow volume rate, P.sub.r is a ratio of pressures at inlet and exit, K.sub.1 is a constant given by (.pi.D.sub.2).sup.2 .sigma.b.sub.2 B, K.sub.2 is a constant given by cot.beta..sub.2, .sigma. is a slip factor, .kappa. is a ratio of specific heats, B is a blockage factor, N is a rotational speed, .beta..sub.2 is a tangential flow angle from the impeller, and D.sub.2 is an impeller outer diameter.

A method of controlling an operation of a turbomachinery having inlet guide vanes and impellers comprising the steps of:

• obtaining current operating data through sensors arranged within said turbomachinery;
• computing a parameter representing a degree of stability of the flow within said impeller based on said current operating data;
• and
• adjusting the angle of said inlet guide vane and rotational speed of said impeller so that said parameter is maintained within a predetermined range and the flow rate value and the head value measured by said sensors satisfy respective required values,
• wherein said operating parameter is a ratio of fluid velocity at the inlet and exit of said impeller.

A method of controlling an operation of a turbomachinery having inlet guide vanes and impellers comprising the steps of:

• obtaining current operating data through sensors arranged within said turbomachinery;
• computing a parameter representing a degree of stability of the flow within said impeller based on said current operating data;
• and
• adjusting the angle of said inlet guide vane and rotational speed of said impeller so that said parameter is maintained within a predetermined range and the flow rate value and the head value measured by said sensors satisfy respective required values,
• wherein said operating parameter is a rate of change of a ratio of fluid pressure at the inlet and exit of said impeller with respect to a flow rate.